Version 2.8.6

* Fix doc comment errors in ObjC APIs
* Improve doc comments in LayoutAnchoring.swift

.circleci/config.yml

@@ -7,15 +7,8 @@ jobs:
     steps:
       - checkout
       - run: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=14.5,name=iPhone 12 Pro'
-  test-ios13_7-iPhone_11_Pro:
-    macos:
-      xcode: 12.5.1
-    steps:
-      - checkout
-      - run: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=13.7,name=iPhone 11 Pro'
 
 workflows:
   test: 
     jobs:
       - test-ios14_5-iPhone_12_Pro
-      - test-ios13_7-iPhone_11_Pro

.github/workflows/ci.yml

@@ -11,65 +11,74 @@ on:
 
 jobs:
   build:
-    runs-on: ${{ matrix.runsOn }}
+    runs-on: ${{ matrix.runs-on }}
     env:
       DEVELOPER_DIR: /Applications/Xcode_${{ matrix.xcode }}.app/Contents/Developer
     strategy:
       fail-fast: false
       matrix:
         include:
+          - swift: "5.10"
+            xcode: "15.4"
+            runs-on: macos-14
+          - swift: "5.9"
+            xcode: "15.2"
+            runs-on: macos-13
           - swift: "5.8"
-            xcode: "14.3"
-            runsOn: macos-13
+            xcode: "14.3.1"
+            runs-on: macos-13
           - swift: "5.7"
             xcode: "14.1"
-            runsOn: macos-12
+            runs-on: macos-12
           - swift: "5.6"
             xcode: "13.4.1"
-            runsOn: macos-12
+            runs-on: macos-12
           - swift: "5.5"
             xcode: "13.2.1"
-            runsOn: macos-11
-          - swift: "5.4"
-            xcode: "12.5.1"
-            runsOn: macos-11
-          - swift: "5.3"
-            xcode: "12.4"
-            runsOn: macos-11
-          - swift: "5.2"
-            xcode: "11.7"
-            runsOn: macos-11
+            runs-on: macos-12
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Building in Swift ${{ matrix.swift }}
         run: xcodebuild -scheme FloatingPanel SWIFT_VERSION=${{ matrix.swift }} clean build
 
   test:
-    runs-on: ${{ matrix.runsOn }}
+    runs-on: ${{ matrix.runs-on }}
     env:
       DEVELOPER_DIR: /Applications/Xcode_${{ matrix.xcode }}.app/Contents/Developer
     strategy:
       fail-fast: false
       matrix:
         include:
+          - os: "17.5"
+            xcode: "15.4"
+            sim: "iPhone 15 Pro"
+            parallel: NO  # Stop random test job failures
+            runs-on: macos-14
           - os: "16.4"
             xcode: "14.3.1"
             sim: "iPhone 14 Pro"
-            runsOn: macos-13
+            parallel: NO  # Stop random test job failures
+            runs-on: macos-13
           - os: "15.5"
             xcode: "13.4.1"
             sim: "iPhone 13 Pro"
-            runsOn: macos-12
+            parallel: NO  # Stop random test job failures
+            runs-on: macos-12
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Testing in iOS ${{ matrix.os }}
-      run: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=${{ matrix.os }},name=${{ matrix.sim }}'
+      run: |
+        xcodebuild clean test \
+          -workspace FloatingPanel.xcworkspace \
+          -scheme FloatingPanel \
+          -destination 'platform=iOS Simulator,OS=${{ matrix.os }},name=${{ matrix.sim }}' \
+          -parallel-testing-enabled '${{ matrix.parallel }}'
     timeout-minutes: 20
 
   example:
-    runs-on: macos-12
+    runs-on: macos-14
     env:
-      DEVELOPER_DIR: /Applications/Xcode_14.1.app/Contents/Developer
+      DEVELOPER_DIR: /Applications/Xcode_15.4.app/Contents/Developer
     strategy:
       fail-fast: false
       matrix:
@@ -79,40 +88,76 @@ jobs:
           - example: "Stocks"
           - example: "Samples"
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Building ${{ matrix.example }}
-      run: xcodebuild -workspace FloatingPanel.xcworkspace -scheme ${{ matrix.example }} -sdk iphonesimulator clean build
+      run: |
+        xcodebuild clean build \
+          -workspace FloatingPanel.xcworkspace \
+          -scheme ${{ matrix.example }} \
+          -sdk iphonesimulator
 
   swiftpm:
-    runs-on: macos-12
+    runs-on: macos-14
     env:
-      DEVELOPER_DIR: /Applications/Xcode_14.1.app/Contents/Developer
+      DEVELOPER_DIR: /Applications/Xcode_15.4.app/Contents/Developer
+    strategy:
+      fail-fast: false
+      matrix:
+        platform: [iphoneos, iphonesimulator]
+        arch: [x86_64, arm64]
+        exclude:
+          - platform: iphoneos
+            arch: x86_64
+        include:
+          # 17.2
+          - platform: iphoneos
+            sys: "ios17.2"
+          - platform: iphonesimulator
+            sys: "ios17.2-simulator"
+    steps:
+    - uses: actions/checkout@v4
+    - name: "Swift Package Manager build"
+      run: |
+        xcrun swift build \
+          --sdk "$(xcrun --sdk ${{ matrix.platform }} --show-sdk-path)" \
+          -Xswiftc "-target" -Xswiftc "${{ matrix.arch }}-apple-${{ matrix.sys }}"
+
+  swiftpm_old:
+    runs-on: ${{ matrix.runs-on }}
+    env:
+      DEVELOPER_DIR: /Applications/Xcode_${{ matrix.xcode }}.app/Contents/Developer
     strategy:
       fail-fast: false
       matrix:
         include:
+          # 16.4
+          - target: "x86_64-apple-ios16.4-simulator"
+            xcode: "14.3.1"
+            runs-on: macos-13
+          - target: "arm64-apple-ios16.4-simulator"
+            xcode: "14.3.1"
+            runs-on: macos-13
           # 15.7
           - target: "x86_64-apple-ios15.7-simulator"
+            xcode: "14.1"
+            runs-on: macos-12
           - target: "arm64-apple-ios15.7-simulator"
-          # 16.1
-          - target: "x86_64-apple-ios16.1-simulator"
-          - target: "arm64-apple-ios16.1-simulator"
+            xcode: "14.1"
+            runs-on: macos-12
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: "Swift Package Manager build"
-      run: swift build -Xswiftc "-sdk" -Xswiftc "`xcrun --sdk iphonesimulator --show-sdk-path`" -Xswiftc "-target" -Xswiftc "${{ matrix.target }}"
-
-  carthage:
-    runs-on: macos-11
-    steps:
-    - uses: actions/checkout@v3
-    - name: "Carthage build"
-      run: carthage build --use-xcframeworks --no-skip-current
+      run: |
+        swift build \
+          -Xswiftc "-sdk" -Xswiftc "`xcrun --sdk iphonesimulator --show-sdk-path`" \
+          -Xswiftc "-target" -Xswiftc "${{ matrix.target }}"
 
   cocoapods:
-    runs-on: macos-12
+    runs-on: macos-14
+    env:
+      DEVELOPER_DIR: /Applications/Xcode_15.4.app/Contents/Developer
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: "CocoaPods: pod lib lint"
       run: pod lib lint --allow-warnings
     - name: "CocoaPods: pod spec lint"

Examples/Maps/Maps/Base.lproj/Main.storyboard

@@ -1,7 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="19455" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="21701" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
+    <device id="retina6_12" orientation="portrait" appearance="light"/>
     <dependencies>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="19454"/>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="21679"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
@@ -11,16 +13,16 @@
             <objects>
                 <viewController id="BYZ-38-t0r" customClass="MainViewController" customModule="Maps" customModuleProvider="target" sceneMemberID="viewController">
                     <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
-                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                         <subviews>
                             <mapView clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="scaleToFill" mapType="standard" translatesAutoresizingMaskIntoConstraints="NO" id="5Jw-n2-Cpw">
-                                <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                                <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                             </mapView>
                             <visualEffectView opaque="NO" contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" id="d9i-3g-8Ja">
-                                <rect key="frame" x="0.0" y="0.0" width="600" height="0.0"/>
+                                <rect key="frame" x="0.0" y="0.0" width="393" height="59"/>
                                 <view key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" insetsLayoutMarginsFromSafeArea="NO" id="lMa-xa-AVV">
-                                    <rect key="frame" x="0.0" y="0.0" width="600" height="0.0"/>
+                                    <rect key="frame" x="0.0" y="0.0" width="393" height="59"/>
                                     <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                                 </view>
                                 <blurEffect style="prominent"/>
@@ -52,31 +54,31 @@
             <objects>
                 <viewController storyboardIdentifier="SearchViewController" useStoryboardIdentifierAsRestorationIdentifier="YES" id="0S1-Lk-JgE" customClass="SearchViewController" customModule="Maps" customModuleProvider="target" sceneMemberID="viewController">
                     <view key="view" contentMode="scaleToFill" id="Ncl-E9-yRn">
-                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                         <subviews>
                             <visualEffectView opaque="NO" contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" id="Ye3-uU-bq3">
-                                <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                                <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                                 <view key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" insetsLayoutMarginsFromSafeArea="NO" id="ED1-gT-FBj">
-                                    <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                                    <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                                     <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                                     <subviews>
                                         <searchBar contentMode="redraw" searchBarStyle="minimal" translatesAutoresizingMaskIntoConstraints="NO" id="Zcj-SE-gb8">
-                                            <rect key="frame" x="0.0" y="6" width="600" height="51"/>
+                                            <rect key="frame" x="0.0" y="6" width="393" height="56"/>
                                             <textInputTraits key="textInputTraits"/>
                                         </searchBar>
-                                        <tableView clipsSubviews="YES" contentMode="scaleToFill" alwaysBounceVertical="YES" showsHorizontalScrollIndicator="NO" showsVerticalScrollIndicator="NO" dataMode="prototypes" style="plain" separatorStyle="default" rowHeight="-1" estimatedRowHeight="-1" sectionHeaderHeight="28" sectionFooterHeight="28" translatesAutoresizingMaskIntoConstraints="NO" id="D7r-re-InH">
-                                            <rect key="frame" x="0.0" y="61" width="600" height="539"/>
+                                        <tableView clipsSubviews="YES" contentMode="scaleToFill" alwaysBounceVertical="YES" showsHorizontalScrollIndicator="NO" dataMode="prototypes" style="plain" separatorStyle="default" rowHeight="-1" estimatedRowHeight="-1" sectionHeaderHeight="28" sectionFooterHeight="28" translatesAutoresizingMaskIntoConstraints="NO" id="D7r-re-InH">
+                                            <rect key="frame" x="0.0" y="66" width="393" height="786"/>
                                             <color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                                             <view key="tableHeaderView" contentMode="scaleToFill" id="u28-LY-hIh" customClass="SearchHeaderView" customModule="Maps" customModuleProvider="target">
-                                                <rect key="frame" x="0.0" y="0.0" width="600" height="116"/>
+                                                <rect key="frame" x="0.0" y="0.0" width="393" height="116"/>
                                                 <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
                                                 <subviews>
                                                     <stackView opaque="NO" contentMode="scaleToFill" distribution="equalSpacing" baselineRelativeArrangement="YES" translatesAutoresizingMaskIntoConstraints="NO" id="era-8w-yA1">
-                                                        <rect key="frame" x="24" y="10.5" width="552" height="97.5"/>
+                                                        <rect key="frame" x="24" y="10.666666666666664" width="345" height="97.333333333333343"/>
                                                         <subviews>
                                                             <stackView opaque="NO" contentMode="scaleToFill" axis="vertical" spacing="6" translatesAutoresizingMaskIntoConstraints="NO" id="auI-1v-Yfk">
-                                                                <rect key="frame" x="0.0" y="0.0" width="60" height="97.5"/>
+                                                                <rect key="frame" x="0.0" y="0.0" width="60" height="97.333333333333329"/>
                                                                 <subviews>
                                                                     <imageView userInteractionEnabled="NO" contentMode="scaleToFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="food" translatesAutoresizingMaskIntoConstraints="NO" id="ErN-bC-qTx">
                                                                         <rect key="frame" x="0.0" y="0.0" width="60" height="60"/>
@@ -86,7 +88,7 @@
                                                                         </constraints>
                                                                     </imageView>
                                                                     <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="Food &amp; Drinks" textAlignment="center" lineBreakMode="tailTruncation" numberOfLines="2" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="nx2-fW-xAm">
-                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.5"/>
+                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.333333333333329"/>
                                                                         <fontDescription key="fontDescription" type="system" pointSize="13"/>
                                                                         <nil key="textColor"/>
                                                                         <nil key="highlightedColor"/>
@@ -94,7 +96,7 @@
                                                                 </subviews>
                                                             </stackView>
                                                             <stackView opaque="NO" contentMode="scaleToFill" axis="vertical" spacing="6" translatesAutoresizingMaskIntoConstraints="NO" id="0vd-sD-XKv">
-                                                                <rect key="frame" x="164" y="0.0" width="60" height="97.5"/>
+                                                                <rect key="frame" x="95" y="0.0" width="60" height="97.333333333333329"/>
                                                                 <subviews>
                                                                     <imageView userInteractionEnabled="NO" contentMode="scaleToFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="shopping" translatesAutoresizingMaskIntoConstraints="NO" id="xcm-St-HAo">
                                                                         <rect key="frame" x="0.0" y="0.0" width="60" height="60"/>
@@ -104,7 +106,7 @@
                                                                         </constraints>
                                                                     </imageView>
                                                                     <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" verticalCompressionResistancePriority="1000" textAlignment="center" lineBreakMode="tailTruncation" numberOfLines="2" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="H7q-q2-ga5">
-                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.5"/>
+                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.333333333333329"/>
                                                                         <string key="text">Shopping
 </string>
                                                                         <fontDescription key="fontDescription" type="system" pointSize="13"/>
@@ -114,7 +116,7 @@
                                                                 </subviews>
                                                             </stackView>
                                                             <stackView opaque="NO" contentMode="scaleToFill" axis="vertical" spacing="6" translatesAutoresizingMaskIntoConstraints="NO" id="Jd8-YL-b5s">
-                                                                <rect key="frame" x="328" y="0.0" width="60" height="97.5"/>
+                                                                <rect key="frame" x="190" y="0.0" width="60" height="97.333333333333329"/>
                                                                 <subviews>
                                                                     <imageView userInteractionEnabled="NO" contentMode="scaleToFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="fun" translatesAutoresizingMaskIntoConstraints="NO" id="bMJ-Jn-Gi8">
                                                                         <rect key="frame" x="0.0" y="0.0" width="60" height="60"/>
@@ -124,7 +126,7 @@
                                                                         </constraints>
                                                                     </imageView>
                                                                     <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" textAlignment="center" lineBreakMode="tailTruncation" numberOfLines="2" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="kKh-45-FZ2">
-                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.5"/>
+                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.333333333333329"/>
                                                                         <string key="text">Fun
 </string>
                                                                         <fontDescription key="fontDescription" type="system" pointSize="13"/>
@@ -134,7 +136,7 @@
                                                                 </subviews>
                                                             </stackView>
                                                             <stackView opaque="NO" contentMode="scaleToFill" axis="vertical" spacing="6" translatesAutoresizingMaskIntoConstraints="NO" id="dTL-e1-Arz">
-                                                                <rect key="frame" x="492" y="0.0" width="60" height="97.5"/>
+                                                                <rect key="frame" x="285" y="0.0" width="60" height="97.333333333333329"/>
                                                                 <subviews>
                                                                     <imageView userInteractionEnabled="NO" contentMode="scaleToFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="travel" translatesAutoresizingMaskIntoConstraints="NO" id="8h3-fo-pC3">
                                                                         <rect key="frame" x="0.0" y="0.0" width="60" height="60"/>
@@ -144,7 +146,7 @@
                                                                         </constraints>
                                                                     </imageView>
                                                                     <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" textAlignment="center" lineBreakMode="tailTruncation" numberOfLines="2" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="WBT-Vj-7QA">
-                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.5"/>
+                                                                        <rect key="frame" x="0.0" y="66" width="60" height="31.333333333333329"/>
                                                                         <string key="text">Travel
 </string>
                                                                         <fontDescription key="fontDescription" type="system" pointSize="13"/>
@@ -166,10 +168,10 @@
                                             </view>
                                             <prototypes>
                                                 <tableViewCell clipsSubviews="YES" contentMode="scaleToFill" insetsLayoutMarginsFromSafeArea="NO" selectionStyle="blue" hidesAccessoryWhenEditing="NO" indentationLevel="1" indentationWidth="0.0" reuseIdentifier="Cell" rowHeight="70" id="LzC-B9-Adb" customClass="SearchCell" customModule="Maps" customModuleProvider="target">
-                                                    <rect key="frame" x="0.0" y="160.5" width="600" height="70"/>
+                                                    <rect key="frame" x="0.0" y="166" width="393" height="70"/>
                                                     <autoresizingMask key="autoresizingMask"/>
                                                     <tableViewCellContentView key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" insetsLayoutMarginsFromSafeArea="NO" tableViewCell="LzC-B9-Adb" id="evr-60-laS">
-                                                        <rect key="frame" x="0.0" y="0.0" width="600" height="70"/>
+                                                        <rect key="frame" x="0.0" y="0.0" width="393" height="70"/>
                                                         <autoresizingMask key="autoresizingMask"/>
                                                         <subviews>
                                                             <imageView userInteractionEnabled="NO" contentMode="scaleToFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="like" translatesAutoresizingMaskIntoConstraints="NO" id="GEk-yE-lLq">
@@ -181,16 +183,16 @@
                                                                 </constraints>
                                                             </imageView>
                                                             <stackView opaque="NO" contentMode="scaleToFill" axis="vertical" distribution="fillEqually" spacing="2" translatesAutoresizingMaskIntoConstraints="NO" id="Gfl-Oy-rsy">
-                                                                <rect key="frame" x="57" y="12" width="528" height="46"/>
+                                                                <rect key="frame" x="57" y="12" width="321" height="46"/>
                                                                 <subviews>
                                                                     <label opaque="NO" userInteractionEnabled="NO" tag="1" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="Favorites" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="Spf-8L-Ne6">
-                                                                        <rect key="frame" x="0.0" y="0.0" width="528" height="22"/>
+                                                                        <rect key="frame" x="0.0" y="0.0" width="321" height="22"/>
                                                                         <fontDescription key="fontDescription" type="boldSystem" pointSize="20"/>
                                                                         <nil key="textColor"/>
                                                                         <nil key="highlightedColor"/>
                                                                     </label>
                                                                     <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="0 Places" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="gyo-3V-7U8">
-                                                                        <rect key="frame" x="0.0" y="24" width="528" height="22"/>
+                                                                        <rect key="frame" x="0.0" y="24" width="321" height="22"/>
                                                                         <fontDescription key="fontDescription" type="system" pointSize="13"/>
                                                                         <color key="textColor" red="0.57647058819999997" green="0.57647058819999997" blue="0.57647058819999997" alpha="1" colorSpace="calibratedRGB"/>
                                                                         <nil key="highlightedColor"/>
@@ -255,18 +257,18 @@
             <objects>
                 <viewController storyboardIdentifier="DetailViewController" id="Tp2-MF-IFz" customClass="DetailViewController" customModule="Maps" customModuleProvider="target" sceneMemberID="viewController">
                     <view key="view" contentMode="scaleToFill" id="FmO-AT-4Y7">
-                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                         <subviews>
                             <visualEffectView opaque="NO" contentMode="scaleToFill" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="c3d-2e-0b1">
-                                <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                                <rect key="frame" x="-1" y="-1" width="393" height="852"/>
                                 <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                                 <view key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" insetsLayoutMarginsFromSafeArea="NO" id="9fL-a5-0LS">
-                                    <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                                    <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                                     <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                                     <subviews>
                                         <tableView clipsSubviews="YES" contentMode="scaleToFill" alwaysBounceVertical="YES" showsHorizontalScrollIndicator="NO" showsVerticalScrollIndicator="NO" dataMode="prototypes" style="plain" separatorStyle="default" rowHeight="-1" estimatedRowHeight="-1" sectionHeaderHeight="28" sectionFooterHeight="28" translatesAutoresizingMaskIntoConstraints="NO" id="kP7-56-wlG">
-                                            <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                                            <rect key="frame" x="0.0" y="0.0" width="393" height="852"/>
                                             <color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                                         </tableView>
                                     </subviews>

Examples/Maps/Maps/MainViewController.swift

@@ -156,6 +156,14 @@ class SearchPanelPhoneDelegate: NSObject, FloatingPanelControllerDelegate, UIGes
         self.owner = owner
     }
 
+    func floatingPanel(
+        _ fpc: FloatingPanelController,
+        shouldAllowToScroll scrollView: UIScrollView,
+        in state: FloatingPanelState
+    ) -> Bool {
+        return state == .full || state == .half
+    }
+
     func floatingPanel(_ vc: FloatingPanelController, layoutFor newCollection: UITraitCollection) -> FloatingPanelLayout {
         switch newCollection.verticalSizeClass {
         case .compact:
@@ -215,17 +223,10 @@ class SearchPanelLandscapeLayout: FloatingPanelLayout {
         .tip: FloatingPanelLayoutAnchor(absoluteInset: 69.0, edge: .bottom, referenceGuide: .safeArea),
     ]
     func prepareLayout(surfaceView: UIView, in view: UIView) -> [NSLayoutConstraint] {
-        if #available(iOS 11.0, *) {
-            return [
-                surfaceView.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor, constant: 8.0),
-                surfaceView.widthAnchor.constraint(equalToConstant: 291),
-            ]
-        } else {
-            return [
-                surfaceView.leftAnchor.constraint(equalTo: view.leftAnchor, constant: 8.0),
-                surfaceView.widthAnchor.constraint(equalToConstant: 291),
-            ]
-        }
+        return [
+            surfaceView.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor, constant: 8.0),
+            surfaceView.widthAnchor.constraint(equalToConstant: 291),
+        ]
     }
     func backdropAlpha(for state: FloatingPanelState) -> CGFloat {
         return 0.0

Examples/Maps/Maps/SearchViewController.swift

@@ -81,9 +81,6 @@ class SearchViewController: UIViewController, UITableViewDataSource {
 
     var items: [LocationItem] = []
 
-    // For iOS 10 only
-    private lazy var shadowLayer: CAShapeLayer = CAShapeLayer()
-
     override func viewDidLoad() {
         super.viewDidLoad()
         tableView.dataSource = self
@@ -92,29 +89,6 @@ class SearchViewController: UIViewController, UITableViewDataSource {
         hideHeader(animated: false)
     }
 
-    override func viewDidLayoutSubviews() {
-        super.viewDidLayoutSubviews()
-        if #available(iOS 11, *) {
-        } else {
-            // Exmaple: Add rounding corners on iOS 10
-            visualEffectView.layer.cornerRadius = 9.0
-            visualEffectView.clipsToBounds = true
-
-            // Exmaple: Add shadow manually on iOS 10
-            view.layer.insertSublayer(shadowLayer, at: 0)
-            let rect = visualEffectView.frame
-            let path = UIBezierPath(roundedRect: rect,
-                                    byRoundingCorners: [.topLeft, .topRight],
-                                    cornerRadii: CGSize(width: 9.0, height: 9.0))
-            shadowLayer.frame = visualEffectView.frame
-            shadowLayer.shadowPath = path.cgPath
-            shadowLayer.shadowColor = UIColor.black.cgColor
-            shadowLayer.shadowOffset = CGSize(width: 0.0, height: 1.0)
-            shadowLayer.shadowOpacity = 0.2
-            shadowLayer.shadowRadius = 3.0
-        }
-    }
-
     func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
         return items.count
     }
@@ -130,16 +104,16 @@ class SearchViewController: UIViewController, UITableViewDataSource {
     }
 
     func showHeader(animated: Bool) {
-        changeHeader(height: 116.0, aniamted: animated)
+        changeHeader(height: 116.0, animated: animated)
     }
 
     func hideHeader(animated: Bool) {
-        changeHeader(height: 0.0, aniamted: animated)
+        changeHeader(height: 0.0, animated: animated)
     }
 
-    private func changeHeader(height: CGFloat, aniamted: Bool) {
+    private func changeHeader(height: CGFloat, animated: Bool) {
         guard let headerView = tableView.tableHeaderView, headerView.bounds.height != height else { return }
-        if aniamted == false {
+        if animated == false {
             updateHeader(height: height)
             return
         }

Examples/Samples/Samples.xcodeproj/project.pbxproj

@@ -18,7 +18,7 @@
 		5442E24A25FC53C100A26F43 /* DebugTextViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5442E24925FC53C100A26F43 /* DebugTextViewController.swift */; };
 		5442E25225FC541700A26F43 /* NestedScrollViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5442E25125FC541700A26F43 /* NestedScrollViewController.swift */; };
 		54496C59263A7E5A0031E0C8 /* UseCaseController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54496C58263A7E5A0031E0C8 /* UseCaseController.swift */; };
-		544BC56826CC918200D0A436 /* AdaptiveLayoutTestViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 544BC56726CC918200D0A436 /* AdaptiveLayoutTestViewController.swift */; };
+		544BC56826CC918200D0A436 /* TableViewControllerForAdaptiveLayout.swift in Sources */ = {isa = PBXBuildFile; fileRef = 544BC56726CC918200D0A436 /* TableViewControllerForAdaptiveLayout.swift */; };
 		545DB9EE21511E6300CA77B8 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 545DB9ED21511E6300CA77B8 /* AppDelegate.swift */; };
 		545DB9F021511E6300CA77B8 /* MainViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 545DB9EF21511E6300CA77B8 /* MainViewController.swift */; };
 		545DB9F321511E6300CA77B8 /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 545DB9F121511E6300CA77B8 /* Main.storyboard */; };
@@ -30,8 +30,11 @@
 		549D23CC233C7779008EF4D7 /* FloatingPanel.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 549D23CA233C7779008EF4D7 /* FloatingPanel.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
 		54B51116216AFE5F0033A6F3 /* Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54B51115216AFE5F0033A6F3 /* Extensions.swift */; };
 		54CDC5D8215BBE23007D205C /* SupplementaryViews.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54CDC5D7215BBE23007D205C /* SupplementaryViews.swift */; };
+		54E58CB72BF8A8D900408EA9 /* CollectionViewControllerForAdaptiveLayout.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54E58CB62BF8A8D900408EA9 /* CollectionViewControllerForAdaptiveLayout.swift */; };
 		54EAD35B263A75EB006A36EA /* PanelLayouts.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54EAD35A263A75EB006A36EA /* PanelLayouts.swift */; };
 		54EAD365263A765F006A36EA /* PagePanelController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54EAD364263A765F006A36EA /* PagePanelController.swift */; };
+		54F185822BF4AD0000916F57 /* DebugListCollectionViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54F185812BF4AD0000916F57 /* DebugListCollectionViewController.swift */; };
+		54F185842BF4B82E00916F57 /* UnavailableViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54F185832BF4B82E00916F57 /* UnavailableViewController.swift */; };
 		5D82A6AD28D1843C006A44BA /* libswiftCoreGraphics.tbd in Frameworks */ = {isa = PBXBuildFile; fileRef = 5D82A6AC28D18438006A44BA /* libswiftCoreGraphics.tbd */; };
 /* End PBXBuildFile section */
 
@@ -61,7 +64,7 @@
 		5442E24925FC53C100A26F43 /* DebugTextViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DebugTextViewController.swift; sourceTree = "<group>"; };
 		5442E25125FC541700A26F43 /* NestedScrollViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NestedScrollViewController.swift; sourceTree = "<group>"; };
 		54496C58263A7E5A0031E0C8 /* UseCaseController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UseCaseController.swift; sourceTree = "<group>"; };
-		544BC56726CC918200D0A436 /* AdaptiveLayoutTestViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AdaptiveLayoutTestViewController.swift; sourceTree = "<group>"; };
+		544BC56726CC918200D0A436 /* TableViewControllerForAdaptiveLayout.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TableViewControllerForAdaptiveLayout.swift; sourceTree = "<group>"; };
 		545DB9EA21511E6300CA77B8 /* Samples.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = Samples.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		545DB9ED21511E6300CA77B8 /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		545DB9EF21511E6300CA77B8 /* MainViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MainViewController.swift; sourceTree = "<group>"; };
@@ -74,8 +77,11 @@
 		549D23CA233C7779008EF4D7 /* FloatingPanel.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = FloatingPanel.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		54B51115216AFE5F0033A6F3 /* Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Extensions.swift; sourceTree = "<group>"; };
 		54CDC5D7215BBE23007D205C /* SupplementaryViews.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SupplementaryViews.swift; sourceTree = "<group>"; };
+		54E58CB62BF8A8D900408EA9 /* CollectionViewControllerForAdaptiveLayout.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CollectionViewControllerForAdaptiveLayout.swift; sourceTree = "<group>"; };
 		54EAD35A263A75EB006A36EA /* PanelLayouts.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PanelLayouts.swift; sourceTree = "<group>"; };
 		54EAD364263A765F006A36EA /* PagePanelController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PagePanelController.swift; sourceTree = "<group>"; };
+		54F185812BF4AD0000916F57 /* DebugListCollectionViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DebugListCollectionViewController.swift; sourceTree = "<group>"; };
+		54F185832BF4B82E00916F57 /* UnavailableViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UnavailableViewController.swift; sourceTree = "<group>"; };
 		5D82A6AC28D18438006A44BA /* libswiftCoreGraphics.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = libswiftCoreGraphics.tbd; path = usr/lib/swift/libswiftCoreGraphics.tbd; sourceTree = SDKROOT; };
 /* End PBXFileReference section */
 
@@ -95,17 +101,18 @@
 		5442E22225FC519700A26F43 /* ContentViewControllers */ = {
 			isa = PBXGroup;
 			children = (
+				54E58CB52BF8A88600408EA9 /* AdaptiveLayout */,
 				5442E23F25FC533800A26F43 /* DebugTableViewController.swift */,
 				5442E24925FC53C100A26F43 /* DebugTextViewController.swift */,
+				54F185812BF4AD0000916F57 /* DebugListCollectionViewController.swift */,
 				5442E23325FC528400A26F43 /* DetailViewController.swift */,
 				5442E24325FC538200A26F43 /* InspectorViewController.swift */,
-				5442E22325FC51AF00A26F43 /* ImageViewController.swift */,
 				5442E25125FC541700A26F43 /* NestedScrollViewController.swift */,
 				5442E23925FC52CD00A26F43 /* ModalViewController.swift */,
 				5442E22725FC51E200A26F43 /* MultiPanelController.swift */,
 				5442E22B25FC521F00A26F43 /* SettingsViewController.swift */,
 				5442E22F25FC525200A26F43 /* TabBarViewController.swift */,
-				544BC56726CC918200D0A436 /* AdaptiveLayoutTestViewController.swift */,
+				54F185832BF4B82E00916F57 /* UnavailableViewController.swift */,
 			);
 			path = ContentViewControllers;
 			sourceTree = "<group>";
@@ -157,6 +164,16 @@
 			path = UseCases;
 			sourceTree = "<group>";
 		};
+		54E58CB52BF8A88600408EA9 /* AdaptiveLayout */ = {
+			isa = PBXGroup;
+			children = (
+				5442E22325FC51AF00A26F43 /* ImageViewController.swift */,
+				544BC56726CC918200D0A436 /* TableViewControllerForAdaptiveLayout.swift */,
+				54E58CB62BF8A8D900408EA9 /* CollectionViewControllerForAdaptiveLayout.swift */,
+			);
+			path = AdaptiveLayout;
+			sourceTree = "<group>";
+		};
 		5D82A6AB28D18438006A44BA /* Frameworks */ = {
 			isa = PBXGroup;
 			children = (
@@ -238,15 +255,17 @@
 			buildActionMask = 2147483647;
 			files = (
 				5442E23425FC528400A26F43 /* DetailViewController.swift in Sources */,
+				54E58CB72BF8A8D900408EA9 /* CollectionViewControllerForAdaptiveLayout.swift in Sources */,
 				54496C59263A7E5A0031E0C8 /* UseCaseController.swift in Sources */,
 				54CDC5D8215BBE23007D205C /* SupplementaryViews.swift in Sources */,
 				54B51116216AFE5F0033A6F3 /* Extensions.swift in Sources */,
-				544BC56826CC918200D0A436 /* AdaptiveLayoutTestViewController.swift in Sources */,
+				544BC56826CC918200D0A436 /* TableViewControllerForAdaptiveLayout.swift in Sources */,
 				5442E24A25FC53C100A26F43 /* DebugTextViewController.swift in Sources */,
 				546341AC25C6426500CA0596 /* CustomState.swift in Sources */,
 				5442E23A25FC52CD00A26F43 /* ModalViewController.swift in Sources */,
 				5442E22425FC51AF00A26F43 /* ImageViewController.swift in Sources */,
 				5442E24025FC533800A26F43 /* DebugTableViewController.swift in Sources */,
+				54F185822BF4AD0000916F57 /* DebugListCollectionViewController.swift in Sources */,
 				5442E25225FC541700A26F43 /* NestedScrollViewController.swift in Sources */,
 				5442E22825FC51E200A26F43 /* MultiPanelController.swift in Sources */,
 				546341A125C6415100CA0596 /* UseCase.swift in Sources */,
@@ -257,6 +276,7 @@
 				54EAD365263A765F006A36EA /* PagePanelController.swift in Sources */,
 				5442E24425FC538200A26F43 /* InspectorViewController.swift in Sources */,
 				5442E22C25FC521F00A26F43 /* SettingsViewController.swift in Sources */,
+				54F185842BF4B82E00916F57 /* UnavailableViewController.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

Examples/Samples/Sources/Base.lproj/Main.storyboard

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="21701" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="RoN-h0-uBD">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="32700.99.1234" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="RoN-h0-uBD">
     <device id="retina6_1" orientation="portrait" appearance="light"/>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="21679"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="22685"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="Stack View standard spacing" minToolsVersion="9.0"/>
         <capability name="System colors in document resources" minToolsVersion="11.0"/>
@@ -801,10 +801,10 @@ Section 1.10.33 of "de Finibus Bonorum et Malorum", written by Cicero in 45 BC
             </objects>
             <point key="canvasLocation" x="-2.1739130434782612" y="733.92857142857144"/>
         </scene>
-        <!--Adaptive Layout Test View Controller-->
+        <!--Table View Controller For Adaptive Layout-->
         <scene sceneID="rDI-lU-wEx">
             <objects>
-                <viewController storyboardIdentifier="AdaptiveLayoutTestViewController" id="5nC-6E-bXf" customClass="AdaptiveLayoutTestViewController" customModule="Samples" customModuleProvider="target" sceneMemberID="viewController">
+                <viewController storyboardIdentifier="TableViewControllerForAdaptiveLayout" id="5nC-6E-bXf" customClass="TableViewControllerForAdaptiveLayout" customModule="Samples" customModuleProvider="target" sceneMemberID="viewController">
                     <view key="view" contentMode="scaleToFill" id="jXL-Ss-NCJ">
                         <rect key="frame" x="0.0" y="0.0" width="375" height="778"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
@@ -861,13 +861,13 @@ Section 1.10.33 of "de Finibus Bonorum et Malorum", written by Cicero in 45 BC
             <color white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
         </systemColor>
         <systemColor name="systemOrangeColor">
-            <color red="1" green="0.58431372549019611" blue="0.0" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+            <color red="1" green="0.58431372550000005" blue="0.0" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
         </systemColor>
         <systemColor name="systemPurpleColor">
-            <color red="0.68627450980392157" green="0.32156862745098042" blue="0.87058823529411766" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+            <color red="0.68627450980000004" green="0.32156862749999998" blue="0.87058823529999996" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
         </systemColor>
         <systemColor name="systemTealColor">
-            <color red="0.18823529411764706" green="0.69019607843137254" blue="0.7803921568627451" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+            <color red="0.18823529410000001" green="0.69019607839999997" blue="0.78039215689999997" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
         </systemColor>
     </resources>
 </document>

Examples/Samples/Sources/ContentViewControllers/AdaptiveLayout/CollectionViewControllerForAdaptiveLayout.swift

@@ -0,0 +1,175 @@
+// Copyright 2018-Present Shin Yamamoto. All rights reserved. MIT license.
+
+import UIKit
+import FloatingPanel
+
+@available(iOS 13.0, *)
+class CollectionViewControllerForAdaptiveLayout: UIViewController {
+    class PanelLayout: FloatingPanelLayout {
+        let position: FloatingPanelPosition = .bottom
+        let initialState: FloatingPanelState = .full
+
+        private unowned var targetGuide: UILayoutGuide
+
+        init(targetGuide: UILayoutGuide) {
+            self.targetGuide = targetGuide
+        }
+
+        var anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] {
+            return [
+                .full: FloatingPanelAdaptiveLayoutAnchor(
+                    absoluteOffset: 0.0,
+                    contentLayout: targetGuide,
+                    referenceGuide: .superview,
+                    contentBoundingGuide: .safeArea
+                ),
+                .half: FloatingPanelAdaptiveLayoutAnchor(
+                    fractionalOffset: 0.5,
+                    contentLayout: targetGuide,
+                    referenceGuide: .superview,
+                    contentBoundingGuide: .safeArea
+                ),
+            ]
+        }
+    }
+
+    enum LayoutType {
+        case flow
+        case compositional
+    }
+
+    weak var collectionView: UICollectionView!
+    var layoutType: LayoutType = .flow
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        setupCollectionView()
+    }
+
+    private func setupCollectionView() {
+        let collectionViewLayout = {
+            switch layoutType {
+            case .flow:
+                CollectionViewLayoutFactory.flowLayout
+            case .compositional:
+                CollectionViewLayoutFactory.compositionalLayout
+            }
+        }()
+        let collectionView = IntrinsicCollectionView(
+            frame: .zero,
+            collectionViewLayout: collectionViewLayout
+        )
+
+        collectionView.delegate = self
+        collectionView.dataSource = self
+        collectionView.backgroundColor = .yellow
+        collectionView.register(Cell.self, forCellWithReuseIdentifier: Cell.reuseIdentifier)
+
+        view.addSubview(collectionView)
+        self.collectionView = collectionView
+
+        collectionView.translatesAutoresizingMaskIntoConstraints = false
+        NSLayoutConstraint.activate([
+            collectionView.topAnchor.constraint(equalTo: view.topAnchor),
+            collectionView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
+            collectionView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
+            collectionView.trailingAnchor.constraint(equalTo: view.trailingAnchor)
+        ])
+    }
+}
+
+@available(iOS 13.0, *)
+extension CollectionViewControllerForAdaptiveLayout: UICollectionViewDataSource, UICollectionViewDelegateFlowLayout {
+    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
+        return 5  // Only three cells needed to fill the space
+    }
+
+    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
+        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: Cell.reuseIdentifier, for: indexPath) as! Cell
+        cell.configure(text: "Item \(indexPath.row)")
+        return cell
+    }
+
+
+    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
+        let width = collectionView.frame.width  
+        return CGSize(width: width, height: 100)
+    }
+}
+
+@available(iOS 13.0, *)
+extension CollectionViewControllerForAdaptiveLayout {
+    enum CollectionViewLayoutFactory {
+        static var flowLayout: UICollectionViewLayout {
+            let layout = UICollectionViewFlowLayout()
+            layout.scrollDirection = .vertical
+            layout.minimumLineSpacing = 8  // Vertical spacing between rows
+            return layout
+        }
+
+        @available(iOS 13.0, *)
+        static var compositionalLayout: UICollectionViewLayout {
+            UICollectionViewCompositionalLayout { (sectionIndex: Int, layoutEnvironment: NSCollectionLayoutEnvironment) -> NSCollectionLayoutSection? in
+                let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1.0), heightDimension: .absolute(100))
+                let item = NSCollectionLayoutItem(layoutSize: itemSize)
+
+                let group = NSCollectionLayoutGroup.horizontal(layoutSize: itemSize, subitems: [item])
+
+                let section = NSCollectionLayoutSection(group: group)
+                section.interGroupSpacing = 8 // Spacing between each group/item
+                section.contentInsets = NSDirectionalEdgeInsets(top: 0, leading: 0, bottom: 0, trailing: 0)
+
+                return section
+            }
+        }
+    }
+
+
+    private final class Cell: UICollectionViewCell {
+        static let reuseIdentifier = "Cell"
+
+        private let label: UILabel = {
+            let label = UILabel()
+            label.textAlignment = .center
+            label.textColor = .white
+            return label
+        }()
+
+        override init(frame: CGRect) {
+            super.init(frame: frame)
+            commonInit()
+        }
+
+        required init?(coder: NSCoder) {
+            super.init(coder: coder)
+            commonInit()
+        }
+
+        private func commonInit() {
+            backgroundColor = .systemBlue
+            addSubview(label)
+            label.translatesAutoresizingMaskIntoConstraints = false
+            NSLayoutConstraint.activate([
+                label.centerXAnchor.constraint(equalTo: centerXAnchor),
+                label.centerYAnchor.constraint(equalTo: centerYAnchor)
+            ])
+        }
+
+        func configure(text: String) {
+            label.text = text
+        }
+    }
+
+    private final class IntrinsicCollectionView: UICollectionView {
+        override public var contentSize: CGSize {
+            didSet {
+                invalidateIntrinsicContentSize()
+            }
+        }
+
+        override public var intrinsicContentSize: CGSize {
+            layoutIfNeeded()
+            return CGSize(width: UIView.noIntrinsicMetric, height: contentSize.height)
+        }
+    }
+}

Examples/Samples/Sources/ContentViewControllers/AdaptiveLayout/ImageViewController.swift

@@ -37,7 +37,6 @@ final class ImageViewController: UIViewController {
         case withHeaderFooter
     }
 
-    @available(iOS 11.0, *)
     func layoutGuideFor(mode: Mode) -> UILayoutGuide {
         switch mode {
         case .onlyImage:

Examples/Samples/Sources/ContentViewControllers/AdaptiveLayout/TableViewControllerForAdaptiveLayout.swift

@@ -3,7 +3,7 @@
 import UIKit
 import FloatingPanel
 
-final class AdaptiveLayoutTestViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
+final class TableViewControllerForAdaptiveLayout: UIViewController, UITableViewDataSource, UITableViewDelegate {
     class PanelLayout: FloatingPanelLayout {
         let position: FloatingPanelPosition = .bottom
         let initialState: FloatingPanelState = .full
@@ -75,7 +75,6 @@ final class AdaptiveLayoutTestViewController: UIViewController, UITableViewDataS
 }
 
 class IntrinsicTableView: UITableView {
-
     override var contentSize:CGSize {
         didSet {
             invalidateIntrinsicContentSize()

Examples/Samples/Sources/ContentViewControllers/DebugListCollectionViewController.swift

@@ -0,0 +1,77 @@
+// Copyright 2018 the FloatingPanel authors. All rights reserved. MIT license.
+
+import UIKit
+
+@available(iOS 14, *)
+class DebugListCollectionViewController: UIViewController {
+
+    enum Section {
+        case main
+    }
+
+    var dataSource: UICollectionViewDiffableDataSource<Section, Int>! = nil
+    var collectionView: UICollectionView! = nil
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        navigationItem.title = "List"
+        configureHierarchy()
+        configureDataSource()
+    }
+}
+
+@available(iOS 14, *)
+extension DebugListCollectionViewController {
+    /// - Tag: List
+    private func createLayout() -> UICollectionViewLayout {
+        var config = UICollectionLayoutListConfiguration(appearance: .insetGrouped)
+        config.trailingSwipeActionsConfigurationProvider =  { indexPath -> UISwipeActionsConfiguration? in
+            return UISwipeActionsConfiguration(
+                actions: [UIContextualAction(
+                    style: .destructive,
+                    title: "Delete",
+                    handler: { _, _, completion in
+                        // Do nothing now
+                    }
+                )]
+            )
+        }
+        return UICollectionViewCompositionalLayout.list(using: config)
+    }
+}
+
+@available(iOS 14, *)
+extension DebugListCollectionViewController {
+    private func configureHierarchy() {
+        collectionView = UICollectionView(frame: view.bounds, collectionViewLayout: createLayout())
+        collectionView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
+        view.addSubview(collectionView)
+        collectionView.delegate = self
+    }
+    private func configureDataSource() {
+
+        let cellRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, Int> { (cell, indexPath, item) in
+            var content = cell.defaultContentConfiguration()
+            content.text = "\(item)"
+            cell.contentConfiguration = content
+        }
+
+        dataSource = UICollectionViewDiffableDataSource<Section, Int>(collectionView: collectionView) {
+            (collectionView: UICollectionView, indexPath: IndexPath, identifier: Int) -> UICollectionViewCell? in
+
+            return collectionView.dequeueConfiguredReusableCell(using: cellRegistration, for: indexPath, item: identifier)
+        }
+
+        var snapshot = NSDiffableDataSourceSnapshot<Section, Int>()
+        snapshot.appendSections([.main])
+        snapshot.appendItems(Array(0..<94))
+        dataSource.apply(snapshot, animatingDifferences: false)
+    }
+}
+
+@available(iOS 14, *)
+extension DebugListCollectionViewController: UICollectionViewDelegate {
+    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
+        collectionView.deselectItem(at: indexPath, animated: true)
+    }
+}

Examples/Samples/Sources/ContentViewControllers/DebugTextViewController.swift

@@ -11,9 +11,7 @@ final class DebugTextViewController: UIViewController, UITextViewDelegate {
         textView.delegate = self
         print("viewDidLoad: TextView --- ", textView.contentOffset, textView.contentInset)
 
-        if #available(iOS 11.0, *) {
-            textView.contentInsetAdjustmentBehavior = .never
-        }
+        textView.contentInsetAdjustmentBehavior = .never
     }
 
     override func viewWillLayoutSubviews() {
@@ -32,9 +30,7 @@ final class DebugTextViewController: UIViewController, UITextViewDelegate {
 
     func scrollViewDidScroll(_ scrollView: UIScrollView) {
         print("TextView --- ", scrollView.contentOffset, scrollView.contentInset)
-        if #available(iOS 11.0, *) {
-            print("TextView --- ", scrollView.adjustedContentInset)
-        }
+        print("TextView --- ", scrollView.adjustedContentInset)
     }
 
     @IBAction func toggleTopMargin(_ sender: UISwitch) {

Examples/Samples/Sources/ContentViewControllers/SettingsViewController.swift

@@ -14,21 +14,17 @@ final class SettingsViewController: InspectableViewController {
 
     override func viewDidLayoutSubviews() {
         super.viewDidLayoutSubviews()
-        if #available(iOS 11.0, *) {
-            let prefersLargeTitles = navigationController!.navigationBar.prefersLargeTitles
-            largeTitlesSwitch.setOn(prefersLargeTitles, animated: false)
-        } else {
-            largeTitlesSwitch.isEnabled = false
-        }
+        let prefersLargeTitles = navigationController!.navigationBar.prefersLargeTitles
+        largeTitlesSwitch.setOn(prefersLargeTitles, animated: false)
+
         let isTranslucent = navigationController!.navigationBar.isTranslucent
         translucentSwitch.setOn(isTranslucent, animated: false)
     }
 
     @IBAction func toggleLargeTitle(_ sender: UISwitch) {
-        if #available(iOS 11.0, *) {
-            navigationController?.navigationBar.prefersLargeTitles = sender.isOn
-        }
+        navigationController?.navigationBar.prefersLargeTitles = sender.isOn
     }
+
     @IBAction func toggleTranslucent(_ sender: UISwitch) {
         // White non-translucent navigation bar, supports dark appearance
         if #available(iOS 15, *) {

Examples/Samples/Sources/ContentViewControllers/TabBarViewController.swift

@@ -238,13 +238,8 @@ class ThreeTabBarPanelLayout: FloatingPanelLayout {
     }
 
     func prepareLayout(surfaceView: UIView, in view: UIView) -> [NSLayoutConstraint] {
-        if #available(iOS 11.0, *) {
-            leftConstraint = surfaceView.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor, constant: 0.0)
-            rightConstraint = surfaceView.rightAnchor.constraint(equalTo: view.safeAreaLayoutGuide.rightAnchor, constant: 0.0)
-        } else {
-            leftConstraint = surfaceView.leftAnchor.constraint(equalTo: view.leftAnchor, constant: 0.0)
-            rightConstraint = surfaceView.rightAnchor.constraint(equalTo: view.rightAnchor, constant: 0.0)
-        }
+        leftConstraint = surfaceView.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor, constant: 0.0)
+        rightConstraint = surfaceView.rightAnchor.constraint(equalTo: view.safeAreaLayoutGuide.rightAnchor, constant: 0.0)
         return [ leftConstraint, rightConstraint ]
     }
 }

Examples/Samples/Sources/ContentViewControllers/UnavailableViewController.swift

@@ -0,0 +1,24 @@
+// Copyright 2018 the FloatingPanel authors. All rights reserved. MIT license.
+
+import UIKit
+
+class UnavailableViewController: UIViewController {
+    weak var label: UILabel!
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        let label = UILabel()
+        label.text = "Unavailable content"
+        label.numberOfLines = 0
+        label.textAlignment = .center
+        label.frame = view.bounds
+        label.autoresizingMask = [
+            .flexibleTopMargin,
+            .flexibleLeftMargin,
+            .flexibleBottomMargin,
+            .flexibleRightMargin
+        ]
+        view.addSubview(label)
+        self.label = label
+    }
+}

Examples/Samples/Sources/Extensions.swift

@@ -33,22 +33,10 @@ class CustomLayoutGuide: LayoutGuideProvider {
 
 extension UIViewController {
     var layoutInsets: UIEdgeInsets {
-        if #available(iOS 11.0, *) {
-            return view.safeAreaInsets
-        } else {
-            return UIEdgeInsets(top: topLayoutGuide.length,
-                                left: 0.0,
-                                bottom: bottomLayoutGuide.length,
-                                right: 0.0)
-        }
+        return view.safeAreaInsets
     }
 
     var layoutGuide: LayoutGuideProvider {
-        if #available(iOS 11.0, *) {
-            return view!.safeAreaLayoutGuide
-        } else {
-            return CustomLayoutGuide(topAnchor: topLayoutGuide.bottomAnchor,
-                                     bottomAnchor: bottomLayoutGuide.topAnchor)
-        }
+        return view.safeAreaLayoutGuide
     }
 }

Examples/Samples/Sources/MainViewController.swift

@@ -15,14 +15,11 @@ extension MainViewController {
         tableView.dataSource = self
         tableView.delegate = self
         tableView.register(UITableViewCell.self, forCellReuseIdentifier: "Cell")
-        automaticallyAdjustsScrollViewInsets = false
 
         let searchController = UISearchController(searchResultsController: nil)
-        if #available(iOS 11.0, *) {
-            navigationItem.searchController = searchController
-            navigationItem.hidesSearchBarWhenScrolling = false
-            navigationItem.largeTitleDisplayMode = .automatic
-        }
+        navigationItem.searchController = searchController
+        navigationItem.hidesSearchBarWhenScrolling = false
+        navigationItem.largeTitleDisplayMode = .automatic
         var insets = UIEdgeInsets.zero
         insets.bottom += 69.0
         tableView.contentInset = insets
@@ -33,12 +30,10 @@ extension MainViewController {
 
     override func viewDidAppear(_ animated: Bool) {
         super.viewDidAppear(animated)
-        if #available(iOS 11.0, *) {
-            if let observation = navigationController?.navigationBar.observe(\.prefersLargeTitles, changeHandler: { (bar, _) in
-                self.tableView.reloadData()
-            }) {
-                observations.append(observation)
-            }
+        if let observation = navigationController?.navigationBar.observe(\.prefersLargeTitles, changeHandler: { (bar, _) in
+            self.tableView.reloadData()
+        }) {
+            observations.append(observation)
         }
     }
 
@@ -56,12 +51,8 @@ extension MainViewController {
 
 extension MainViewController: UITableViewDataSource {
     func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
-        if #available(iOS 11.0, *) {
-            if navigationController?.navigationBar.prefersLargeTitles == true {
-                return UseCase.allCases.count + 30
-            } else {
-                return UseCase.allCases.count
-            }
+        if navigationController?.navigationBar.prefersLargeTitles == true {
+            return UseCase.allCases.count + 30
         } else {
             return UseCase.allCases.count
         }

Examples/Samples/Sources/UseCases/UseCase.swift

@@ -5,6 +5,7 @@ import UIKit
 enum UseCase: Int, CaseIterable {
     case trackingTableView
     case trackingTextView
+    case trackingCollectionViewList
     case showDetail
     case showModal
     case showPanelModal
@@ -22,14 +23,18 @@ enum UseCase: Int, CaseIterable {
     case showNavigationController
     case showTopPositionedPanel
     case showAdaptivePanel
-    case showAdaptivePanelWithCustomGuide
+    case showAdaptivePanelWithTableView
+    case showAdaptivePanelWithCollectionView
+    case showAdaptivePanelWithCompositionalCollectionView
     case showCustomStatePanel
+    case showCustomBackdrop
 }
 
 extension UseCase {
     var name: String {
         switch self {
         case .trackingTableView: return "Scroll tracking(TableView)"
+        case .trackingCollectionViewList: return "Scroll tracking(List CollectionView)"
         case .trackingTextView: return "Scroll tracking(TextView)"
         case .showDetail: return "Show Detail Panel"
         case .showModal: return "Show Modal"
@@ -48,8 +53,11 @@ extension UseCase {
         case .showNavigationController: return "Show Navigation Controller"
         case .showTopPositionedPanel: return "Show Top Positioned Panel"
         case .showAdaptivePanel: return "Show Adaptive Panel"
-        case .showAdaptivePanelWithCustomGuide: return "Show Adaptive Panel (Custom Layout Guide)"
+        case .showAdaptivePanelWithTableView: return "Show Adaptive Panel (TableView)"
+        case .showAdaptivePanelWithCollectionView: return "Show Adaptive Panel (CollectionView)"
+        case .showAdaptivePanelWithCompositionalCollectionView: return "Show Adaptive Panel (Compositional CollectionView)"
         case .showCustomStatePanel: return "Show Panel with Custom state"
+        case .showCustomBackdrop: return "Show Panel with Custom Backdrop"
         }
     }
 }
@@ -63,6 +71,13 @@ extension UseCase {
     private var content: Content {
         switch self {
         case .trackingTableView: return .viewController(DebugTableViewController())
+        case .trackingCollectionViewList:
+            if #available(iOS 14, *) {
+                return .viewController(DebugListCollectionViewController())
+            } else {
+                let msg = "UICollectionLayoutListConfiguration is unavailable.\nBuild this app on iOS 14 and later."
+                return makeUnavailableViewContent(message: msg)
+            }
         case .trackingTextView: return .storyboard("ConsoleViewController") // Storyboard only
         case .showDetail: return .storyboard(String(describing: DetailViewController.self))
         case .showModal: return .storyboard(String(describing: ModalViewController.self))
@@ -81,8 +96,19 @@ extension UseCase {
         case .showNavigationController: return .storyboard("RootNavigationController") // Storyboard only
         case .showTopPositionedPanel: return .viewController(DebugTableViewController())
         case .showAdaptivePanel: return .storyboard(String(describing: ImageViewController.self))
-        case .showAdaptivePanelWithCustomGuide: return .storyboard(String(describing: AdaptiveLayoutTestViewController.self))
+        case .showAdaptivePanelWithTableView: return .storyboard(String(describing: TableViewControllerForAdaptiveLayout.self))
+        case .showAdaptivePanelWithCollectionView,
+            .showAdaptivePanelWithCompositionalCollectionView:
+            if #available(iOS 13, *) {
+                let vc = CollectionViewControllerForAdaptiveLayout()
+                vc.layoutType = self == .showAdaptivePanelWithCollectionView ? .flow : .compositional
+                return .viewController(vc)
+            } else {
+                let msg = "Compositional layout is unavailable.\nBuild this app on iOS 13 and later."
+                return makeUnavailableViewContent(message: msg)
+            }
         case .showCustomStatePanel: return .viewController(DebugTableViewController())
+        case .showCustomBackdrop: return .viewController(UIViewController())
         }
     }
 
@@ -95,4 +121,11 @@ extension UseCase {
             return vc
         }
     }
+
+    private func makeUnavailableViewContent(message: String) -> Content {
+        let vc = UnavailableViewController()
+        vc.loadViewIfNeeded()
+        vc.label.text = message
+        return .viewController(vc)
+    }
 }

Examples/Samples/Sources/UseCases/UseCaseController.swift

@@ -52,6 +52,30 @@ extension UseCaseController {
             fpc.ext_trackScrollView(in: contentVC)
             addMain(panel: fpc)
 
+         case .trackingCollectionViewList:
+            let fpc = FloatingPanelController()
+            fpc.delegate = self
+            fpc.contentInsetAdjustmentBehavior = .always
+            fpc.surfaceView.appearance = {
+                let appearance = SurfaceAppearance()
+                appearance.cornerRadius = 6.0
+                return appearance
+            }()
+
+            let tapGesture = UITapGestureRecognizer(target: self, action: #selector(UseCaseController.handleSurface(tapGesture:)))
+            tapGesture.cancelsTouchesInView = false
+            tapGesture.numberOfTapsRequired = 2
+            // Prevents a delay to response a tap in menus of DebugTableViewController.
+            tapGesture.delaysTouchesEnded = false
+            fpc.surfaceView.addGestureRecognizer(tapGesture)
+
+            fpc.set(contentViewController: contentVC)
+            if #available(iOS 14, *),
+                let scrollView = (fpc.contentViewController as? DebugListCollectionViewController)?.collectionView {
+                    fpc.track(scrollView: scrollView)
+            }
+            addMain(panel: fpc)
+
         case .trackingTextView:
             let fpc = FloatingPanelController()
             fpc.delegate = self
@@ -239,13 +263,13 @@ extension UseCaseController {
             fpc.set(contentViewController: contentVC)
             fpc.ext_trackScrollView(in: contentVC)
             if case let contentVC as ImageViewController = contentVC {
-                let mode: ImageViewController.Mode = (useCase == .showAdaptivePanelWithCustomGuide) ? .withHeaderFooter : .onlyImage
+                let mode: ImageViewController.Mode = (useCase == .showAdaptivePanelWithTableView) ? .withHeaderFooter : .onlyImage
                 let layoutGuide = contentVC.layoutGuideFor(mode: mode)
                 fpc.layout = ImageViewController.PanelLayout(targetGuide: layoutGuide)
             }
             addMain(panel: fpc)
 
-        case .showAdaptivePanelWithCustomGuide:
+        case .showAdaptivePanelWithTableView:
             let fpc = FloatingPanelController()
             fpc.isRemovalInteractionEnabled = true
             fpc.contentInsetAdjustmentBehavior = .always
@@ -255,10 +279,25 @@ extension UseCaseController {
                 return appearance
             }()
 
-
             fpc.set(contentViewController: contentVC)
-            fpc.ext_trackScrollView(in: contentVC)
-            fpc.layout = AdaptiveLayoutTestViewController.PanelLayout(targetGuide: contentVC.view.makeBoundsLayoutGuide())
+            fpc.track(scrollView: (contentVC as! TableViewControllerForAdaptiveLayout).tableView)
+            fpc.layout = TableViewControllerForAdaptiveLayout.PanelLayout(targetGuide: contentVC.view.makeBoundsLayoutGuide())
+            addMain(panel: fpc)
+
+        case .showAdaptivePanelWithCollectionView, .showAdaptivePanelWithCompositionalCollectionView:
+            let fpc = FloatingPanelController()
+            fpc.isRemovalInteractionEnabled = true
+            fpc.contentInsetAdjustmentBehavior = .always
+            fpc.surfaceView.appearance = {
+                let appearance = SurfaceAppearance()
+                appearance.cornerRadius = 6.0
+                return appearance
+            }()
+            fpc.set(contentViewController: contentVC)
+            if #available(iOS 13, *) {
+                fpc.track(scrollView: (contentVC as! CollectionViewControllerForAdaptiveLayout).collectionView)
+                fpc.layout = CollectionViewControllerForAdaptiveLayout.PanelLayout(targetGuide: contentVC.view.makeBoundsLayoutGuide())
+            }
             addMain(panel: fpc)
 
         case .showCustomStatePanel:
@@ -273,6 +312,52 @@ extension UseCaseController {
             fpc.set(contentViewController: contentVC)
             fpc.ext_trackScrollView(in: contentVC)
             addMain(panel: fpc)
+
+        case .showCustomBackdrop:
+            class BlurBackdropView: BackdropView {
+                var effectView: UIVisualEffectView!
+                override var alpha: CGFloat {
+                    set {
+                        effectView.alpha = newValue
+                    }
+                    get {
+                        effectView.alpha
+                    }
+                }
+                override init() {
+                    super.init()
+
+                    let effect = UIBlurEffect(style: .prominent)
+                    let effectView = UIVisualEffectView(effect: effect)
+                    addSubview(effectView)
+                    effectView.frame = bounds
+                    effectView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
+                    self.effectView = effectView
+                }
+
+                required init?(coder: NSCoder) {
+                    fatalError("init(coder:) has not been implemented")
+                }
+            }
+            class CustomBottomLayout: FloatingPanelBottomLayout {
+                override var anchors: [FloatingPanelState: FloatingPanelLayoutAnchoring]  {
+                    return [
+                        .full: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .top, referenceGuide: .safeArea),
+                        .half: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .safeArea),
+                        .tip: FloatingPanelLayoutAnchor(fractionalInset: 0.1, edge: .bottom, referenceGuide: .safeArea),
+                    ]
+                }
+                override func backdropAlpha(for state: FloatingPanelState) -> CGFloat {
+                    return state == .full ? 0.8 : 0.0
+                }
+            }
+
+            let fpc = FloatingPanelController()
+            fpc.delegate = self
+            fpc.set(contentViewController: contentVC)
+            fpc.backdropView = BlurBackdropView()
+            fpc.layout = CustomBottomLayout()
+            addMain(panel: fpc)
         }
     }
 
@@ -322,8 +407,16 @@ extension UseCaseController {
 }
 
 extension UseCaseController: FloatingPanelControllerDelegate {
+    func floatingPanel(
+        _ fpc: FloatingPanelController,
+        shouldAllowToScroll scrollView: UIScrollView,
+        in state: FloatingPanelState
+    ) -> Bool {
+        return state == .full || state == .half
+    }
+
     func floatingPanel(_ vc: FloatingPanelController, contentOffsetForPinning trackingScrollView: UIScrollView) -> CGPoint {
-        if useCase == .showNavigationController, #available(iOS 11.0, *) {
+        if useCase == .showNavigationController {
             // 148.0 is the SafeArea's top value for a navigation bar with a large title.
             return CGPoint(x: 0.0, y: 0.0 - trackingScrollView.contentInset.top - 148.0)
         }
@@ -404,7 +497,7 @@ private extension FloatingPanelController {
         case let contentVC as ImageViewController:
             track(scrollView: contentVC.scrollView)
 
-        case let contentVC as AdaptiveLayoutTestViewController:
+        case let contentVC as TableViewControllerForAdaptiveLayout:
             track(scrollView: contentVC.tableView)
 
         default:

Examples/Stocks/Stocks/MainViewController.swift

@@ -81,7 +81,7 @@ class MainViewController: UIViewController, FloatingPanelControllerDelegate {
     }
 
     private func hideStockTickerBanner() {
-        // Dimiss top bar with dissolve animation
+        // Dismiss top bar with dissolve animation
         UIView.animate(withDuration: 0.25) {
             self.topBannerView.alpha = 0.0
             self.labelStackView.alpha = 1.0

FloatingPanel.podspec

@@ -1,18 +1,18 @@
 Pod::Spec.new do |s|
 
   s.name                = "FloatingPanel"
-  s.version             = "2.7.0"
+  s.version             = "2.8.6"
   s.summary             = "FloatingPanel is a clean and easy-to-use UI component of a floating panel interface."
   s.description         = <<-DESC
 FloatingPanel is a clean and easy-to-use UI component for a new interface introduced in Apple Maps, Shortcuts and Stocks app.
 The new interface displays the related contents and utilities in parallel as a user wants.
                    DESC
-  s.homepage            = "https://github.com/SCENEE/FloatingPanel"
+  s.homepage            = "https://github.com/scenee/FloatingPanel"
   s.author              = "Shin Yamamoto"
   s.social_media_url    = "https://twitter.com/scenee"
 
-  s.platform            = :ios, "10.0"
-  s.source              = { :git => "https://github.com/SCENEE/FloatingPanel.git", :tag => s.version.to_s }
+  s.platform            = :ios, "11.0"
+  s.source              = { :git => "https://github.com/scenee/FloatingPanel.git", :tag => s.version.to_s }
   s.source_files        = "Sources/*.swift"
   s.swift_version       = '5.0'
 

FloatingPanel.xcodeproj/project.pbxproj

@@ -462,12 +462,13 @@
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				INFOPLIST_FILE = Sources/Info.plist;
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
-				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 11.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = "$(RECOMMENDED_MACOSX_DEPLOYMENT_TARGET)";
 				PRODUCT_BUNDLE_IDENTIFIER = com.scenee.FloatingPanel;
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SKIP_INSTALL = YES;
@@ -493,12 +494,13 @@
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				INFOPLIST_FILE = Sources/Info.plist;
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
-				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 11.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = "$(RECOMMENDED_MACOSX_DEPLOYMENT_TARGET)";
 				PRODUCT_BUNDLE_IDENTIFIER = com.scenee.FloatingPanel;
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SKIP_INSTALL = YES;
@@ -521,6 +523,7 @@
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = "$(RECOMMENDED_MACOSX_DEPLOYMENT_TARGET)";
 				PRODUCT_BUNDLE_IDENTIFIER = com.scenee.FloatingPanelTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
@@ -541,6 +544,7 @@
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = "$(RECOMMENDED_MACOSX_DEPLOYMENT_TARGET)";
 				PRODUCT_BUNDLE_IDENTIFIER = com.scenee.FloatingPanelTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;
@@ -627,16 +631,17 @@
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				INFOPLIST_FILE = Sources/Info.plist;
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
-				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 11.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = "$(RECOMMENDED_MACOSX_DEPLOYMENT_TARGET)";
 				PRODUCT_BUNDLE_IDENTIFIER = com.scenee.FloatingPanel;
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SKIP_INSTALL = YES;
-				SWIFT_ACTIVE_COMPILATION_CONDITIONS = "TEST DEBUG __FP_LOG";
+				SWIFT_ACTIVE_COMPILATION_CONDITIONS = "TEST DEBUG FP_LOG";
 				SWIFT_COMPILATION_MODE = singlefile;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 				SWIFT_VERSION = 5.0;
@@ -657,6 +662,7 @@
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
+				MACOSX_DEPLOYMENT_TARGET = "$(RECOMMENDED_MACOSX_DEPLOYMENT_TARGET)";
 				PRODUCT_BUNDLE_IDENTIFIER = com.scenee.FloatingPanelTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_VERSION = 5.0;

Package.swift

@@ -6,7 +6,7 @@ import PackageDescription
 let package = Package(
     name: "FloatingPanel",
     platforms: [
-        .iOS(.v10)
+        .iOS(.v11)
     ],
     products: [
         // Products define the executables and libraries produced by a package, and make them visible to other packages.

README.md

@@ -2,14 +2,13 @@
 [![Platform](https://img.shields.io/cocoapods/p/FloatingPanel.svg)](https://cocoapods.org/pods/FloatingPanel)
 [![Version](https://img.shields.io/cocoapods/v/FloatingPanel.svg)](https://cocoapods.org/pods/FloatingPanel)
 ![GitHub Workflow Status (with branch)](https://img.shields.io/github/actions/workflow/status/scenee/FloatingPanel/ci.yml?branch=master)
-[![Carthage compatible](https://img.shields.io/badge/carthage-compatible-4BC51D.svg?style=flat)](https://github.com/Carthage/Carthage)
 
 # FloatingPanel
 
 FloatingPanel is a simple and easy-to-use UI component designed for a user interface featured in Apple Maps, Shortcuts and Stocks app.
 The user interface displays related content and utilities alongside the main content.
 
-Please see also [the API reference](https://floatingpanel.github.io/2.7.0/documentation/floatingpanel/) for more details.
+Please see also [the API reference@SPI](https://swiftpackageindex.com/scenee/FloatingPanel/2.8.6/documentation/floatingpanel) for more details.
 
 ![Maps](https://github.com/SCENEE/FloatingPanel/blob/master/assets/maps.gif)
 ![Stocks](https://github.com/SCENEE/FloatingPanel/blob/master/assets/stocks.gif)
@@ -21,47 +20,46 @@ Please see also [the API reference](https://floatingpanel.github.io/2.7.0/docume
 - [Features](#features)
 - [Requirements](#requirements)
 - [Installation](#installation)
-    - [CocoaPods](#cocoapods)
-    - [Carthage](#carthage)
-    - [Swift Package Manager](#swift-package-manager)
+  - [CocoaPods](#cocoapods)
+  - [Swift Package Manager](#swift-package-manager)
 - [Getting Started](#getting-started)
-    - [Add a floating panel as a child view controller](#add-a-floating-panel-as-a-child-view-controller)
-    - [Present a floating panel as a modality](#present-a-floating-panel-as-a-modality)
+  - [Add a floating panel as a child view controller](#add-a-floating-panel-as-a-child-view-controller)
+  - [Present a floating panel as a modality](#present-a-floating-panel-as-a-modality)
 - [View hierarchy](#view-hierarchy)
 - [Usage](#usage)
-    - [Show/Hide a floating panel in a view with your view hierarchy](#showhide-a-floating-panel-in-a-view-with-your-view-hierarchy)
-    - [Scale the content view when the surface position changes](#scale-the-content-view-when-the-surface-position-changes)
-    - [Customize the layout with `FloatingPanelLayout` protocol](#customize-the-layout-with-floatingpanellayout-protocol)
-        - [Change the initial layout](#change-the-initial-layout)
-    - [Update your panel layout](#update-your-panel-layout)
-        - [Support your landscape layout](#support-your-landscape-layout)
-        - [Use the intrinsic size of a content in your panel layout](#use-the-intrinsic-size-of-a-content-in-your-panel-layout)
-        - [Specify an anchor for each state by an inset of the `FloatingPanelController.view` frame](#specify-an-anchor-for-each-state-by-an-inset-of-the-floatingpanelcontrollerview-frame)
-        - [Change the backdrop alpha](#change-the-backdrop-alpha)
-        - [Using custome panel states](#using-custome-panel-states)
-    - [Customize the behavior with `FloatingPanelBehavior` protocol](#customize-the-behavior-with-floatingpanelbehavior-protocol)
-        - [Modify your floating panel's interaction](#modify-your-floating-panels-interaction)
-        - [Activate the rubber-band effect on panel edges](#activate-the-rubber-band-effect-on-panel-edges)
-        - [Manage the projection of a pan gesture momentum](#manage-the-projection-of-a-pan-gesture-momentum)
-    - [Specify the panel move's boundary](#specify-the-panel-moves-boundary)
-    - [Customize the surface design](#customize-the-surface-design)
-        - [Modify your surface appearance](#modify-your-surface-appearance)
-        - [Use a custom grabber handle](#use-a-custom-grabber-handle)
-        - [Customize layout of the grabber handle](#customize-layout-of-the-grabber-handle)
-        - [Customize content padding from surface edges](#customize-content-padding-from-surface-edges)
-        - [Customize margins of the surface edges](#customize-margins-of-the-surface-edges)
-    - [Customize gestures](#customize-gestures)
-        - [Suppress the panel interaction](#suppress-the-panel-interaction)
-        - [Add tap gestures to the surface view](#add-tap-gestures-to-the-surface-view)
-        - [Interrupt the delegate methods of `FloatingPanelController.panGestureRecognizer`](#interrupt-the-delegate-methods-of-floatingpanelcontrollerpangesturerecognizer)
-    - [Create an additional floating panel for a detail](#create-an-additional-floating-panel-for-a-detail)
-    - [Move a position with an animation](#move-a-position-with-an-animation)
-    - [Work your contents together with a floating panel behavior](#work-your-contents-together-with-a-floating-panel-behavior)
-    - [Enabling the tap-to-dismiss action of the backdrop view](#enabling-the-tap-to-dismiss-action-of-the-backdrop-view)
+  - [Show/Hide a floating panel in a view with your view hierarchy](#showhide-a-floating-panel-in-a-view-with-your-view-hierarchy)
+  - [Scale the content view when the surface position changes](#scale-the-content-view-when-the-surface-position-changes)
+  - [Customize the layout with `FloatingPanelLayout` protocol](#customize-the-layout-with-floatingpanellayout-protocol)
+    - [Change the initial layout](#change-the-initial-layout)
+  - [Update your panel layout](#update-your-panel-layout)
+    - [Support your landscape layout](#support-your-landscape-layout)
+    - [Use the intrinsic size of a content in your panel layout](#use-the-intrinsic-size-of-a-content-in-your-panel-layout)
+    - [Specify an anchor for each state by an inset of the `FloatingPanelController.view` frame](#specify-an-anchor-for-each-state-by-an-inset-of-the-floatingpanelcontrollerview-frame)
+    - [Change the backdrop alpha](#change-the-backdrop-alpha)
+    - [Using custome panel states](#using-custome-panel-states)
+  - [Customize the behavior with `FloatingPanelBehavior` protocol](#customize-the-behavior-with-floatingpanelbehavior-protocol)
+    - [Modify your floating panel's interaction](#modify-your-floating-panels-interaction)
+    - [Activate the rubber-band effect on panel edges](#activate-the-rubber-band-effect-on-panel-edges)
+    - [Manage the projection of a pan gesture momentum](#manage-the-projection-of-a-pan-gesture-momentum)
+  - [Specify the panel move's boundary](#specify-the-panel-moves-boundary)
+  - [Customize the surface design](#customize-the-surface-design)
+    - [Modify your surface appearance](#modify-your-surface-appearance)
+    - [Use a custom grabber handle](#use-a-custom-grabber-handle)
+    - [Customize layout of the grabber handle](#customize-layout-of-the-grabber-handle)
+    - [Customize content padding from surface edges](#customize-content-padding-from-surface-edges)
+    - [Customize margins of the surface edges](#customize-margins-of-the-surface-edges)
+  - [Customize gestures](#customize-gestures)
+    - [Suppress the panel interaction](#suppress-the-panel-interaction)
+    - [Add tap gestures to the surface view](#add-tap-gestures-to-the-surface-view)
+    - [Interrupt the delegate methods of `FloatingPanelController.panGestureRecognizer`](#interrupt-the-delegate-methods-of-floatingpanelcontrollerpangesturerecognizer)
+  - [Create an additional floating panel for a detail](#create-an-additional-floating-panel-for-a-detail)
+  - [Move a position with an animation](#move-a-position-with-an-animation)
+  - [Work your contents together with a floating panel behavior](#work-your-contents-together-with-a-floating-panel-behavior)
+  - [Enabling the tap-to-dismiss action of the backdrop view](#enabling-the-tap-to-dismiss-action-of-the-backdrop-view)
+  - [Allow to scroll content of the tracking scroll view in addition to the most expanded state](#allow-to-scroll-content-of-the-tracking-scroll-view-in-addition-to-the-most-expanded-state)
 - [Notes](#notes)
-    - ['Show' or 'Show Detail' Segues from `FloatingPanelController`'s content view controller](#show-or-show-detail-segues-from-floatingpanelcontrollers-content-view-controller)
-    - [UISearchController issue](#uisearchcontroller-issue)
-    - [FloatingPanelSurfaceView's issue on iOS 10](#floatingpanelsurfaceviews-issue-on-ios-10)
+  - ['Show' or 'Show Detail' Segues from `FloatingPanelController`'s content view controller](#show-or-show-detail-segues-from-floatingpanelcontrollers-content-view-controller)
+  - [UISearchController issue](#uisearchcontroller-issue)
 - [Maintainer](#maintainer)
 - [License](#license)
 
@@ -93,10 +91,6 @@ Examples can be found here:
 
 FloatingPanel is written in Swift 5.0+ and compatible with iOS 11.0+. 
 
-While it still supports iOS 10, it is recommended to use this library on iOS 11+.
-
-:pencil2: If you'd like to use Swift 4.0, please use FloatingPanel v1.
-
 ## Installation
 
 ### CocoaPods
@@ -108,16 +102,6 @@ it, simply add the following line to your Podfile:
 pod 'FloatingPanel'
 ```
 
-:pencil2: FloatingPanel v1.7.0 or later requires CocoaPods v1.7.0+ for `swift_versions` support.
-
-### Carthage
-
-For [Carthage](https://github.com/Carthage/Carthage), add the following to your `Cartfile`:
-
-```ogdl
-github "scenee/FloatingPanel"
-```
-
 ### Swift Package Manager
 
 Follow [this doc](https://developer.apple.com/documentation/swift_packages/adding_package_dependencies_to_your_app).
@@ -168,7 +152,8 @@ self.present(fpc, animated: true, completion: nil)
 
 You can show a floating panel over UINavigationController from the container view controllers as a modality of `.overCurrentContext` style.
 
-:pencil2: FloatingPanelController has the custom presentation controller. If you would like to customize the presentation/dismissal, please see [Transitioning](https://github.com/SCENEE/FloatingPanel/blob/master/Sources/Transitioning.swift).
+> [!NOTE]
+> FloatingPanelController has the custom presentation controller. If you would like to customize the presentation/dismissal, please see [Transitioning](https://github.com/SCENEE/FloatingPanel/blob/master/Sources/Transitioning.swift).
 
 ## View hierarchy
 
@@ -252,7 +237,8 @@ fpc.contentMode = .fitToBounds
 
 Otherwise, `FloatingPanelController` fixes the content by the height of the top most position.
 
-:pencil2: In `.fitToBounds` mode, the surface height changes as following a user interaction so that you have a responsibility to configure Auto Layout constrains not to break the layout of a content view by the elastic surface height.
+> [!NOTE]
+> In `.fitToBounds` mode, the surface height changes as following a user interaction so that you have a responsibility to configure Auto Layout constrains not to break the layout of a content view by the elastic surface height.
 
 ### Customize the layout with `FloatingPanelLayout` protocol
 
@@ -350,7 +336,8 @@ class IntrinsicPanelLayout: FloatingPanelLayout {
 }
 ```
 
-:pencil2: `FloatingPanelIntrinsicLayout` is deprecated on v1.
+> [!WARNING]
+> `FloatingPanelIntrinsicLayout` is deprecated on v1.
 
 #### Specify an anchor for each state by an inset of the `FloatingPanelController.view` frame
 
@@ -367,7 +354,8 @@ class MyFullScreenLayout: FloatingPanelLayout {
 }
 ```
 
-:pencil2: `FloatingPanelFullScreenLayout` is deprecated on v1.
+> [!WARNING]
+> `FloatingPanelFullScreenLayout` is deprecated on v1.
 
 #### Change the backdrop alpha
 
@@ -431,7 +419,8 @@ class CustomPanelBehavior: FloatingPanelBehavior {
 }
 ```
 
-:pencil2: `floatingPanel(_ vc:behaviorFor:)` is deprecated on v1.
+> [!WARNING]
+> `floatingPanel(_ vc:behaviorFor:)` is deprecated on v1.
 
 #### Activate the rubber-band effect on panel edges
 
@@ -473,7 +462,8 @@ func floatingPanelDidMove(_ vc: FloatingPanelController) {
 }
 ```
 
-:pencil2: `{top,bottom}InteractionBuffer` property is removed from `FloatingPanelLayout` since v2.
+> [!WARNING]
+> `{top,bottom}InteractionBuffer` property is removed from `FloatingPanelLayout` since v2.
 
 ### Customize the surface design
 
@@ -514,7 +504,8 @@ fpc.surfaceView.grabberHandlePadding = 10.0
 fpc.surfaceView.grabberHandleSize = .init(width: 44.0, height: 12.0)
 ```
 
-:pencil2: Note that `grabberHandleSize` width and height are reversed in the left/right position.
+> [!NOTE]
+> `grabberHandleSize` width and height are reversed in the left/right position.
 
 #### Customize content padding from surface edges
 
@@ -663,6 +654,24 @@ The tap-to-dismiss action is disabled by default. So it needs to be enabled as b
 fpc.backdropView.dismissalTapGestureRecognizer.isEnabled = true
 ```
 
+### Allow to scroll content of the tracking scroll view in addition to the most expanded state
+
+Just define conditions to allow content scrolling in `floatingPanel(:_:shouldAllowToScroll:in)` delegate method. If the returned value is true, the scroll content scrolls when its scroll position is not at the top of the content.
+
+```swift
+class MyViewController: FloatingPanelControllerDelegate {
+    ... 
+
+    func floatingPanel(
+        _ fpc: FloatingPanelController,
+        shouldAllowToScroll trackingScrollView: UIScrollView,
+        in state: FloatingPanelState
+    ) -> Bool {
+        return state == .full || state == .half
+    }
+}
+```
+
 ## Notes
 
 ### 'Show' or 'Show Detail' Segues from `FloatingPanelController`'s content view controller
@@ -703,21 +712,6 @@ It's a great way to decouple between a floating panel and the content VC.
 
 Because `UISearchController` automatically presents itself modally when a user interacts with the search bar, and then it swaps the superview of the search bar to the view managed by itself while it displays. As a result, `FloatingPanelController` can't control the search bar when it's active, as you can see from [the screen shot](https://github.com/SCENEE/FloatingPanel/issues/248#issuecomment-521263831).
 
-### FloatingPanelSurfaceView's issue on iOS 10
-
-* On iOS 10, `FloatingPanelSurfaceView.cornerRadius` isn't not automatically masked with the top rounded corners  because of `UIVisualEffectView` issue. See https://forums.developer.apple.com/thread/50854. 
-So you need to draw top rounding corners of your content.  Here is an example in Examples/Maps.
-```swift
-override func viewDidLayoutSubviews() {
-    super.viewDidLayoutSubviews()
-    if #available(iOS 10, *) {
-        visualEffectView.layer.cornerRadius = 9.0
-        visualEffectView.clipsToBounds = true
-    }
-}
-```
-* If you sets clear color to `FloatingPanelSurfaceView.backgroundColor`, please note the bottom overflow of your content on bouncing at full position. To prevent it, you need to expand your content. For example, See Example/Maps App's Auto Layout settings of `UIVisualEffectView` in Main.storyboard.
-
 ## Maintainer
 
 Shin Yamamoto <shin@scenee.com> | [@scenee](https://twitter.com/scenee)

Sources/BackdropView.swift

@@ -4,7 +4,7 @@ import UIKit
 
 /// A view that presents a backdrop interface behind a panel.
 @objc(FloatingPanelBackdropView)
-public class BackdropView: UIView {
+open class BackdropView: UIView {
 
     /// The gesture recognizer for tap gestures to dismiss a panel.
     ///
@@ -12,14 +12,14 @@ public class BackdropView: UIView {
     /// To dismiss a panel by tap gestures on the backdrop, `dismissalTapGestureRecognizer.isEnabled` is set to true.
     @objc public var dismissalTapGestureRecognizer: UITapGestureRecognizer
 
-    init() {
+    public init() {
         dismissalTapGestureRecognizer = UITapGestureRecognizer()
         dismissalTapGestureRecognizer.isEnabled = false
         super.init(frame: .zero)
         addGestureRecognizer(dismissalTapGestureRecognizer)
     }
 
-    required init?(coder: NSCoder) {
+    required public init?(coder: NSCoder) {
         fatalError("init(coder:) has not been implemented")
     }
 }

Sources/Behavior.swift

@@ -25,12 +25,16 @@ public protocol FloatingPanelBehavior {
     @objc optional
     var momentumProjectionRate: CGFloat { get }
 
-    /// Asks the behavior if a panel should project a momentum of a user interaction to move the proposed position.
+    /// Asks the behavior if a panel should project a momentum of a user interaction to move the 
+    /// proposed state.
     ///
-    /// The default implementation of this method returns true. This method is called for a layout to support all positions(tip, half and full).
-    /// Therefore, `proposedState` can only be `FloatingPanelState.tip` or `FloatingPanelState.full`.
+    /// The default implementation of this method returns `false`. This method is called for called
+    /// for all states defined by the current layout object.
     @objc optional
-    func shouldProjectMomentum(_ fpc: FloatingPanelController, to proposedState: FloatingPanelState) -> Bool
+    func shouldProjectMomentum(
+        _ fpc: FloatingPanelController,
+        to proposedState: FloatingPanelState
+    ) -> Bool
 
     /// Returns the progress to redirect to the previous position.
     ///

Sources/Controller.swift

@@ -96,6 +96,35 @@ import os.log
     @objc(floatingPanel:contentOffsetForPinningScrollView:)
     optional
     func floatingPanel(_ fpc: FloatingPanelController, contentOffsetForPinning trackingScrollView: UIScrollView) -> CGPoint
+
+    /// Returns a Boolean value that determines whether the tracking scroll view should
+    /// scroll or not
+    ///
+    ///
+    /// If you return true, the scroll content scrolls when its scroll position is not
+    /// at the top of the content. If the delegate doesn’t implement this method, its
+    /// content can be scrolled only in the most expanded state.
+    ///
+    /// Basically, the decision to scroll is based on the `state` property like the
+    /// following code.
+    /// ```swift
+    /// func floatingPanel(
+    ///     _ fpc: FloatingPanelController,
+    ///     shouldAllowToScroll scrollView: UIScrollView,
+    ///     in state: FloatingPanelState
+    /// ) -> Bool {
+    ///     return state == .full || state == .half
+    /// }
+    /// ```
+    ///
+    /// - Attention: It is recommended that this method always returns the most expanded state(i.e.
+    /// .full). If it excludes the state, the panel might do unexpected behaviors.
+    @objc(floatingPanel:shouldAllowToScroll:in:)
+    optional func floatingPanel(
+        _ fpc: FloatingPanelController,
+        shouldAllowToScroll scrollView: UIScrollView,
+        in state: FloatingPanelState
+    ) -> Bool
 }
 
 ///
@@ -120,7 +149,7 @@ open class FloatingPanelController: UIViewController {
     }
 
     /// The delegate of a panel controller object.
-    @objc 
+    @objc
     public weak var delegate: FloatingPanelControllerDelegate?{
         didSet{
             didUpdateDelegate()
@@ -129,14 +158,15 @@ open class FloatingPanelController: UIViewController {
 
     /// Returns the surface view managed by the controller object. It's the same as `self.view`.
     @objc
-    public var surfaceView: SurfaceView! {
+    public var surfaceView: SurfaceView {
         return floatingPanel.surfaceView
     }
 
     /// Returns the backdrop view managed by the controller object.
     @objc
-    public var backdropView: BackdropView! {
-        return floatingPanel.backdropView
+    public var backdropView: BackdropView {
+        set { floatingPanel.backdropView = newValue }
+        get { return floatingPanel.backdropView }
     }
 
     /// Returns the scroll view that the controller tracks.
@@ -201,7 +231,7 @@ open class FloatingPanelController: UIViewController {
     /// The behavior for determining the adjusted content offsets.
     ///
     /// This property specifies how the content area of the tracking scroll view is modified using ``adjustedContentInsets``. The default value of this property is FloatingPanelController.ContentInsetAdjustmentBehavior.always.
-    @objc 
+    @objc
     public var contentInsetAdjustmentBehavior: ContentInsetAdjustmentBehavior = .always
 
     /// A Boolean value that determines whether the removal interaction is enabled.
@@ -301,19 +331,19 @@ open class FloatingPanelController: UIViewController {
 
     open override func viewDidLayoutSubviews() {
         super.viewDidLayoutSubviews()
-        if #available(iOS 11.0, *) {
-            // Ensure to update the static constraint of a panel after rotating a device in static mode
-            if contentMode == .static {
-                floatingPanel.layoutAdapter.updateStaticConstraint()
-            }
-        } else {
-            // Because {top,bottom}LayoutGuide is managed as a view
-            if floatingPanel.isAttracting == false {
-                self.update(safeAreaInsets: fp_safeAreaInsets)
-            }
+        // Ensure to update the static constraint of a panel after rotating a device in static mode
+        if contentMode == .static {
+            floatingPanel.layoutAdapter.updateStaticConstraint()
         }
     }
 
+    open override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
+        // Need to call this method just after the view appears, as the safe area is not
+        // correctly set before this time, for example, `show(animated:completion:)`.
+        floatingPanel.adjustScrollContentInsetIfNeeded()
+    }
+
     open override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
         super.viewWillTransition(to: size, with: coordinator)
 
@@ -395,6 +425,7 @@ open class FloatingPanelController: UIViewController {
         }
 
         floatingPanel.layoutAdapter.updateStaticConstraint()
+        floatingPanel.adjustScrollContentInsetIfNeeded()
 
         if let contentOffset = contentOffset {
             trackingScrollView?.contentOffset = contentOffset
@@ -445,28 +476,23 @@ open class FloatingPanelController: UIViewController {
         // Must apply the current layout here
         activateLayout(forceLayout: true)
 
-        if #available(iOS 11.0, *) {
-            // Must track the safeAreaInsets of `self.view` to update the layout.
-            // There are 2 reasons.
-            // 1. This or the parent VC doesn't call viewSafeAreaInsetsDidChange() on the bottom
-            // inset's update expectedly.
-            // 2. The safe area top inset can be variable on the large title navigation bar(iOS11+).
-            // That's why it needs the observation to keep `adjustedContentInsets` correct.
-            safeAreaInsetsObservation = self.view.observe(\.safeAreaInsets, options: [.initial, .new, .old]) { [weak self] (_, change) in
-                // Use `self.view.safeAreaInsets` because `change.newValue` can be nil in particular case when
-                // is reported in https://github.com/SCENEE/FloatingPanel/issues/330
-                guard let self = self, change.oldValue != self.view.safeAreaInsets else { return }
+        // Must track the safeAreaInsets of `self.view` to update the layout.
+        // There are 2 reasons.
+        // 1. This or the parent VC doesn't call viewSafeAreaInsetsDidChange() on the bottom
+        // inset's update expectedly.
+        // 2. The safe area top inset can be variable on the large title navigation bar(iOS11+).
+        // That's why it needs the observation to keep `adjustedContentInsets` correct.
+        safeAreaInsetsObservation = self.view.observe(\.safeAreaInsets, options: [.initial, .new, .old]) { [weak self] (_, change) in
+            // Use `self.view.safeAreaInsets` because `change.newValue` can be nil in particular case when
+            // is reported in https://github.com/SCENEE/FloatingPanel/issues/330
+            guard let self = self, change.oldValue != self.view.safeAreaInsets else { return }
 
-                // Sometimes the bounding rectangle of the controlled view becomes invalid when the screen is rotated.
-                // This results in its safeAreaInsets change. In that case, `self.update(safeAreaInsets:)` leads
-                // an unsatisfied constraints error. So this method should not be called with those bounds.
-                guard self.view.bounds.height > 0 && self.view.bounds.width > 0 else { return }
+            // Sometimes the bounding rectangle of the controlled view becomes invalid when the screen is rotated.
+            // This results in its safeAreaInsets change. In that case, `self.update(safeAreaInsets:)` leads
+            // an unsatisfied constraints error. So this method should not be called with those bounds.
+            guard self.view.bounds.height > 0 && self.view.bounds.width > 0 else { return }
 
-                self.update(safeAreaInsets: self.view.safeAreaInsets)
-            }
-        } else {
-            // KVOs for topLayoutGuide & bottomLayoutGuide are not effective.
-            // Instead, update(safeAreaInsets:) is called at `viewDidLayoutSubviews()`
+            self.update(safeAreaInsets: self.view.safeAreaInsets)
         }
 
         move(to: floatingPanel.layoutAdapter.initialState,
@@ -598,18 +624,12 @@ open class FloatingPanelController: UIViewController {
 
         switch contentInsetAdjustmentBehavior {
         case .always:
-            if #available(iOS 11.0, *) {
-                scrollView.contentInsetAdjustmentBehavior = .never
-            } else {
-                children.forEach { (vc) in
-                    vc.automaticallyAdjustsScrollViewInsets = false
-                }
-            }
+            scrollView.contentInsetAdjustmentBehavior = .never
         default:
             break
         }
     }
-    
+
     /// [Experimental] Allows the panel to move as its tracking scroll view bounces.
     ///
     /// This method must be called in the delegate method, `UIScrollViewDelegate.scrollViewDidScroll(_:)`,
@@ -713,6 +733,7 @@ private var originalDismissImp: IMP?
 private typealias DismissFunction = @convention(c) (AnyObject, Selector, Bool, (() -> Void)?) -> Void
 extension FloatingPanelController {
     private static let dismissSwizzling: Void = {
+        guard originalDismissImp == nil else { return }
         let aClass: AnyClass! = UIViewController.self //object_getClass(vc)
         if let originalMethod = class_getInstanceMethod(aClass, #selector(dismiss(animated:completion:))),
            let swizzledImp = class_getMethodImplementation(aClass, #selector(__swizzled_dismiss(animated:completion:))) {

Sources/Core.swift

@@ -10,7 +10,13 @@ class Core: NSObject, UIGestureRecognizerDelegate {
     private weak var ownerVC: FloatingPanelController?
 
     let surfaceView: SurfaceView
-    let backdropView: BackdropView
+    var backdropView: BackdropView {
+        didSet {
+            backdropView.dismissalTapGestureRecognizer
+                .addTarget(self, action: #selector(handleBackdrop(tapGesture:)))
+        }
+    }
+
     let layoutAdapter: LayoutAdapter
     let behaviorAdapter: BehaviorAdapter
 
@@ -24,6 +30,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                     scrollBounce = cur.bounces
                     scrollIndictorVisible = cur.showsVerticalScrollIndicator
                 }
+                scrollLocked = false
             } else {
                 if let pre = oldValue {
                     pre.isDirectionalLockEnabled = false
@@ -37,8 +44,8 @@ class Core: NSObject, UIGestureRecognizerDelegate {
     private(set) var state: FloatingPanelState = .hidden {
         didSet {
             os_log(msg, log: devLog, type: .debug, "state changed: \(oldValue) -> \(state)")
-            if let vc = ownerVC {
-                vc.delegate?.floatingPanelDidChangeState?(vc)
+            if let fpc = ownerVC {
+                fpc.delegate?.floatingPanelDidChangeState?(fpc)
             }
         }
     }
@@ -68,6 +75,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
     private var scrollBounce = false
     private var scrollIndictorVisible = false
     private var scrollBounceThreshold: CGFloat = -30.0
+    private var scrollLocked = false
 
     // MARK: - Interface
 
@@ -120,7 +128,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             completion?()
             return
         }
-        if state != layoutAdapter.mostExpandedState {
+        if !isScrollable(state: state) {
             lockScrollView()
         }
         tearDownActiveInteraction()
@@ -130,7 +138,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         if animated {
             let updateScrollView: () -> Void = { [weak self] in
                 guard let self = self else { return }
-                if self.state == self.layoutAdapter.mostExpandedState, 0 == self.layoutAdapter.offsetFromMostExpandedAnchor {
+                if self.isScrollable(state: self.state), 0 == self.layoutAdapter.offset(from: self.state) {
                     self.unlockScrollView()
                 } else {
                     self.lockScrollView()
@@ -184,7 +192,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         } else {
             self.state = to
             self.updateLayout(to: to)
-            if self.state == self.layoutAdapter.mostExpandedState {
+            if isScrollable(state: state) {
                 self.unlockScrollView()
             } else {
                 self.lockScrollView()
@@ -209,6 +217,9 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             contentOffset = scrollView?.contentOffset
         }
 
+        if layoutAdapter.validStates.contains(state) == false {
+            state = layoutAdapter.initialState
+        }
         layoutAdapter.updateStaticConstraint()
         layoutAdapter.activateLayout(for: state, forceLayout: forceLayout)
 
@@ -221,11 +232,14 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         if let contentOffset = contentOffset {
             scrollView?.contentOffset = contentOffset
         }
+
+        adjustScrollContentInsetIfNeeded()
     }
 
     private func updateLayout(to target: FloatingPanelState) {
-        self.layoutAdapter.activateLayout(for: target, forceLayout: true)
-        self.backdropView.alpha = self.getBackdropAlpha(for: target)
+        layoutAdapter.activateLayout(for: target, forceLayout: true)
+        backdropView.alpha = getBackdropAlpha(for: target)
+        adjustScrollContentInsetIfNeeded()
     }
 
     private func getBackdropAlpha(for target: FloatingPanelState) -> CGFloat {
@@ -294,8 +308,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                 return true
             }
         }
-        if #available(iOS 11.0, *),
-            otherGestureRecognizer.name == "_UISheetInteractionBackgroundDismissRecognizer" {
+        if otherGestureRecognizer.name == "_UISheetInteractionBackgroundDismissRecognizer" {
             // The dismiss gesture of a sheet modal should not begin until the pan gesture fails.
             return true
         }
@@ -327,7 +340,9 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                     if surfaceView.grabberAreaContains(gestureRecognizer.location(in: surfaceView)) {
                         return false
                     }
-                    guard state == layoutAdapter.mostExpandedState else { return false }
+
+                    guard isScrollable(state: state) else { return false }
+
                     // The condition where offset > 0 must not be included here. Because it will stop recognizing
                     // the panel pan gesture if a user starts scrolling content from an offset greater than 0.
                     return allowScrollPanGesture(of: scrollView) { offset in offset <= scrollBounceThreshold  }
@@ -350,8 +365,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
              is UIRotationGestureRecognizer,
              is UIScreenEdgePanGestureRecognizer,
              is UIPinchGestureRecognizer:
-            if #available(iOS 11.0, *),
-                otherGestureRecognizer.name == "_UISheetInteractionBackgroundDismissRecognizer" {
+            if otherGestureRecognizer.name == "_UISheetInteractionBackgroundDismissRecognizer" {
                 // Should begin the pan gesture without waiting the dismiss gesture of a sheet modal.
                 return false
             }
@@ -381,7 +395,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             let velocity = value(of: panGesture.velocity(in: panGesture.view))
             let location = panGesture.location(in: surfaceView)
 
-            let insideMostExpandedAnchor = 0 > layoutAdapter.offsetFromMostExpandedAnchor
+            let insideMostExpandedAnchor = 0 < layoutAdapter.offsetFromMostExpandedAnchor
 
             os_log(msg, log: devLog, type: .debug, """
                 scroll gesture(\(state):\(panGesture.state)) -- \
@@ -392,21 +406,31 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                 """
             )
 
-            let offsetDiff = value(of: scrollView.contentOffset - contentOffsetForPinning(of: scrollView))
+            let baseOffset = contentOffsetForPinning(of: scrollView)
+            let offsetDiff = value(of: scrollView.contentOffset - baseOffset)
 
             if insideMostExpandedAnchor {
-                // Scroll offset pinning
-                if state == layoutAdapter.mostExpandedState {
+                // Prevent scrolling if needed
+                if isScrollable(state: state) {
                     if interactionInProgress {
                         os_log(msg, log: devLog, type: .debug, "settle offset -- \(value(of: initialScrollOffset))")
+                        // Return content offset to initial offset to prevent scrolling
                         stopScrolling(at: initialScrollOffset)
                     } else {
-                        if surfaceView.grabberAreaContains(location) {
+                        if surfaceView.grabberAreaContains(initialLocation) {
                             // Preserve the current content offset in moving from full.
                             stopScrolling(at: initialScrollOffset)
                         }
+                        /// When the scroll offset is at the pinned offset and a panel is moved, the content
+                        /// must be fixed at the pinned position without scrolling. According to the scroll
+                        /// pan gesture behavior, the content might have already scrolled a bit by the time
+                        /// this handler is called. Thus `initialScrollOffset` property is used here.
+                        if value(of: initialScrollOffset - baseOffset) == 0.0 {
+                            stopScrolling(at: initialScrollOffset)
+                        }
                     }
                 } else {
+                    // Return content offset to initial offset to prevent scrolling
                     stopScrolling(at: initialScrollOffset)
                 }
 
@@ -414,7 +438,9 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                 if interactionInProgress {
                     lockScrollView()
                 } else {
-                    if state == layoutAdapter.mostExpandedState, self.transitionAnimator == nil {
+                    // Put back the scroll indicator and bounce of tracking scroll view
+                    // for scrollable states, not most expanded state.
+                    if isScrollable(state: state), self.transitionAnimator == nil {
                         switch layoutAdapter.position {
                         case .top, .left:
                             if offsetDiff < 0 && velocity > 0 {
@@ -428,6 +454,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                     }
                 }
             } else {
+                // Here handles seamless scrolling at the most expanded position
                 if interactionInProgress {
                     // Show a scroll indicator at the top in dragging.
                     switch layoutAdapter.position {
@@ -442,14 +469,14 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                             return
                         }
                     }
-                    if state == layoutAdapter.mostExpandedState {
+                    if isScrollable(state: state) {
                         // Adjust a small gap of the scroll offset just after swiping down starts in the grabber area.
                         if surfaceView.grabberAreaContains(location), surfaceView.grabberAreaContains(initialLocation) {
                             stopScrolling(at: initialScrollOffset)
                         }
                     }
                 } else {
-                    if state == layoutAdapter.mostExpandedState {
+                    if isScrollable(state: state) {
                         let allowScroll = allowScrollPanGesture(of: scrollView) { offset in
                             offset <= scrollBounceThreshold || 0 < offset
                         }
@@ -480,7 +507,9 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             }
         case panGestureRecognizer:
             let translation = panGesture.translation(in: panGestureRecognizer.view!.superview)
+            // The touch velocity in the surface view
             let velocity = panGesture.velocity(in: panGesture.view)
+            // The touch location in the surface view
             let location = panGesture.location(in: panGesture.view)
 
             os_log(msg, log: devLog, type: .debug, """
@@ -538,7 +567,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             endAttraction(false)
         }
         if let animator = self.transitionAnimator {
-            guard 0 >= layoutAdapter.offsetFromMostExpandedAnchor else { return }
+            guard 0 <= layoutAdapter.offsetFromMostExpandedAnchor else { return }
             os_log(msg, log: devLog, type: .debug, "a panel animation(interruptible: \(animator.isInterruptible)) interrupted!!!")
             if animator.isInterruptible {
                 animator.stopAnimation(false)
@@ -557,13 +586,18 @@ class Core: NSObject, UIGestureRecognizerDelegate {
 
     private func shouldScrollViewHandleTouch(_ scrollView: UIScrollView?, point: CGPoint, velocity: CGFloat) -> Bool {
         // When no scrollView, nothing to handle.
-        guard let scrollView = scrollView else { return false }
+        guard let scrollView = scrollView, scrollView.frame.contains(initialLocation) else { return false }
 
-        // For _UISwipeActionPanGestureRecognizer
-        if let scrollGestureRecognizers = scrollView.gestureRecognizers {
+        // Prevents moving a panel on swipe actions using _UISwipeActionPanGestureRecognizer.
+        // [Warning] Do not apply this to WKWebView. Since iOS 17.4, WKWebView has an additional pan
+        // gesture recognizer besides UIScrollViewPanGestureRecognizer. Applying this to WKWebView
+        // will block panel movements because another pan gesture isn't `scrollView.panGestureRecognizer`.
+        if let scrollGestureRecognizers = scrollView.gestureRecognizers,
+            scrollView is UITableView || scrollView is UICollectionView {
             for gesture in scrollGestureRecognizers {
-                guard gesture.state == .began || gesture.state == .changed
-                else { continue }
+                guard gesture.state == .began || gesture.state == .changed else {
+                    continue
+                }
 
                 if gesture != scrollView.panGestureRecognizer {
                     return true
@@ -572,27 +606,10 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         }
 
         guard
-            state == layoutAdapter.mostExpandedState,  // When not top most(i.e. .full), don't scroll.
-            interactionInProgress == false,        // When interaction already in progress, don't scroll.
-            0 == layoutAdapter.offsetFromMostExpandedAnchor
-        else {
-            return false
-        }
-
-        // When the current point is within grabber area but the initial point is not, do scroll.
-        if surfaceView.grabberAreaContains(point), !surfaceView.grabberAreaContains(initialLocation) {
-            return true
-        }
-
-        // When the initial point is within grabber area and the current point is out of surface, don't scroll.
-        if surfaceView.grabberAreaContains(initialLocation), !surfaceView.frame.contains(point) {
-            return false
-        }
-
-        let scrollViewFrame = scrollView.convert(scrollView.bounds, to: surfaceView)
-        guard
-            scrollViewFrame.contains(initialLocation), // When the initial point not in scrollView, don't scroll.
-            !surfaceView.grabberAreaContains(point)        // When point within grabber area, don't scroll.
+            isScrollable(state: state),  // When not top most(i.e. .full), don't scroll.
+            interactionInProgress == false,  // When interaction already in progress, don't scroll.
+            0 == layoutAdapter.offset(from: state),
+            !surfaceView.grabberAreaContains(initialLocation)  // When the initial point is within grabber area, don't scroll
         else {
             return false
         }
@@ -605,14 +622,14 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             if  offset < 0.0 {
                 return true
             }
-            if velocity >= 0 {
+            if velocity >= 0, offset > 0.0 {
                 return true
             }
         case .bottom, .right:
             if  offset > 0.0 {
                 return true
             }
-            if velocity <= 0 {
+            if velocity <= 0, offset < 0.0 {
                 return true
             }
         }
@@ -634,24 +651,24 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         os_log(msg, log: devLog, type: .debug, "panningBegan -- location = \(value(of: location))")
 
         guard let scrollView = scrollView else { return }
-        if state == layoutAdapter.mostExpandedState {
-            if surfaceView.grabberAreaContains(location) {
-                initialScrollOffset = scrollView.contentOffset
-            }
-        } else {
-            initialScrollOffset = scrollView.contentOffset
-        }
+
+        initialScrollOffset = scrollView.contentOffset
     }
 
     private func panningChange(with translation: CGPoint) {
-        os_log(msg, log: devLog, type: .debug, "panningChange -- translation = \(value(of: translation))")
         let pre = value(of: layoutAdapter.surfaceLocation)
         let diff = value(of: translation - initialTranslation)
         let next = pre + diff
 
-        layoutAdapter.updateInteractiveEdgeConstraint(diff: diff,
-                                                      scrollingContent: shouldScrollingContentInMoving(from: pre, to: next),
-                                                      allowsRubberBanding: behaviorAdapter.allowsRubberBanding(for:))
+        os_log(msg, log: devLog, type: .debug, """
+        panningChange -- translation = \(value(of: translation)), diff = \(diff), pre = \(pre), next = \(next)
+        """)
+
+        layoutAdapter.updateInteractiveEdgeConstraint(
+            diff: diff,
+            scrollingContent: shouldScrollingContentInMoving(from: pre, to: next),
+            allowsRubberBanding: behaviorAdapter.allowsRubberBanding(for:)
+        )
 
         let cur = value(of: layoutAdapter.surfaceLocation)
 
@@ -664,31 +681,36 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         }
     }
 
-    private func shouldScrollingContentInMoving(from pre: CGFloat, to next: CGFloat) -> Bool {
+    /// Determines if the content should scroll while the surface is moving from `cur` to `target`.
+    ///
+    /// - Note: `cur` argument starts from an anchor location of surface view in a state. For example,
+    /// it starts from zero if the state is full whose FloatingPanelLayoutAnchor.absoluteInset is zero
+    /// and there is no additional safe area insets like a navigation bar. Therefore, `cur` argument
+    /// can be minus if the absoluteInset is minus with such a condition.
+    private func shouldScrollingContentInMoving(from cur: CGFloat, to target: CGFloat) -> Bool {
         // Don't allow scrolling if the initial panning location is in the grabber area.
         if surfaceView.grabberAreaContains(initialLocation) {
             return false
         }
-        if let scrollView = scrollView, scrollView.panGestureRecognizer.state == .changed {
+        if let sv = scrollView, sv.panGestureRecognizer.state == .changed {
+            let (contentSize, bounds, alwaysBounceHorizontal, alwaysBounceVertical)
+                = (sv.contentSize, sv.bounds, sv.alwaysBounceHorizontal, sv.alwaysBounceVertical)
+
             switch layoutAdapter.position {
             case .top:
-                if pre > .zero, pre < next,
-                    scrollView.contentSize.height > scrollView.bounds.height || scrollView.alwaysBounceVertical {
+                if cur < target, contentSize.height > bounds.height || alwaysBounceVertical {
                     return true
                 }
             case .left:
-                if pre > .zero, pre < next,
-                    scrollView.contentSize.width > scrollView.bounds.width || scrollView.alwaysBounceHorizontal {
+                if cur < target, contentSize.width > bounds.width || alwaysBounceHorizontal {
                     return true
                 }
             case .bottom:
-                if pre > .zero, pre > next,
-                    scrollView.contentSize.height > scrollView.bounds.height || scrollView.alwaysBounceVertical {
+                if cur > target, contentSize.height > bounds.height || alwaysBounceVertical {
                     return true
                 }
             case .right:
-                if pre > .zero, pre > next,
-                    scrollView.contentSize.width > scrollView.bounds.width || scrollView.alwaysBounceHorizontal {
+                if cur > target, contentSize.width > bounds.width || alwaysBounceHorizontal {
                     return true
                 }
             }
@@ -729,14 +751,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         }
 
         guard shouldAttract(to: target) else {
-            self.state = target
-            self.updateLayout(to: target)
-            self.unlockScrollView()
-            // The `floatingPanelDidEndDragging(_:willAttract:)` must be called after the state property changes.
-            // This allows library users to get the correct state in the delegate method.
-            if let vc = ownerVC {
-                vc.delegate?.floatingPanelDidEndDragging?(vc, willAttract: false)
-            }
+            self.endWithoutAttraction(target)
             return
         }
 
@@ -777,13 +792,10 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         var offset: CGPoint = .zero
 
         initialSurfaceLocation = layoutAdapter.surfaceLocation
-        if state == layoutAdapter.mostExpandedState, let scrollView = scrollView {
-            let scrollFrame = scrollView.convert(scrollView.bounds, to: nil)
-            let touchStartingPoint = surfaceView.convert(initialLocation, to: nil)
-
-            ifLabel: if surfaceView.grabberAreaContains(location) {
+        if isScrollable(state: state), let scrollView = scrollView {
+            ifLabel: if surfaceView.grabberAreaContains(initialLocation) {
                 initialScrollOffset = scrollView.contentOffset
-            } else if scrollFrame.contains(touchStartingPoint) {
+            } else if scrollView.frame.contains(initialLocation) {
                 let pinningOffset = contentOffsetForPinning(of: scrollView)
 
                 // This code block handles the scenario where there's a navigation bar or toolbar
@@ -861,7 +873,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         interactionInProgress = false
 
         // Prevent to keep a scroll view indicator visible at the half/tip position
-        if state != layoutAdapter.mostExpandedState {
+        if !isScrollable(state: state) {
             lockScrollView()
         }
 
@@ -882,6 +894,17 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         return true
     }
 
+    func endWithoutAttraction(_ target: FloatingPanelState) {
+        self.state = target
+        self.updateLayout(to: target)
+        self.unlockScrollView()
+        // The `floatingPanelDidEndDragging(_:willAttract:)` must be called after the state property changes.
+        // This allows library users to get the correct state in the delegate method.
+        if let vc = ownerVC {
+            vc.delegate?.floatingPanelDidEndDragging?(vc, willAttract: false)
+        }
+    }
+
     private func startAttraction(to state: FloatingPanelState, with velocity: CGPoint, completion: @escaping (() -> Void)) {
         os_log(msg, log: devLog, type: .debug, "startAnimation to \(state) -- velocity = \(value(of: velocity))")
         guard let vc = ownerVC else { return }
@@ -947,11 +970,11 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         os_log(msg, log: devLog, type: .debug, """
             finishAnimation -- state = \(state) \
             surface location = \(layoutAdapter.surfaceLocation) \
-            edge most position = \(layoutAdapter.surfaceLocation(for: layoutAdapter.mostExpandedState))
+            offset from state position = \(layoutAdapter.offset(from: state))
             """)
 
         if tryUnlockScroll {
-            if (state == layoutAdapter.mostExpandedState && 0 == layoutAdapter.offsetFromMostExpandedAnchor)
+            if (isScrollable(state: state) && 0 == layoutAdapter.offset(from: state))
                 || shouldLooselyLockScrollView {
                 unlockScrollView()
             }
@@ -1042,7 +1065,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             return
         }
         let contentOffset = scrollView.contentOffset.y
-        guard contentOffset < 0, layoutAdapter.position == .bottom, state == layoutAdapter.mostExpandedState else {
+        guard contentOffset < 0, layoutAdapter.position == .bottom, isScrollable(state: state) else {
             if surfaceView.transform != .identity {
                 surfaceView.transform = .identity
                 scrollView.transform = .identity
@@ -1056,14 +1079,11 @@ class Core: NSObject, UIGestureRecognizerDelegate {
     private func lockScrollView(strict: Bool = false) {
         guard let scrollView = scrollView else { return }
 
-        if scrollView.isLocked {
-            os_log(msg, log: devLog, type: .debug, "Already scroll locked.")
+        if scrollLocked {
+            os_log(msg, log: devLog, type: .debug, "Already scroll locked")
             return
         }
-        os_log(msg, log: devLog, type: .debug, "lock scroll view")
-
-        scrollIndictorVisible = scrollView.showsVerticalScrollIndicator
-
+        scrollBounce = scrollView.bounces
         if !strict, shouldLooselyLockScrollView {
             // Don't change its `bounces` property. If it's changed, it will cause its scroll content offset jump at
             // the most expanded anchor position while seamlessly scrolling content. This problem only occurs where its
@@ -1071,26 +1091,49 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             // The reason why is because `bounces` prop change leads to the "content frame" change on `.fitToBounds`.
             // See also https://github.com/scenee/FloatingPanel/issues/524.
         } else {
-            scrollBounce = scrollView.bounces
             scrollView.bounces = false
         }
+        os_log(msg, log: devLog, type: .debug, "lock scroll view")
+
+
+        scrollLocked = true
         scrollView.isDirectionalLockEnabled = true
-        scrollView.showsVerticalScrollIndicator = false
+        switch layoutAdapter.position {
+        case .top, .bottom:
+            scrollIndictorVisible = scrollView.showsVerticalScrollIndicator
+            scrollView.showsVerticalScrollIndicator = false
+        case .left, .right:
+            scrollIndictorVisible = scrollView.showsHorizontalScrollIndicator
+            scrollView.showsHorizontalScrollIndicator = false
+        }
     }
 
     private func unlockScrollView() {
-        guard let scrollView = scrollView, scrollView.isLocked else { return }
+        guard let scrollView = scrollView else { return }
+        if !scrollLocked {
+            os_log(msg, log: devLog, type: .debug, "Already scroll unlocked.")
+            return
+        }
         os_log(msg, log: devLog, type: .debug, "unlock scroll view")
 
+        scrollLocked = false
         scrollView.bounces = scrollBounce
         scrollView.isDirectionalLockEnabled = false
-        scrollView.showsVerticalScrollIndicator = scrollIndictorVisible
+        switch layoutAdapter.position {
+        case .top, .bottom:
+            scrollView.showsVerticalScrollIndicator = scrollIndictorVisible
+        case .left, .right:
+            scrollView.showsHorizontalScrollIndicator = scrollIndictorVisible
+        }
     }
 
     private var shouldLooselyLockScrollView: Bool {
+        if surfaceView.frame == .zero {
+            return false
+        }
         var isSmallScrollContentAndFitToBoundsMode: Bool {
             if ownerVC?.contentMode == .fitToBounds, let scrollView = scrollView,
-               value(of: scrollView.contentSize) < value(of: scrollView.bounds.size) - min(layoutAdapter.offsetFromMostExpandedAnchor, 0) {
+               value(of: scrollView.contentSize) < value(of: scrollView.bounds.size) + max(layoutAdapter.offsetFromMostExpandedAnchor, 0) {
                 return true
             }
             return false
@@ -1116,9 +1159,9 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         case .left:
             return CGPoint(x: scrollView.fp_contentOffsetMax.x, y: 0.0)
         case .bottom:
-            return CGPoint(x: 0.0, y: 0.0 - scrollView.fp_contentInset.top)
+            return CGPoint(x: 0.0, y: 0.0 - scrollView.adjustedContentInset.top)
         case .right:
-            return CGPoint(x: 0.0 - scrollView.fp_contentInset.left, y: 0.0)
+            return CGPoint(x: 0.0 - scrollView.adjustedContentInset.left, y: 0.0)
         }
     }
 
@@ -1132,10 +1175,55 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         }
         return condition(offset)
     }
+
+    func isScrollable(state: FloatingPanelState) -> Bool {
+        guard let scrollView = scrollView else { return false }
+        if let fpc = ownerVC, 
+            let scrollable = fpc.delegate?.floatingPanel?(fpc, shouldAllowToScroll: scrollView, in: state)
+        {
+            return scrollable
+        }
+        return state == layoutAdapter.mostExpandedState
+    }
+
+    /// Adjust content inset of the tracking scroll view if the controller's
+    /// `contentInsetAdjustmentBehavior` is `.always` and its `contentMode` is `.static`.
+    /// if its content is scrollable, the content might not be fully visible on `.half`
+    /// state, for example. Therefore the content inset needs to adjust to display the
+    /// full content.
+    func adjustScrollContentInsetIfNeeded() {
+        guard
+            let fpc = ownerVC,
+            let scrollView = scrollView,
+            fpc.contentInsetAdjustmentBehavior == .always
+        else { return }
+
+        switch fpc.contentMode {
+        case .static:
+            var inset = scrollView.safeAreaInsets
+            let offset = layoutAdapter.offsetFromMostExpandedAnchor
+            if  offset > 0 {
+                switch layoutAdapter.position {
+                case .top:
+                    inset.top = offset + scrollView.safeAreaInsets.top
+                case .bottom:
+                    inset.bottom = offset + scrollView.safeAreaInsets.bottom
+                case .left:
+                    inset.left = offset + scrollView.safeAreaInsets.left
+                case .right:
+                    inset.left = offset + scrollView.safeAreaInsets.right
+                }
+            }
+            scrollView.contentInset = inset
+        case .fitToBounds:
+            scrollView.contentInset = scrollView.safeAreaInsets
+        }
+    }
 }
 
 /// A gesture recognizer that looks for panning (dragging) gestures in a panel.
 public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
+    /// The gesture starting location in the surface view which it is attached to.
     fileprivate var initialLocation: CGPoint = .zero
     private weak var floatingPanel: Core!  //  Core has this gesture recognizer as non-optional
     fileprivate func set(floatingPanel: Core) {
@@ -1144,9 +1232,7 @@ public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
 
     init() {
         super.init(target: nil, action: nil)
-        if #available(iOS 11.0, *) {
-            name = "FloatingPanelPanGestureRecognizer"
-        }
+        name = "FloatingPanelPanGestureRecognizer"
     }
 
     public override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {

Sources/Extensions.swift

@@ -7,7 +7,9 @@ import UIKit
 extension CGFloat {
     /// Returns this value rounded to an logical pixel value by a display scale
     func rounded(by displayScale: CGFloat) -> CGFloat {
-        return (self * displayScale).rounded(.toNearestOrAwayFromZero) / displayScale
+        let p = CGFloat(1.0e9)
+        let v = (self * p).rounded(.towardZero) / p
+        return (v * displayScale).rounded(.toNearestOrAwayFromZero) / displayScale
     }
     func isEqual(to: CGFloat, on displayScale: CGFloat) -> Bool {
         return rounded(by: displayScale) == to.rounded(by: displayScale)
@@ -45,65 +47,16 @@ protocol LayoutGuideProvider {
 extension UILayoutGuide: LayoutGuideProvider {}
 extension UIView: LayoutGuideProvider {}
 
-private class CustomLayoutGuide: LayoutGuideProvider {
-    let topAnchor: NSLayoutYAxisAnchor
-    let leftAnchor: NSLayoutXAxisAnchor
-    let bottomAnchor: NSLayoutYAxisAnchor
-    let rightAnchor: NSLayoutXAxisAnchor
-    let widthAnchor: NSLayoutDimension
-    let heightAnchor: NSLayoutDimension
-    init(topAnchor: NSLayoutYAxisAnchor,
-         leftAnchor: NSLayoutXAxisAnchor,
-         bottomAnchor: NSLayoutYAxisAnchor,
-         rightAnchor: NSLayoutXAxisAnchor,
-         widthAnchor: NSLayoutDimension,
-         heightAnchor: NSLayoutDimension) {
-        self.topAnchor = topAnchor
-        self.leftAnchor = leftAnchor
-        self.bottomAnchor = bottomAnchor
-        self.rightAnchor = rightAnchor
-        self.widthAnchor = widthAnchor
-        self.heightAnchor = heightAnchor
-    }
-}
-
 extension UIViewController {
+    /// The proxy property to be used in `LayoutAdapter`
+    ///
+    /// This property is to allow the safe area inset to change in unit testing
     @objc var fp_safeAreaInsets: UIEdgeInsets {
-        if #available(iOS 11.0, *) {
-            return view.safeAreaInsets
-        } else {
-            return UIEdgeInsets(top: topLayoutGuide.length,
-                                left: 0.0,
-                                bottom: bottomLayoutGuide.length,
-                                right: 0.0)
-        }
-    }
-
-    var fp_safeAreaLayoutGuide: LayoutGuideProvider {
-        if #available(iOS 11.0, *) {
-            return view!.safeAreaLayoutGuide
-        } else {
-            return CustomLayoutGuide(topAnchor: topLayoutGuide.bottomAnchor,
-                                     leftAnchor: view.leftAnchor,
-                                     bottomAnchor: bottomLayoutGuide.topAnchor,
-                                     rightAnchor: view.rightAnchor,
-                                     widthAnchor: view.widthAnchor,
-                                     heightAnchor: topLayoutGuide.bottomAnchor.anchorWithOffset(to: bottomLayoutGuide.topAnchor))
-        }
+        return view.safeAreaInsets
     }
 }
 
-// The reason why UIView has no extensions of safe area insets and top/bottom guides
-// is for iOS10 compatibility.
 extension UIView {
-    var fp_safeAreaLayoutGuide: LayoutGuideProvider {
-        if #available(iOS 11.0, *) {
-            return safeAreaLayoutGuide
-        } else {
-            return self
-        }
-    }
-
     var presentationFrame: CGRect {
         return layer.presentation()?.frame ?? frame
     }
@@ -139,7 +92,7 @@ extension UIView {
     }
 }
 
-#if __FP_LOG
+#if FP_LOG
 extension UIGestureRecognizer.State: CustomDebugStringConvertible {
     public var debugDescription: String {
         switch self {
@@ -156,19 +109,9 @@ extension UIGestureRecognizer.State: CustomDebugStringConvertible {
 #endif
 
 extension UIScrollView {
-    var isLocked: Bool {
-        return !showsVerticalScrollIndicator && !bounces &&  isDirectionalLockEnabled
-    }
-    var fp_contentInset: UIEdgeInsets {
-        if #available(iOS 11.0, *) {
-            return adjustedContentInset
-        } else {
-            return contentInset
-        }
-    }
     var fp_contentOffsetMax: CGPoint {
-        return CGPoint(x: max((contentSize.width + fp_contentInset.right) - bounds.width, 0.0),
-                       y: max((contentSize.height + fp_contentInset.bottom) - bounds.height, 0.0))
+        return CGPoint(x: max((contentSize.width + adjustedContentInset.right) - bounds.width, 0.0),
+                       y: max((contentSize.height + adjustedContentInset.bottom) - bounds.height, 0.0))
     }
 }
 

Sources/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.7.0</string>
+	<string>2.8.6</string>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
 </dict>

Sources/Layout.swift

@@ -45,8 +45,8 @@ open class FloatingPanelBottomLayout: NSObject, FloatingPanelLayout {
 
     open func prepareLayout(surfaceView: UIView, in view: UIView) -> [NSLayoutConstraint] {
         return [
-            surfaceView.leftAnchor.constraint(equalTo: view.fp_safeAreaLayoutGuide.leftAnchor, constant: 0.0),
-            surfaceView.rightAnchor.constraint(equalTo: view.fp_safeAreaLayoutGuide.rightAnchor, constant: 0.0),
+            surfaceView.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor, constant: 0.0),
+            surfaceView.rightAnchor.constraint(equalTo: view.safeAreaLayoutGuide.rightAnchor, constant: 0.0),
         ]
     }
 
@@ -266,12 +266,23 @@ class LayoutAdapter {
     }
 
     var offsetFromMostExpandedAnchor: CGFloat {
+        return offset(from: mostExpandedState)
+    }
+
+    /// The distance from the given state position to the current surface location.
+    ///
+    /// If the returned value is positive, it indicates that the surface is moving from
+    /// the given state position to closer to the `hidden` state position. In other
+    /// words, the surface is within the given state position. Otherwise, it indicates
+    /// that the surface is outside this position and is moving away from the `hidden`
+    /// state position.
+    func offset(from state: FloatingPanelState) -> CGFloat {
         let offset: CGFloat
         switch position {
         case .top, .left:
-            offset = edgePosition(surfaceView.presentationFrame) - position(for: mostExpandedState)
+            offset = position(for: state) - edgePosition(surfaceView.frame)
         case .bottom, .right:
-            offset = position(for: mostExpandedState) - edgePosition(surfaceView.presentationFrame)
+            offset = edgePosition(surfaceView.frame) - position(for: state)
         }
         return offset.rounded(by: surfaceView.fp_displayScale)
     }
@@ -424,13 +435,13 @@ class LayoutAdapter {
             switch position {
             case .top, .bottom:
                 surfaceConstraints = [
-                    surfaceView.leftAnchor.constraint(equalTo: vc.fp_safeAreaLayoutGuide.leftAnchor, constant: 0.0),
-                    surfaceView.rightAnchor.constraint(equalTo: vc.fp_safeAreaLayoutGuide.rightAnchor, constant: 0.0),
+                    surfaceView.leftAnchor.constraint(equalTo: vc.view.safeAreaLayoutGuide.leftAnchor, constant: 0.0),
+                    surfaceView.rightAnchor.constraint(equalTo: vc.view.safeAreaLayoutGuide.rightAnchor, constant: 0.0),
                 ]
             case .left, .right:
                 surfaceConstraints = [
-                    surfaceView.topAnchor.constraint(equalTo: vc.fp_safeAreaLayoutGuide.topAnchor, constant: 0.0),
-                    surfaceView.bottomAnchor.constraint(equalTo: vc.fp_safeAreaLayoutGuide.bottomAnchor, constant: 0.0),
+                    surfaceView.topAnchor.constraint(equalTo: vc.view.safeAreaLayoutGuide.topAnchor, constant: 0.0),
+                    surfaceView.bottomAnchor.constraint(equalTo: vc.view.safeAreaLayoutGuide.bottomAnchor, constant: 0.0),
                 ]
             }
         }
@@ -538,7 +549,7 @@ class LayoutAdapter {
         let layoutGuideProvider: LayoutGuideProvider
         switch anchor.referenceGuide {
         case .safeArea:
-            layoutGuideProvider = vc.fp_safeAreaLayoutGuide
+            layoutGuideProvider = vc.view.safeAreaLayoutGuide
         case .superview:
             layoutGuideProvider = vc.view
         }
@@ -771,12 +782,6 @@ class LayoutAdapter {
             NSLayoutConstraint.activate(constraint: self.fitToBoundsConstraint)
         }
 
-        var state = state
-
-        if validStates.contains(state) == false {
-            state = layout.initialState
-        }
-
         // Recalculate the intrinsic size of a content view. This is because
         // UIView.systemLayoutSizeFitting() returns a different size between an
         // on-screen and off-screen view which includes

Sources/LayoutAnchoring.swift

@@ -17,7 +17,7 @@ import UIKit
     /// positioning.
     ///
     /// - Parameters:
-    ///     - absoluteOffset: An absolute offset to attach the panel from the edge.
+    ///     - absoluteInset: An absolute distance to attach the panel from the specified edge.
     ///     - edge: Specify the edge of ``FloatingPanelController``'s view. This is the staring point of the offset.
     ///     - referenceGuide: The rectangular area to lay out the content. If it's set to `.safeArea`, the panel content lays out inside the safe area of its ``FloatingPanelController``'s view.
     @objc public init(absoluteInset: CGFloat, edge: FloatingPanelReferenceEdge, referenceGuide: FloatingPanelLayoutReferenceGuide) {
@@ -34,7 +34,7 @@ import UIKit
     /// 1.0 represents a distance to the opposite edge.
     ///
     /// - Parameters:
-    ///     - fractionalOffset: A fractional value of the size of ``FloatingPanelController``'s view to attach the panel from the edge.
+    ///     - fractionalInset: A fractional value of the size of ``FloatingPanelController``'s view to attach the panel from the specified edge.
     ///     - edge: Specify the edge of ``FloatingPanelController``'s view. This is the staring point of the offset.
     ///     - referenceGuide: The rectangular area to lay out the content. If it's set to `.safeArea`, the panel content lays out inside the safe area of its ``FloatingPanelController``'s view.
     @objc public init(fractionalInset: CGFloat, edge: FloatingPanelReferenceEdge, referenceGuide: FloatingPanelLayoutReferenceGuide) {
@@ -115,8 +115,8 @@ public extension FloatingPanelLayoutAnchor {
     /// - Parameters:
     ///     - absoluteOffset: An absolute offset from the content size in the main dimension(i.e. y axis for a bottom panel) to attach the panel.
     ///     - referenceGuide: The rectangular area to lay out the content. If it's set to `.safeArea`, the panel content lays out inside the safe area of its ``FloatingPanelController``'s view.
-    @objc public init(absoluteOffset offset: CGFloat, referenceGuide: FloatingPanelLayoutReferenceGuide = .safeArea) {
-        self.offset = offset
+    @objc public init(absoluteOffset: CGFloat, referenceGuide: FloatingPanelLayoutReferenceGuide = .safeArea) {
+        self.offset = absoluteOffset
         self.referenceGuide = referenceGuide
         self.isAbsolute = true
     }
@@ -129,8 +129,8 @@ public extension FloatingPanelLayoutAnchor {
     /// - Parameters:
     ///     - fractionalOffset: A fractional offset of the content size in the main dimension(i.e. y axis for a bottom panel) to attach the panel.
     ///     - referenceGuide: The rectangular area to lay out the content. If it's set to `.safeArea`, the panel content lays out inside the safe area of its ``FloatingPanelController``'s view.
-    @objc public init(fractionalOffset offset: CGFloat, referenceGuide: FloatingPanelLayoutReferenceGuide = .safeArea) {
-        self.offset = offset
+    @objc public init(fractionalOffset: CGFloat, referenceGuide: FloatingPanelLayoutReferenceGuide = .safeArea) {
+        self.offset = fractionalOffset
         self.referenceGuide = referenceGuide
         self.isAbsolute = false
     }
@@ -177,12 +177,12 @@ public extension FloatingPanelIntrinsicLayoutAnchor {
     ///
     /// - Warning: If ``contentBoundingGuide`` is set to none, the panel may expand out of the screen size, depending on the intrinsic size of its content.
     @objc public init(
-        absoluteOffset offset: CGFloat,
+        absoluteOffset: CGFloat,
         contentLayout: UILayoutGuide,
         referenceGuide: FloatingPanelLayoutReferenceGuide,
         contentBoundingGuide: FloatingPanelLayoutContentBoundingGuide = .none
     ) {
-        self.offset = offset
+        self.offset = absoluteOffset
         self.contentLayoutGuide = contentLayout
         self.referenceGuide = referenceGuide
         self.contentBoundingGuide = contentBoundingGuide
@@ -204,12 +204,12 @@ public extension FloatingPanelIntrinsicLayoutAnchor {
     ///
     /// - Warning: If ``contentBoundingGuide`` is set to none, the panel may expand out of the screen size, depending on the intrinsic size of its content.
     @objc public init(
-        fractionalOffset offset: CGFloat,
+        fractionalOffset: CGFloat,
         contentLayout: UILayoutGuide,
         referenceGuide: FloatingPanelLayoutReferenceGuide,
         contentBoundingGuide: FloatingPanelLayoutContentBoundingGuide = .none
     ) {
-        self.offset = offset
+        self.offset = fractionalOffset
         self.contentLayoutGuide = contentLayout
         self.referenceGuide = referenceGuide
         self.contentBoundingGuide = contentBoundingGuide

Sources/LayoutProperties.swift

@@ -37,7 +37,7 @@ extension FloatingPanelLayoutReferenceGuide {
     func layoutGuide(vc: UIViewController) -> LayoutGuideProvider {
         switch self {
         case .safeArea:
-            return vc.fp_safeAreaLayoutGuide
+            return vc.view.safeAreaLayoutGuide
         case .superview:
             return vc.view
         }
@@ -57,7 +57,7 @@ extension FloatingPanelLayoutContentBoundingGuide {
         case .superview:
             return fpc.view
         case .safeArea:
-            return fpc.fp_safeAreaLayoutGuide
+            return fpc.view.safeAreaLayoutGuide
         case .none:
             return nil
         }

Sources/SurfaceView.swift

@@ -56,11 +56,11 @@ public class SurfaceAppearance: NSObject {
     /// Defaults to `.circular`.
     @available(iOS 13.0, *)
     public var cornerCurve: CALayerCornerCurve {
-        get { _cornerCurve ?? .circular }
+        get { _cornerCurve as? CALayerCornerCurve ?? .circular }
         set { _cornerCurve = newValue }
     }
 
-    private var _cornerCurve: CALayerCornerCurve?
+    private var _cornerCurve: Any?
 
     /// An array of shadows used to create drop shadows underneath a surface view.
     public var shadows: [Shadow] = [Shadow()]
@@ -383,29 +383,24 @@ public class SurfaceView: UIView {
         }
         containerView.layer.masksToBounds = true
         if position.inset(containerMargins) != 0 {
-            if #available(iOS 11, *) {
-                containerView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner,
-                                                     .layerMinXMaxYCorner, .layerMaxXMaxYCorner]
-            }
+            containerView.layer.maskedCorners = [
+                .layerMinXMinYCorner, .layerMaxXMinYCorner,
+                .layerMinXMaxYCorner, .layerMaxXMaxYCorner
+            ]
             return
         }
-        if #available(iOS 11, *) {
-            // Don't use `contentView.clipToBounds` because it prevents content view from expanding the height of a subview of it
-            // for the bottom overflow like Auto Layout settings of UIVisualEffectView in Main.storyboard of Example/Maps.
-            // Because the bottom of contentView must be fit to the bottom of a screen to work the `safeLayoutGuide` of a content VC.
-            switch position {
-            case .top:
-                containerView.layer.maskedCorners = [.layerMinXMaxYCorner, .layerMaxXMaxYCorner]
-            case .left:
-                containerView.layer.maskedCorners = [.layerMaxXMinYCorner, .layerMaxXMaxYCorner]
-            case .bottom:
-                containerView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
-            case .right:
-                containerView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMinXMaxYCorner]
-            }
-        } else {
-            // Can't use `containerView.layer.mask` because of a UIVisualEffectView issue in iOS 10, https://forums.developer.apple.com/thread/50854
-            // Instead, a user should display rounding corners appropriately.
+        // Don't use `contentView.clipToBounds` because it prevents content view from expanding the height of a subview of it
+        // for the bottom overflow like Auto Layout settings of UIVisualEffectView in Main.storyboard of Example/Maps.
+        // Because the bottom of contentView must be fit to the bottom of a screen to work the `safeLayoutGuide` of a content VC.
+        switch position {
+        case .top:
+            containerView.layer.maskedCorners = [.layerMinXMaxYCorner, .layerMaxXMaxYCorner]
+        case .left:
+            containerView.layer.maskedCorners = [.layerMaxXMinYCorner, .layerMaxXMaxYCorner]
+        case .bottom:
+            containerView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
+        case .right:
+            containerView.layer.maskedCorners = [.layerMinXMinYCorner, .layerMinXMaxYCorner]
         }
     }
 
@@ -423,12 +418,30 @@ public class SurfaceView: UIView {
         let leftConstraint = contentView.leftAnchor.constraint(equalTo: leftAnchor, constant: containerMargins.left + contentPadding.left)
         let rightConstraint = rightAnchor.constraint(equalTo: contentView.rightAnchor, constant: containerMargins.right + contentPadding.right)
         let bottomConstraint = bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: containerMargins.bottom + contentPadding.bottom)
-        NSLayoutConstraint.activate([
+
+        var constraints = [
             topConstraint,
             leftConstraint,
             rightConstraint,
-            bottomConstraint,
-        ].map {
+            bottomConstraint
+        ]
+
+        // This constraint is for UICollectionView using UICollectionViewCompositionalLayout.
+        // It's seemingly obvious, but the UICollectionView doesn't work without setting it. (#628)
+        switch position {
+        case .top, .bottom:
+            constraints += [
+                heightAnchor.constraint(greaterThanOrEqualToConstant: 1.0)
+            ]
+        case .left, .right:
+            constraints += [
+                widthAnchor.constraint(greaterThanOrEqualToConstant: 1.0)
+            ]
+        }
+
+        NSLayoutConstraint.activate(
+            constraints
+            .map {
             switch mode {
             case .static:
                 $0.priority = .required

Sources/Transitioning.swift

@@ -84,7 +84,7 @@ class ModalPresentTransition: NSObject, UIViewControllerAnimatedTransitioning {
     func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
         guard
             let fpc = transitionContext?.viewController(forKey: .to) as? FloatingPanelController
-        else { fatalError()}
+        else { return 0.0 }
 
         let animator = fpc.animatorForPresenting(to: fpc.layout.initialState)
         return TimeInterval(animator.duration)
@@ -119,7 +119,7 @@ class ModalDismissTransition: NSObject, UIViewControllerAnimatedTransitioning {
     func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
         guard
             let fpc = transitionContext?.viewController(forKey: .from) as? FloatingPanelController
-        else { fatalError()}
+        else { return 0.0 }
 
         let animator = fpc.animatorForDismissing(with: .zero)
         return TimeInterval(animator.duration)

Tests/ControllerTests.swift

@@ -64,6 +64,7 @@ class ControllerTests: XCTestCase {
     }
 
     func test_moveTo() {
+        let timeout = 3.0
         let delegate = FloatingPanelTestDelegate()
         let fpc = FloatingPanelController(delegate: delegate)
         XCTAssertEqual(delegate.position, .hidden)
@@ -102,7 +103,7 @@ class ControllerTests: XCTestCase {
             }
             XCTAssertEqual(fpc.state, .full)
             XCTAssertEqual(delegate.position, .full)
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
         }
 
         XCTContext.runActivity(named: "move to half(animated)") { act in
@@ -113,7 +114,7 @@ class ControllerTests: XCTestCase {
             }
             XCTAssertEqual(fpc.state, .half)
             XCTAssertEqual(delegate.position, .half)
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
         }
 
         XCTContext.runActivity(named: "move to tip(animated)") { act in
@@ -124,7 +125,7 @@ class ControllerTests: XCTestCase {
             }
             XCTAssertEqual(fpc.state, .tip)
             XCTAssertEqual(delegate.position, .tip)
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
         }
 
         fpc.move(to: .hidden, animated: true)
@@ -137,6 +138,7 @@ class ControllerTests: XCTestCase {
         class MyFloatingPanelTop2BottomLayout: FloatingPanelTop2BottomTestLayout {
             override var initialState: FloatingPanelState { return .half }
         }
+        let timeout = 3.0
         let delegate = FloatingPanelTestDelegate()
         let fpc = FloatingPanelController(delegate: delegate)
         fpc.layout = MyFloatingPanelTop2BottomLayout()
@@ -175,7 +177,7 @@ class ControllerTests: XCTestCase {
             }
             XCTAssertEqual(fpc.state, .full)
             XCTAssertEqual(delegate.position, .full)
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
         }
 
         XCTContext.runActivity(named: "move to half(animated)") { act in
@@ -186,7 +188,7 @@ class ControllerTests: XCTestCase {
             }
             XCTAssertEqual(fpc.state, .half)
             XCTAssertEqual(delegate.position, .half)
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
         }
 
         XCTContext.runActivity(named: "move to tip(animated)") { act in
@@ -197,7 +199,7 @@ class ControllerTests: XCTestCase {
             }
             XCTAssertEqual(fpc.state, .tip)
             XCTAssertEqual(delegate.position, .tip)
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
         }
 
         fpc.move(to: .hidden, animated: true)
@@ -223,6 +225,7 @@ class ControllerTests: XCTestCase {
     }
 
     func test_moveTo_didMoveDelegate() {
+        let timeout = 3.0
         let delegate = FloatingPanelTestDelegate()
         let fpc = FloatingPanelController(delegate: delegate)
         XCTAssertEqual(delegate.position, .hidden)
@@ -237,7 +240,7 @@ class ControllerTests: XCTestCase {
                 exp.fulfill()
             }
             fpc.move(to: .full, animated: false)
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
 
             XCTAssertEqual(count, 1)
         }
@@ -253,7 +256,7 @@ class ControllerTests: XCTestCase {
             fpc.move(to: .half, animated: true) {
                 exp.fulfill()
             }
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
 
             XCTAssertGreaterThan(count, 1)
         }
@@ -270,7 +273,7 @@ class ControllerTests: XCTestCase {
                     exp.fulfill()
                 }
             }
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
 
             XCTAssertEqual(count, 1)
         }
@@ -288,7 +291,7 @@ class ControllerTests: XCTestCase {
                     exp.fulfill()
                 }
             }
-            wait(for: [exp], timeout: 1.0)
+            wait(for: [exp], timeout: timeout)
 
             XCTAssertGreaterThan(count, 1)
         }
@@ -334,6 +337,36 @@ class ControllerTests: XCTestCase {
         fpc.move(to: .tip, animated: false)
         XCTAssertEqual(fpc.surfaceView.frame.height, fpc.view.bounds.height - fpc.surfaceLocation(for: .tip).y)
     }
+
+    func test_switching_layout() {
+        final class FirstLayout: FloatingPanelLayout {
+            let position: FloatingPanelPosition = .bottom
+            let initialState: FloatingPanelState = .half
+            let anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] = [
+                .full: FloatingPanelLayoutAnchor(absoluteInset: 16.0, edge: .top, referenceGuide: .safeArea),
+                .half: FloatingPanelLayoutAnchor(absoluteInset: 262, edge: .top, referenceGuide: .safeArea),
+                .tip: FloatingPanelLayoutAnchor(absoluteInset: 44.0, edge: .bottom, referenceGuide: .safeArea)
+            ]
+        }
+        final class SecondLayout: FloatingPanelLayout {
+            let position: FloatingPanelPosition = .bottom
+            let initialState: FloatingPanelState = .half
+            let anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] = [
+                .half: FloatingPanelLayoutAnchor(absoluteInset: 262, edge: .top, referenceGuide: .safeArea)
+            ]
+        }
+        let fpc = FloatingPanelController()
+        fpc.layout = FirstLayout()
+        fpc.showForTest()
+
+        fpc.move(to: .tip, animated: false)
+
+        // Switch to another layout
+        fpc.layout = SecondLayout()
+        fpc.invalidateLayout()
+
+        XCTAssertEqual(fpc.state, .half)
+    }
 }
 
 private class MyZombieViewController: UIViewController, FloatingPanelLayout, FloatingPanelBehavior, FloatingPanelControllerDelegate {

Tests/CoreTests.swift

@@ -209,6 +209,8 @@ class CoreTests: XCTestCase {
             return floor(fpc.backdropView.alpha * 1e+06) / 1e+06
         }
 
+        let timeout = 3.0
+
         let delegate = TestDelegate()
         let fpc = FloatingPanelController(delegate: delegate)
         fpc.layout = BackdropTestLayout()
@@ -228,14 +230,14 @@ class CoreTests: XCTestCase {
         fpc.move(to: .full, animated: true) {
             exp1.fulfill()
         }
-        wait(for: [exp1], timeout: 1.0)
+        wait(for: [exp1], timeout: timeout)
         XCTAssertEqual(_floor(fpc.backdropView.alpha), 0.3)
 
         let exp2 = expectation(description: "move to half with animation")
         fpc.move(to: .half, animated: true) {
             exp2.fulfill()
         }
-        wait(for: [exp2], timeout: 1.0)
+        wait(for: [exp2], timeout: timeout)
         XCTAssertEqual(fpc.backdropView.alpha, 0.0)
 
         // Test a content mode change of FloatingPanelController
@@ -246,7 +248,7 @@ class CoreTests: XCTestCase {
         }
         fpc.contentMode = .fitToBounds
         XCTAssertEqual(fpc.backdropView.alpha, 0.0)  // Must not affect the backdrop alpha by changing the content mode
-        wait(for: [exp3], timeout: 1.0)
+        wait(for: [exp3], timeout: timeout)
         XCTAssertEqual(_floor(fpc.backdropView.alpha), 0.3)
 
         // Test a size class change of FloatingPanelController.view
@@ -820,6 +822,119 @@ class CoreTests: XCTestCase {
         fpc.showForTest()
         XCTAssertFalse(fpc.panGestureRecognizer.isEnabled)
     }
+
+    func test_is_scrollable() {
+        class Delegate: FloatingPanelControllerDelegate {
+            var shouldScroll = false
+            func floatingPanel(
+                _ fpc: FloatingPanelController,
+                shouldAllowToScroll scrollView: UIScrollView,
+                in state: FloatingPanelState
+            ) -> Bool {
+                return shouldScroll
+            }
+        }
+
+        let fpc = FloatingPanelController()
+        let scrollView = UIScrollView()
+        let delegate = Delegate()
+        fpc.layout = FloatingPanelBottomLayout()
+        fpc.track(scrollView: scrollView)
+        fpc.showForTest()
+
+        XCTAssertTrue(fpc.floatingPanel.isScrollable(state: .full))
+        XCTAssertFalse(fpc.floatingPanel.isScrollable(state: .half))
+
+        fpc.delegate = delegate
+
+        XCTAssertFalse(fpc.floatingPanel.isScrollable(state: .full))
+        XCTAssertFalse(fpc.floatingPanel.isScrollable(state: .half))
+
+        delegate.shouldScroll = true
+
+        XCTAssertTrue(fpc.floatingPanel.isScrollable(state: .full))
+        XCTAssertTrue(fpc.floatingPanel.isScrollable(state: .half))
+    }
+
+    func test_adjustScrollContentInsetIfNeeded() {
+        class CustomScrollView: UIScrollView {
+            var customSafeAreaInsets: UIEdgeInsets = .zero
+            override var safeAreaInsets: UIEdgeInsets {
+                customSafeAreaInsets
+            }
+        }
+
+        do {
+            let scrollView = CustomScrollView()
+            scrollView.customSafeAreaInsets = UIEdgeInsets(top: 0, left: 0, bottom: 34, right: 0)
+            let fpc = FloatingPanelController()
+            fpc.track(scrollView: scrollView)
+            fpc.layout = FloatingPanelBottomLayout()
+            fpc.contentInsetAdjustmentBehavior = .always
+            fpc.contentMode = .static
+            fpc.showForTest()
+
+            fpc.move(to: .half, animated: false)
+            fpc.floatingPanel.adjustScrollContentInsetIfNeeded()
+
+            let expect = 34 + (fpc.surfaceLocation(for: .half).y - fpc.surfaceLocation(for: .full).y)
+            XCTAssertEqual(
+                scrollView.contentInset,
+                UIEdgeInsets(top: 0, left: 0, bottom: expect, right: 0)
+            )
+
+            fpc.contentMode = .fitToBounds
+            XCTAssertEqual(
+                scrollView.contentInset,
+                scrollView.customSafeAreaInsets
+            )
+        }
+
+        do {
+            let scrollView = CustomScrollView()
+            scrollView.customSafeAreaInsets = UIEdgeInsets(top: 91, left: 0, bottom: 0, right: 0)
+            let fpc = FloatingPanelController()
+            fpc.track(scrollView: scrollView)
+            fpc.layout = FloatingPanelTopPositionedLayout()
+            fpc.contentInsetAdjustmentBehavior = .always
+            fpc.contentMode = .static
+            fpc.showForTest()
+
+            fpc.move(to: .half, animated: false)
+            fpc.floatingPanel.adjustScrollContentInsetIfNeeded()
+
+            let expect = 91 + (fpc.surfaceLocation(for: .full).y -  fpc.surfaceLocation(for: .half).y)
+            XCTAssertEqual(
+                scrollView.contentInset,
+                UIEdgeInsets(top: expect, left: 0, bottom: 0, right: 0)
+            )
+            fpc.contentMode = .fitToBounds
+            XCTAssertEqual(
+                scrollView.contentInset,
+                scrollView.customSafeAreaInsets
+            )
+        }
+    }
+
+    func test_handleGesture_endWithoutAttraction() throws {
+        class Delegate: FloatingPanelControllerDelegate {
+            var willAttract: Bool?
+            func floatingPanelDidEndDragging(_ fpc: FloatingPanelController, willAttract attract: Bool) {
+                willAttract = attract
+            }
+        }
+        let fpc = FloatingPanelController()
+        let delegate = Delegate()
+        fpc.showForTest()
+        fpc.delegate = delegate
+        XCTAssertEqual(fpc.state, .half)
+
+        fpc.floatingPanel.endWithoutAttraction(.full)
+
+        XCTAssertEqual(fpc.state, .full)
+        XCTAssertEqual(fpc.surfaceLocation(for: .full).y, fpc.surfaceLocation.y)
+        XCTAssertEqual(delegate.willAttract, false)
+    }
 }
 
 private class FloatingPanelLayout3Positions: FloatingPanelTestLayout {

Tests/ExtensionTests.swift

@@ -9,4 +9,20 @@ class ExtensionTests: XCTestCase {
         XCTAssertNotEqual(CGFloat(333.5).rounded(by: 3), 333.66666666666674)
         XCTAssertTrue(CGFloat(333.5).isEqual(to: 333.66666666666674, on: 3.0))
     }
+    
+    func test_roundedByDisplayScale_2() {
+        XCTAssertEqual(CGFloat(-0.16666666666674246).rounded(by: 3), 0.0)
+        XCTAssertEqual(CGFloat(0.16666666666674246).rounded(by: 3), 0.0)
+
+        XCTAssertEqual(CGFloat(-0.3333333333374246).rounded(by: 3), -0.3333333333333333)
+        XCTAssertEqual(CGFloat(-0.3333333333074246).rounded(by: 3), -0.3333333333333333)
+        XCTAssertEqual(CGFloat(0.33333333333374246).rounded(by: 3), 0.3333333333333333)
+        XCTAssertEqual(CGFloat(0.33333333333074246).rounded(by: 3), 0.3333333333333333)
+
+        XCTAssertEqual(CGFloat(-0.16666666666674246).rounded(by: 2), 0.0)
+        XCTAssertEqual(CGFloat(0.16666666666674246).rounded(by: 2), 0.0)
+
+        XCTAssertEqual(CGFloat(-0.16666666666674246).rounded(by: 6), -0.16666666666666666)
+        XCTAssertEqual(CGFloat(0.16666666666674246).rounded(by: 6), 0.16666666666666666)
+    }
 }

Tests/LayoutTests.swift

@@ -411,18 +411,18 @@ class LayoutTests: XCTestCase {
         for prop in [
             // from top edge
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .top, referenceGuide: .safeArea),
-             result: (#line, constant: 0.0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 0.0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .top, referenceGuide: .safeArea),
-             result: (#line, constant: 100.0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 100.0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .top, referenceGuide: .superview),
              result: (#line, constant: 0.0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .top, referenceGuide: .superview),
              result: (#line, constant: 100.0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.topAnchor)),
             // from bottom edge
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .bottom, referenceGuide: .safeArea),
-             result: (#line, constant: 0.0, firstAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.bottomAnchor)),
+             result: (#line, constant: 0.0, firstAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.bottomAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .bottom, referenceGuide: .safeArea),
-             result: (#line, constant: 100.0, firstAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.bottomAnchor)),
+             result: (#line, constant: 100.0, firstAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.bottomAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .bottom, referenceGuide: .superview),
              result: (#line, constant: 0.0, firstAnchor: fpc.view.bottomAnchor, secondAnchor: fpc.surfaceView.bottomAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .bottom, referenceGuide: .superview),
@@ -440,7 +440,7 @@ class LayoutTests: XCTestCase {
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .top, referenceGuide: .safeArea),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .top, referenceGuide: .safeArea),
-             result: (#line, multiplier: 0.5, secondAnchor: fpc.fp_safeAreaLayoutGuide.heightAnchor)),
+             result: (#line, multiplier: 0.5, secondAnchor: fpc.view.safeAreaLayoutGuide.heightAnchor)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .top, referenceGuide: .superview),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .top, referenceGuide: .superview),
@@ -450,7 +450,7 @@ class LayoutTests: XCTestCase {
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .bottom, referenceGuide: .safeArea),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .safeArea),
-             result: (#line, multiplier: 0.5, secondAnchor: fpc.fp_safeAreaLayoutGuide.heightAnchor)),
+             result: (#line, multiplier: 0.5, secondAnchor: fpc.view.safeAreaLayoutGuide.heightAnchor)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .bottom, referenceGuide: .superview),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .superview),
@@ -459,11 +459,7 @@ class LayoutTests: XCTestCase {
                 let c = prop.anchor.layoutConstraints(fpc, for: position)[0]
                 XCTAssertEqual(c.multiplier, CGFloat(prop.result.multiplier), line: UInt(prop.result.0))
                 XCTAssertTrue(c.firstAnchor is NSLayoutAnchor<NSLayoutDimension>, line: UInt(prop.result.0))
-                // On iOS 10, `c.secondAnchor` can't be equal object to `prop.result.secondAnchor`
-                // because there is no safe area  on iOS 10 and `fp_safeAreaLayoutGuide` emulates it.
-                if #available(iOS 11, *) {
-                    XCTAssertEqual(c.secondAnchor, prop.result.secondAnchor, line: UInt(prop.result.0))
-                }
+                XCTAssertEqual(c.secondAnchor, prop.result.secondAnchor, line: UInt(prop.result.0))
         }
     }
     func test_layoutAnchor_bottomPosition() {
@@ -476,9 +472,9 @@ class LayoutTests: XCTestCase {
         for prop in [
             // from top edge
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .top, referenceGuide: .safeArea),
-             result: (#line, constant: 0.0, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 0.0, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .top, referenceGuide: .safeArea),
-             result: (#line, constant: 100.0, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 100.0, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .top, referenceGuide: .superview),
              result: (#line, constant: 0.0, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .top, referenceGuide: .superview),
@@ -486,9 +482,9 @@ class LayoutTests: XCTestCase {
 
             // from bottom edge
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .bottom, referenceGuide: .safeArea),
-             result: (#line, constant: 0.0, firstAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.topAnchor)),
+             result: (#line, constant: 0.0, firstAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .bottom, referenceGuide: .safeArea),
-             result: (#line, constant: 100.0, firstAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.topAnchor)),
+             result: (#line, constant: 100.0, firstAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor, secondAnchor: fpc.surfaceView.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .bottom, referenceGuide: .superview),
              result: (#line, constant: 0.0, firstAnchor: fpc.view.bottomAnchor, secondAnchor: fpc.surfaceView.topAnchor)),
             (anchor: FloatingPanelLayoutAnchor(absoluteInset: 100.0, edge: .bottom, referenceGuide: .superview),
@@ -506,7 +502,7 @@ class LayoutTests: XCTestCase {
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .top, referenceGuide: .safeArea),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .top, referenceGuide: .safeArea),
-             result: (#line, multiplier: 0.5, secondAnchor: fpc.fp_safeAreaLayoutGuide.heightAnchor)),
+             result: (#line, multiplier: 0.5, secondAnchor: fpc.view.safeAreaLayoutGuide.heightAnchor)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .top, referenceGuide: .superview),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .top, referenceGuide: .superview),
@@ -516,7 +512,7 @@ class LayoutTests: XCTestCase {
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .bottom, referenceGuide: .safeArea),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .safeArea),
-             result: (#line, multiplier: 0.5, secondAnchor: fpc.fp_safeAreaLayoutGuide.heightAnchor)),
+             result: (#line, multiplier: 0.5, secondAnchor: fpc.view.safeAreaLayoutGuide.heightAnchor)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.0, edge: .bottom, referenceGuide: .superview),
              result: (#line, multiplier: 1.0, secondAnchor: nil)),
             (anchor: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .superview),
@@ -525,12 +521,7 @@ class LayoutTests: XCTestCase {
                 let c = prop.anchor.layoutConstraints(fpc, for: position)[0]
                 XCTAssertEqual(c.multiplier, CGFloat(prop.result.multiplier), line: UInt(prop.result.0))
                 XCTAssertTrue(c.firstAnchor is NSLayoutAnchor<NSLayoutDimension>, line: UInt(prop.result.0))
-                // On iOS 10, `c.secondAnchor` can't be equal object to `prop.result.secondAnchor`
-                // because there is no safe area  on iOS 10 and `fp_safeAreaLayoutGuide` emulates it.
-                if #available(iOS 11, *) {
-                    XCTAssertEqual(c.secondAnchor, prop.result.secondAnchor, line: UInt(prop.result.0))
-                }
-                print(c)
+                XCTAssertEqual(c.secondAnchor, prop.result.secondAnchor, line: UInt(prop.result.0))
         }
     }
 
@@ -556,20 +547,20 @@ class LayoutTests: XCTestCase {
 
         for prop in [
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 0.0, referenceGuide: .safeArea),
-             result: (#line, constant: 420, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 420, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 42.0, referenceGuide: .safeArea),
-             result: (#line, constant: 420 - 42, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 420 - 42, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 0.0, referenceGuide: .superview),
              result: (#line, constant: 420, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.topAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 42.0, referenceGuide: .superview),
              result: (#line, constant: 420 - 42, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.topAnchor)),
 
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.0, referenceGuide: .safeArea),
-             result: (#line, constant: 420, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 420, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.5, referenceGuide: .safeArea),
-             result: (#line, constant: 210, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 210, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 1.0, referenceGuide: .safeArea),
-             result: (#line, constant: 0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.topAnchor)),
+             result: (#line, constant: 0, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.topAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.0, referenceGuide: .superview),
              result: (#line, constant: 420, firstAnchor: fpc.surfaceView.bottomAnchor, secondAnchor: fpc.view.topAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.5, referenceGuide: .superview),
@@ -606,20 +597,20 @@ class LayoutTests: XCTestCase {
 
         for prop in [
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 0.0, referenceGuide: .safeArea),
-             result: (#line, constant: -420, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor)),
+             result: (#line, constant: -420, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 42.0, referenceGuide: .safeArea),
-             result: (#line, constant: -420 + 42, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor)),
+             result: (#line, constant: -420 + 42, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 0.0, referenceGuide: .superview),
              result: (#line, constant: -420, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.bottomAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(absoluteOffset: 42.0, referenceGuide: .superview),
              result: (#line, constant: -420 + 42, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.bottomAnchor)),
 
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.0, referenceGuide: .safeArea),
-             result: (#line, constant: -420, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor)),
+             result: (#line, constant: -420, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.5, referenceGuide: .safeArea),
-             result: (#line, constant: -210, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor)),
+             result: (#line, constant: -210, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 1.0, referenceGuide: .safeArea),
-             result: (#line, constant: 0, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.fp_safeAreaLayoutGuide.bottomAnchor)),
+             result: (#line, constant: 0, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.safeAreaLayoutGuide.bottomAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.0, referenceGuide: .superview),
              result: (#line, constant: -420, firstAnchor: fpc.surfaceView.topAnchor, secondAnchor: fpc.view.bottomAnchor)),
             (anchor: FloatingPanelIntrinsicLayoutAnchor(fractionalOffset: 0.5, referenceGuide: .superview),
@@ -633,6 +624,41 @@ class LayoutTests: XCTestCase {
                 XCTAssertEqual(c.secondAnchor, prop.result.secondAnchor, line: UInt(prop.result.0))
         }
     }
+
+    func test_offsetFromMostExpandedAnchor() {
+        do {
+            let fpc = FloatingPanelController()
+            fpc.layout = FloatingPanelBottomLayout()
+            fpc.showForTest()
+
+            fpc.move(to: .full, animated: false)
+
+            XCTAssertEqual(fpc.floatingPanel.layoutAdapter.offsetFromMostExpandedAnchor, 0.0)
+
+            fpc.move(to: .half, animated: false)
+
+            XCTAssertEqual(
+                fpc.floatingPanel.layoutAdapter.offsetFromMostExpandedAnchor,
+                (fpc.surfaceLocation(for: .half) - fpc.surfaceLocation(for: .full)).y
+            )
+        }
+        do {
+            let fpc = FloatingPanelController()
+            fpc.layout = FloatingPanelTopPositionedLayout()
+            fpc.showForTest()
+
+            fpc.move(to: .full, animated: false)
+
+            XCTAssertEqual(fpc.floatingPanel.layoutAdapter.offsetFromMostExpandedAnchor, 0.0)
+
+            fpc.move(to: .half, animated: false)
+
+            XCTAssertEqual(
+                fpc.floatingPanel.layoutAdapter.offsetFromMostExpandedAnchor,
+                -(fpc.surfaceLocation(for: .half) - fpc.surfaceLocation(for: .full)).y
+            )
+        }
+    }
 }
 
 private typealias LayoutSegmentTestParameter = (UInt, pos: CGFloat, forwardY: Bool, lower: FloatingPanelState?, upper: FloatingPanelState?)

Tests/TestSupports.swift

@@ -72,6 +72,16 @@ class FloatingPanelTop2BottomTestLayout: FloatingPanelLayout {
     }
 }
 
+class FloatingPanelTopPositionedLayout: FloatingPanelLayout {
+    let position: FloatingPanelPosition = .top
+    let initialState: FloatingPanelState = .full
+    let anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] = [
+        .full: FloatingPanelLayoutAnchor(absoluteInset: 88.0, edge: .bottom, referenceGuide: .safeArea),
+        .half: FloatingPanelLayoutAnchor(absoluteInset: 216.0, edge: .top, referenceGuide: .safeArea),
+        .tip: FloatingPanelLayoutAnchor(absoluteInset: 44.0, edge: .top, referenceGuide: .safeArea)
+    ]
+}
+
 class FloatingPanelProjectableBehavior: FloatingPanelBehavior {
     func shouldProjectMomentum(_ fpc: FloatingPanelController, to proposedState: FloatingPanelState) -> Bool {
         return true