Version 2.3.0

To fix a crash "Layout.swift: Fatal error: Attempted to read an unowned reference but the object was already deallocated"  which is reported at issue #440.

.github/FUNDING.yml

@@ -0,0 +1 @@
+github: SCENEE

.github/workflows/ci.yml

@@ -0,0 +1,81 @@
+name: ci
+
+on: 
+  push:
+    branches: 
+      - master
+  pull_request:
+    branches: 
+      - '*'
+
+jobs:
+  build:
+    runs-on: macOS-10.15
+    steps:
+    - uses: actions/checkout@v1
+    - name: "Swift 5.1"
+      run: xcodebuild -scheme FloatingPanel SWIFT_VERSION=5.1 clean build
+      env:
+        DEVELOPER_DIR: /Applications/Xcode_11.3.1.app/Contents/Developer
+    - name: "Swift 5.2"
+      run: xcodebuild -scheme FloatingPanel SWIFT_VERSION=5.2 clean build
+      env:
+        DEVELOPER_DIR: /Applications/Xcode_11.7.app/Contents/Developer
+    - name: "Swift 5.3"
+      run: xcodebuild -scheme FloatingPanel SWIFT_VERSION=5.3 clean build
+      env:
+        DEVELOPER_DIR: /Applications/Xcode_12.3.app/Contents/Developer
+
+  testing:
+    runs-on: macOS-10.15
+    steps:
+    - uses: actions/checkout@v1
+    - name: "Testing in iOS 13.7"
+      run: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=13.7,name=iPhone 11 Pro'
+      env:
+        DEVELOPER_DIR: /Applications/Xcode_11.7.app/Contents/Developer
+    - name: "Testing in iOS 14.3"
+      run: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=14.3,name=iPhone 12 Pro'
+      env:
+        DEVELOPER_DIR: /Applications/Xcode_12.3.app/Contents/Developer
+
+  example:
+    runs-on: macOS-10.15
+    env:
+      DEVELOPER_DIR: /Applications/Xcode_12.3.app/Contents/Developer
+    steps:
+    - uses: actions/checkout@v1
+    - name: "Build Maps"
+      run: xcodebuild -workspace FloatingPanel.xcworkspace -scheme Maps -sdk iphonesimulator clean build
+    - name: "Build Stocks"
+      run: xcodebuild -workspace FloatingPanel.xcworkspace -scheme Stocks -sdk iphonesimulator clean build
+    - name: "Build Samples"
+      run: xcodebuild -workspace FloatingPanel.xcworkspace -scheme Samples -sdk iphonesimulator clean build
+
+  swiftpm:
+    runs-on: macOS-10.15
+    env:
+      DEVELOPER_DIR: /Applications/Xcode_12.3.app/Contents/Developer
+    steps:
+    - uses: actions/checkout@v1
+    - name: "Swift Package build"
+      run: swift build -Xswiftc "-sdk" -Xswiftc "`xcrun --sdk iphonesimulator --show-sdk-path`" -Xswiftc "-target" -Xswiftc "x86_64-apple-ios14.3-simulator"
+
+  carthage:
+    runs-on: macOS-10.15
+    env:
+      # Carthage doesn't fix issues on Xcode 12: https://github.com/Carthage/Carthage/releases/tag/0.36.0
+      DEVELOPER_DIR: /Applications/Xcode_11.7.app/Contents/Developer
+    steps:
+    - uses: actions/checkout@v1
+    - name: "Carthage build"
+      run: carthage build --no-skip-current
+
+  cocoapods:
+    runs-on: macOS-10.15
+    steps:
+    - uses: actions/checkout@v1
+    - name: "CocoaPods: pod lib lint"
+      run: pod lib lint --allow-warnings
+    - name: "CocoaPods: pod spec lint"
+      run: pod spec lint --allow-warnings

.swiftformat

@@ -1,3 +1,3 @@
 --header "// Copyright 2018-Present Shin Yamamoto. All rights reserved. MIT license."
---disable andOperator,anyObjectProtocol,blankLinesAroundMark,blankLinesAtEndOfScope,blankLinesAtStartOfScope,blankLinesBetweenScopes,braces,consecutiveBlankLines,consecutiveSpaces,duplicateImports,elseOnSameLine,emptyBraces,hoistPatternLet,indent,isEmpty,leadingDelimiters,linebreakAtEndOfFile,linebreaks,numberFormatting,ranges,redundantBackticks,redundantBreak,redundantExtensionACL,redundantFileprivate,redundantGet,redundantInit,redundantLet,redundantLetError,redundantNilInit,redundantObjc,redundantParens,redundantPattern,redundantRawValues,redundantReturn,redundantSelf,redundantVoidReturnType,semicolons,sortedImports,spaceAroundBraces,spaceAroundBrackets,spaceAroundComments,spaceAroundGenerics,spaceAroundOperators,spaceAroundParens,spaceInsideBraces,spaceInsideBrackets,spaceInsideComments,spaceInsideGenerics,spaceInsideParens,specifiers,strongOutlets,strongifiedSelf,todos,trailingClosures,trailingCommas,trailingSpace,typeSugar,unusedArguments,void,wrapArguments,yodaConditions
+--disable andOperator,anyObjectProtocol,blankLinesAroundMark,blankLinesAtEndOfScope,blankLinesAtStartOfScope,blankLinesBetweenScopes,braces,consecutiveBlankLines,consecutiveSpaces,duplicateImports,elseOnSameLine,emptyBraces,hoistPatternLet,indent,isEmpty,leadingDelimiters,linebreakAtEndOfFile,linebreaks,numberFormatting,redundantBackticks,redundantBreak,redundantExtensionACL,redundantFileprivate,redundantGet,redundantInit,redundantLet,redundantLetError,redundantNilInit,redundantObjc,redundantParens,redundantPattern,redundantRawValues,redundantReturn,redundantSelf,redundantVoidReturnType,semicolons,sortedImports,spaceAroundBraces,spaceAroundBrackets,spaceAroundComments,spaceAroundGenerics,spaceAroundOperators,spaceAroundParens,spaceInsideBraces,spaceInsideBrackets,spaceInsideComments,spaceInsideGenerics,spaceInsideParens,specifiers,strongOutlets,strongifiedSelf,todos,trailingClosures,trailingCommas,trailingSpace,typeSugar,unusedArguments,void,wrapArguments,yodaConditions
 

.travis.yml

@@ -8,18 +8,6 @@ env:
   - LC_ALL=en_US.UTF-8
 jobs:
   include:
-  - stage: "Builds"
-    script: xcodebuild -scheme FloatingPanel SWIFT_VERSION=5.1 SUPPORTS_MACCATALYST=NO clean build
-    # SUPPORTS_MACCATALYST=NO because Xcode 11 runs on macOS 10.14 in Travis CI
-    osx_image: xcode11.3
-    name: "Swift 5.1"
-  - script: xcodebuild -scheme FloatingPanel SWIFT_VERSION=5.2 clean build
-    osx_image: xcode11.6
-    name: "Swift 5.2"
-  - script: xcodebuild -scheme FloatingPanel SWIFT_VERSION=5.3 clean build
-    osx_image: xcode12
-    name: "Swift 5.3"
-
   - stage: "Tests"
     script: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=10.3.1,name=iPhone SE (1st generation)'
     osx_image: xcode11.6
@@ -30,45 +18,3 @@ jobs:
   - script: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=12.4,name=iPhone X'
     osx_image: xcode11.6
     name: "iPhone X (iOS 12.4)"
-  - script: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=13.6,name=iPhone 11'
-    osx_image: xcode11.6
-    name: "iPhone X (iOS 13.6)"
-
-  - stage: "Build examples"
-    osx_image: xcode11.6
-    script: xcodebuild -workspace FloatingPanel.xcworkspace -scheme Maps -sdk iphonesimulator clean build
-    name: "Maps"
-  - script: xcodebuild -workspace FloatingPanel.xcworkspace -scheme Stocks -sdk iphonesimulator clean build
-    osx_image: xcode11.6
-    name: "Stocks"
-  - script: xcodebuild -workspace FloatingPanel.xcworkspace -scheme Samples -sdk iphonesimulator clean build
-    osx_image: xcode11.6
-    name: "Samples"
-  - script: xcodebuild -workspace FloatingPanel.xcworkspace -scheme SamplesObjC -sdk iphonesimulator clean build
-    osx_image: xcode11.6
-    name: "SamplesObjC"
-
-  - stage: "Swift Package Manager"
-    script: swift build -Xswiftc "-sdk" -Xswiftc "`xcrun --sdk iphoneos --show-sdk-path`" -Xswiftc "-target" -Xswiftc "arm64-apple-ios13.0"
-    osx_image: xcode11.6
-    name: "iPhone OS"
-  - script: swift build -Xswiftc "-sdk" -Xswiftc "`xcrun --sdk iphonesimulator --show-sdk-path`" -Xswiftc "-target" -Xswiftc "x86_64-apple-ios13.0-simulator"
-    osx_image: xcode11.6
-    name: "iPhone Simulator"
-
-  - stage: "Carthage"
-    # Carthage doesn't fix the issue with Xcode 12: https://github.com/Carthage/Carthage/releases/tag/0.36.0
-    osx_image: xcode11.6
-    before_install:
-    - brew update
-    - brew outdated carthage || brew upgrade carthage
-    script:
-    - carthage build --no-skip-current
-
-  - stage: "CocoaPods"
-    osx_image: xcode11.6
-    before_install: 
-    - gem install cocoapods
-    script:
-    - pod spec lint --allow-warnings
-    - pod lib lint --allow-warnings

Examples/Maps/Maps/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="16096" 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="17506" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
     <device id="retina5_9" orientation="portrait" appearance="light"/>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="16087"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="17505"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
@@ -28,6 +28,7 @@
                                 <blurEffect style="prominent"/>
                             </visualEffectView>
                         </subviews>
+                        <viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
                         <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                         <constraints>
                             <constraint firstItem="5Jw-n2-Cpw" firstAttribute="trailing" secondItem="8bC-Xf-vdC" secondAttribute="trailing" id="1Fg-Be-qfh"/>
@@ -39,7 +40,6 @@
                             <constraint firstItem="6Tk-OE-BBY" firstAttribute="top" secondItem="d9i-3g-8Ja" secondAttribute="bottom" id="Y1G-hr-aEX"/>
                             <constraint firstItem="d9i-3g-8Ja" firstAttribute="leading" secondItem="6Tk-OE-BBY" secondAttribute="leading" id="diB-Ij-HN3"/>
                         </constraints>
-                        <viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
                     </view>
                     <connections>
                         <outlet property="mapView" destination="5Jw-n2-Cpw" id="WVC-rU-mLe"/>
@@ -233,6 +233,7 @@
                                 <blurEffect style="prominent"/>
                             </visualEffectView>
                         </subviews>
+                        <viewLayoutGuide key="safeArea" id="G74-X7-Za8"/>
                         <color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                         <constraints>
                             <constraint firstItem="Ye3-uU-bq3" firstAttribute="leading" secondItem="G74-X7-Za8" secondAttribute="leading" id="Kr2-sU-ZWZ"/>
@@ -240,7 +241,6 @@
                             <constraint firstItem="Ye3-uU-bq3" firstAttribute="trailing" secondItem="G74-X7-Za8" secondAttribute="trailing" id="fEL-8y-Acc"/>
                             <constraint firstItem="Ye3-uU-bq3" firstAttribute="top" secondItem="Ncl-E9-yRn" secondAttribute="top" id="w77-ba-FrJ"/>
                         </constraints>
-                        <viewLayoutGuide key="safeArea" id="G74-X7-Za8"/>
                     </view>
                     <connections>
                         <outlet property="searchBar" destination="Zcj-SE-gb8" id="BH7-Gy-RG5"/>
@@ -262,7 +262,7 @@
                         <subviews>
                             <visualEffectView opaque="NO" contentMode="scaleToFill" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="c3d-2e-0b1">
                                 <rect key="frame" x="0.0" y="0.0" width="375" height="812"/>
-                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <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="375" height="812"/>
                                     <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
@@ -282,8 +282,8 @@
                                 <blurEffect style="extraLight"/>
                             </visualEffectView>
                         </subviews>
-                        <color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                         <viewLayoutGuide key="safeArea" id="ctv-Dd-JUc"/>
+                        <color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                     </view>
                 </viewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="EDp-D2-xcT" userLabel="First Responder" customClass="UIResponder" sceneMemberID="firstResponder"/>

Examples/Maps/Maps/SearchViewController.swift

@@ -21,6 +21,9 @@ extension ViewController: UITableViewDelegate {
 
     func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
         tableView.deselectRow(at: indexPath, animated: true)
+
+        deactivate(searchBar: searchVC.searchBar)
+
         // Show a detail panel
         switch indexPath.row {
         case 0:

Examples/Maps/Maps/ViewController.swift

@@ -83,14 +83,17 @@ class ViewController: UIViewController {
     func layoutPanelForPhone() {
         fpc.track(scrollView: searchVC.tableView) // Only track the tabvle view on iPhone
         fpc.addPanel(toParent: self, animated: true)
-        fpc.setApearanceForPhone()
-        detailFpc.setApearanceForPhone()
+        fpc.setAppearanceForPhone()
+        detailFpc.setAppearanceForPhone()
     }
 }
 
 extension FloatingPanelController {
-    func setApearanceForPhone() {
+    func setAppearanceForPhone() {
         let appearance = SurfaceAppearance()
+        if #available(iOS 13.0, *) {
+            appearance.cornerCurve = .continuous
+        }
         appearance.cornerRadius = 8.0
         appearance.backgroundColor = .clear
         surfaceView.appearance = appearance
@@ -114,19 +117,27 @@ extension FloatingPanelController {
 // MARK: - UISearchBarDelegate
 
 extension ViewController: UISearchBarDelegate {
-    func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
+    func activate(searchBar: UISearchBar) {
+        searchBar.showsCancelButton = true
+        searchVC.showHeader(animated: true)
+        searchVC.tableView.alpha = 1.0
+        detailVC.dismiss(animated: true, completion: nil)
+    }
+    func deactivate(searchBar: UISearchBar) {
         searchBar.resignFirstResponder()
         searchBar.showsCancelButton  = false
         searchVC.hideHeader(animated: true)
+    }
+
+    func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
+        deactivate(searchBar: searchBar)
         UIView.animate(withDuration: 0.25) {
             self.fpc.move(to: .half, animated: false)
         }
     }
 
     func searchBarTextDidBeginEditing(_ searchBar: UISearchBar) {
-        searchBar.showsCancelButton = true
-        searchVC.showHeader(animated: true)
-        searchVC.tableView.alpha = 1.0
+        activate(searchBar: searchBar)
         UIView.animate(withDuration: 0.25) { [weak self] in
             self?.fpc.move(to: .full, animated: false)
         }

Examples/Samples/Samples.xcodeproj/project.pbxproj

@@ -14,9 +14,11 @@
 		545DB9F821511E6400CA77B8 /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 545DB9F621511E6400CA77B8 /* LaunchScreen.storyboard */; };
 		545DBA0321511E6400CA77B8 /* SampleTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 545DBA0221511E6400CA77B8 /* SampleTests.swift */; };
 		545DBA0E21511E6400CA77B8 /* SampleUITests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 545DBA0D21511E6400CA77B8 /* SampleUITests.swift */; };
+		546341A125C6415100CA0596 /* UseCases.swift in Sources */ = {isa = PBXBuildFile; fileRef = 546341A025C6415100CA0596 /* UseCases.swift */; };
+		546341AC25C6426500CA0596 /* CustomState.swift in Sources */ = {isa = PBXBuildFile; fileRef = 546341AB25C6426500CA0596 /* CustomState.swift */; };
 		549D23CB233C7779008EF4D7 /* FloatingPanel.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 549D23CA233C7779008EF4D7 /* FloatingPanel.framework */; };
 		549D23CC233C7779008EF4D7 /* FloatingPanel.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 549D23CA233C7779008EF4D7 /* FloatingPanel.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
-		54B51116216AFE5F0033A6F3 /* UIExtensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54B51115216AFE5F0033A6F3 /* UIExtensions.swift */; };
+		54B51116216AFE5F0033A6F3 /* Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54B51115216AFE5F0033A6F3 /* Extensions.swift */; };
 		54CDC5D8215BBE23007D205C /* UIComponents.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54CDC5D7215BBE23007D205C /* UIComponents.swift */; };
 /* End PBXBuildFile section */
 
@@ -65,8 +67,10 @@
 		545DBA0921511E6400CA77B8 /* SamplesUITests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = SamplesUITests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		545DBA0D21511E6400CA77B8 /* SampleUITests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SampleUITests.swift; sourceTree = "<group>"; };
 		545DBA0F21511E6400CA77B8 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
+		546341A025C6415100CA0596 /* UseCases.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UseCases.swift; sourceTree = "<group>"; };
+		546341AB25C6426500CA0596 /* CustomState.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CustomState.swift; sourceTree = "<group>"; };
 		549D23CA233C7779008EF4D7 /* FloatingPanel.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = FloatingPanel.framework; sourceTree = BUILT_PRODUCTS_DIR; };
-		54B51115216AFE5F0033A6F3 /* UIExtensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UIExtensions.swift; sourceTree = "<group>"; };
+		54B51115216AFE5F0033A6F3 /* Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Extensions.swift; sourceTree = "<group>"; };
 		54CDC5D7215BBE23007D205C /* UIComponents.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UIComponents.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
@@ -125,8 +129,9 @@
 				545DB9F121511E6300CA77B8 /* Main.storyboard */,
 				545DB9ED21511E6300CA77B8 /* AppDelegate.swift */,
 				545DB9EF21511E6300CA77B8 /* ViewController.swift */,
-				54B51115216AFE5F0033A6F3 /* UIExtensions.swift */,
+				54B51115216AFE5F0033A6F3 /* Extensions.swift */,
 				54CDC5D7215BBE23007D205C /* UIComponents.swift */,
+				546341AA25C6421000CA0596 /* UseCases */,
 				545DB9F921511E6400CA77B8 /* Info.plist */,
 			);
 			path = Sources;
@@ -150,6 +155,15 @@
 			path = UITests;
 			sourceTree = "<group>";
 		};
+		546341AA25C6421000CA0596 /* UseCases */ = {
+			isa = PBXGroup;
+			children = (
+				546341A025C6415100CA0596 /* UseCases.swift */,
+				546341AB25C6426500CA0596 /* CustomState.swift */,
+			);
+			path = UseCases;
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXNativeTarget section */
@@ -304,7 +318,9 @@
 			buildActionMask = 2147483647;
 			files = (
 				54CDC5D8215BBE23007D205C /* UIComponents.swift in Sources */,
-				54B51116216AFE5F0033A6F3 /* UIExtensions.swift in Sources */,
+				54B51116216AFE5F0033A6F3 /* Extensions.swift in Sources */,
+				546341AC25C6426500CA0596 /* CustomState.swift in Sources */,
+				546341A125C6415100CA0596 /* UseCases.swift in Sources */,
 				545DB9F021511E6300CA77B8 /* ViewController.swift in Sources */,
 				545DB9EE21511E6300CA77B8 /* AppDelegate.swift in Sources */,
 			);

Examples/Samples/Sources/Assets.xcassets/Contents.json

@@ -1,6 +1,6 @@
 {
   "info" : {
-    "version" : 1,
-    "author" : "xcode"
+    "author" : "xcode",
+    "version" : 1
   }
-}
+}

Examples/Samples/Sources/Assets.xcassets/IMG_0003.imageset/Contents.json

@@ -0,0 +1,12 @@
+{
+  "images" : [
+    {
+      "filename" : "IMG_0003.jpg",
+      "idiom" : "universal"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

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

@@ -1,11 +1,12 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="17156" 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="17506" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="RoN-h0-uBD">
     <device id="retina5_9" orientation="portrait" appearance="light"/>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="17125"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="17505"/>
         <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"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <scenes>
@@ -293,6 +294,71 @@
             </objects>
             <point key="canvasLocation" x="2753" y="734"/>
         </scene>
+        <!--Image View Controller-->
+        <scene sceneID="NAI-Rh-ZQ6">
+            <objects>
+                <viewController storyboardIdentifier="ImageViewController" id="VWY-cF-RoY" customClass="ImageViewController" customModule="Samples" sceneMemberID="viewController">
+                    <view key="view" contentMode="scaleToFill" id="dAf-gD-ghB">
+                        <rect key="frame" x="0.0" y="0.0" width="375" height="778"/>
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <subviews>
+                            <stackView opaque="NO" contentMode="scaleToFill" axis="vertical" translatesAutoresizingMaskIntoConstraints="NO" id="Gs4-S6-Goh">
+                                <rect key="frame" x="0.0" y="0.0" width="375" height="778"/>
+                                <subviews>
+                                    <view contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" id="t7x-eG-MKh">
+                                        <rect key="frame" x="0.0" y="0.0" width="375" height="49"/>
+                                        <color key="backgroundColor" systemColor="systemOrangeColor"/>
+                                        <constraints>
+                                            <constraint firstAttribute="height" constant="49" id="DmG-pt-gij"/>
+                                        </constraints>
+                                    </view>
+                                    <scrollView clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="scaleToFill" alwaysBounceVertical="YES" alwaysBounceHorizontal="YES" showsHorizontalScrollIndicator="NO" showsVerticalScrollIndicator="NO" translatesAutoresizingMaskIntoConstraints="NO" id="kRA-qy-GpJ">
+                                        <rect key="frame" x="0.0" y="49" width="375" height="680"/>
+                                        <subviews>
+                                            <imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFill" horizontalHuggingPriority="1000" verticalHuggingPriority="1000" image="IMG_0003" translatesAutoresizingMaskIntoConstraints="NO" id="rGf-jW-WNf">
+                                                <rect key="frame" x="0.0" y="0.0" width="750" height="501"/>
+                                                <color key="backgroundColor" systemColor="systemPurpleColor"/>
+                                            </imageView>
+                                        </subviews>
+                                        <color key="backgroundColor" red="0.0078431372550000003" green="0.72156862749999995" blue="0.45882352939999999" alpha="1" colorSpace="calibratedRGB"/>
+                                        <constraints>
+                                            <constraint firstAttribute="trailing" secondItem="rGf-jW-WNf" secondAttribute="trailing" id="472-Be-cUl"/>
+                                            <constraint firstAttribute="bottom" secondItem="rGf-jW-WNf" secondAttribute="bottom" id="ncs-tN-3Wx"/>
+                                            <constraint firstItem="rGf-jW-WNf" firstAttribute="leading" secondItem="kRA-qy-GpJ" secondAttribute="leading" id="rlv-5Y-utR"/>
+                                            <constraint firstItem="rGf-jW-WNf" firstAttribute="top" secondItem="kRA-qy-GpJ" secondAttribute="top" id="zum-Zl-Wzz"/>
+                                        </constraints>
+                                    </scrollView>
+                                    <view contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" id="SEa-7Y-wa9">
+                                        <rect key="frame" x="0.0" y="729" width="375" height="49"/>
+                                        <color key="backgroundColor" systemColor="systemTealColor"/>
+                                        <constraints>
+                                            <constraint firstAttribute="height" constant="49" id="3mS-zi-8BP"/>
+                                        </constraints>
+                                    </view>
+                                </subviews>
+                            </stackView>
+                        </subviews>
+                        <viewLayoutGuide key="safeArea" id="hCg-v5-nJs"/>
+                        <color key="backgroundColor" systemColor="systemBackgroundColor"/>
+                        <constraints>
+                            <constraint firstAttribute="trailing" secondItem="Gs4-S6-Goh" secondAttribute="trailing" id="6z7-Md-pxr"/>
+                            <constraint firstAttribute="bottom" secondItem="Gs4-S6-Goh" secondAttribute="bottom" id="PcQ-bu-yT3"/>
+                            <constraint firstItem="Gs4-S6-Goh" firstAttribute="top" secondItem="dAf-gD-ghB" secondAttribute="top" id="zGx-Wd-hjz"/>
+                            <constraint firstItem="Gs4-S6-Goh" firstAttribute="leading" secondItem="dAf-gD-ghB" secondAttribute="leading" id="zxi-Ty-U7L"/>
+                        </constraints>
+                    </view>
+                    <size key="freeformSize" width="375" height="778"/>
+                    <connections>
+                        <outlet property="footerView" destination="SEa-7Y-wa9" id="Gzj-dP-YXl"/>
+                        <outlet property="headerView" destination="t7x-eG-MKh" id="njM-un-U8q"/>
+                        <outlet property="scrollView" destination="kRA-qy-GpJ" id="iWC-o4-APi"/>
+                        <outlet property="stackView" destination="Gs4-S6-Goh" id="f1D-bO-mjr"/>
+                    </connections>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="pnR-69-Ek4" userLabel="First Responder" customClass="UIResponder" sceneMemberID="firstResponder"/>
+            </objects>
+            <point key="canvasLocation" x="3388" y="734.48275862068965"/>
+        </scene>
         <!--Tab Bar View Controller-->
         <scene sceneID="nQ5-PV-qFw">
             <objects>
@@ -725,4 +791,19 @@ Section 1.10.33 of "de Finibus Bonorum et Malorum", written by Cicero in 45 BC
     <inferredMetricsTieBreakers>
         <segue reference="r1P-2i-NDe"/>
     </inferredMetricsTieBreakers>
+    <resources>
+        <image name="IMG_0003" width="750" height="501"/>
+        <systemColor name="systemBackgroundColor">
+            <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"/>
+        </systemColor>
+        <systemColor name="systemPurpleColor">
+            <color red="0.68627450980392157" green="0.32156862745098042" blue="0.87058823529411766" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+        </systemColor>
+        <systemColor name="systemTealColor">
+            <color red="0.35294117647058826" green="0.78431372549019607" blue="0.98039215686274506" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+        </systemColor>
+    </resources>
 </document>

Examples/Samples/Sources/UseCases/CustomState.swift

@@ -0,0 +1,22 @@
+// Copyright 2018-Present Shin Yamamoto. All rights reserved. MIT license.
+
+import Foundation
+import FloatingPanel
+
+extension FloatingPanelState {
+    static let lastQuart: FloatingPanelState = FloatingPanelState(rawValue: "lastQuart", order: 750)
+    static let firstQuart: FloatingPanelState = FloatingPanelState(rawValue: "firstQuart", order: 250)
+}
+
+class FloatingPanelLayoutWithCustomState: FloatingPanelBottomLayout {
+    override var anchors: [FloatingPanelState: FloatingPanelLayoutAnchoring] {
+        return [
+            .full: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .top, referenceGuide: .safeArea),
+            .lastQuart: FloatingPanelLayoutAnchor(fractionalInset: 0.75, edge: .bottom, referenceGuide: .safeArea),
+            .half: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .safeArea),
+            .firstQuart: FloatingPanelLayoutAnchor(fractionalInset: 0.25, edge: .bottom, referenceGuide: .safeArea),
+            .tip: FloatingPanelLayoutAnchor(absoluteInset: 20.0, edge: .bottom, referenceGuide: .safeArea),
+        ]
+    }
+}
+

Examples/Samples/Sources/UseCases/UseCases.swift

@@ -0,0 +1,78 @@
+// Copyright 2018-Present Shin Yamamoto. All rights reserved. MIT license.
+
+import Foundation
+
+enum UseCases: Int, CaseIterable {
+    case trackingTableView
+    case trackingTextView
+    case showDetail
+    case showModal
+    case showPanelModal
+    case showMultiPanelModal
+    case showPanelInSheetModal
+    case showTabBar
+    case showPageView
+    case showPageContentView
+    case showNestedScrollView
+    case showRemovablePanel
+    case showIntrinsicView
+    case showContentInset
+    case showContainerMargins
+    case showNavigationController
+    case showTopPositionedPanel
+    case showAdaptivePanel
+    case showAdaptivePanelWithCustomGuide
+    case showCustomStatePanel
+
+    var name: String {
+        switch self {
+        case .trackingTableView: return "Scroll tracking(TableView)"
+        case .trackingTextView: return "Scroll tracking(TextView)"
+        case .showDetail: return "Show Detail Panel"
+        case .showModal: return "Show Modal"
+        case .showPanelModal: return "Show Panel Modal"
+        case .showMultiPanelModal: return "Show Multi Panel Modal"
+        case .showPanelInSheetModal: return "Show Panel in Sheet Modal"
+        case .showTabBar: return "Show Tab Bar"
+        case .showPageView: return "Show Page View"
+        case .showPageContentView: return "Show Page Content View"
+        case .showNestedScrollView: return "Show Nested ScrollView"
+        case .showRemovablePanel: return "Show Removable Panel"
+        case .showIntrinsicView: return "Show Intrinsic View"
+        case .showContentInset: return "Show with ContentInset"
+        case .showContainerMargins: return "Show with ContainerMargins"
+        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 .showCustomStatePanel: return "Show Panel with Custom state"
+        }
+    }
+
+    var storyboardID: String? {
+        switch self {
+        case .trackingTableView: return nil
+        case .trackingTextView: return "ConsoleViewController"
+        case .showDetail: return "DetailViewController"
+        case .showModal: return "ModalViewController"
+        case .showMultiPanelModal: return nil
+        case .showPanelInSheetModal: return nil
+        case .showPanelModal: return nil
+        case .showTabBar: return "TabBarViewController"
+        case .showPageView: return nil
+        case .showPageContentView: return nil
+        case .showNestedScrollView: return "NestedScrollViewController"
+        case .showRemovablePanel: return "DetailViewController"
+        case .showIntrinsicView: return "IntrinsicViewController"
+        case .showContentInset: return nil
+        case .showContainerMargins: return nil
+        case .showNavigationController: return "RootNavigationController"
+        case .showTopPositionedPanel: return nil
+        case .showAdaptivePanel,
+             .showAdaptivePanelWithCustomGuide:
+            return "ImageViewController"
+        case .showCustomStatePanel:
+            return nil
+        }
+    }
+}

Examples/Samples/Sources/ViewController.swift

@@ -6,71 +6,7 @@ import FloatingPanel
 class SampleListViewController: UIViewController {
     @IBOutlet weak var tableView: UITableView!
 
-    enum Menu: Int, CaseIterable {
-        case trackingTableView
-        case trackingTextView
-        case showDetail
-        case showModal
-        case showPanelModal
-        case showMultiPanelModal
-        case showPanelInSheetModal
-        case showTabBar
-        case showPageView
-        case showPageContentView
-        case showNestedScrollView
-        case showRemovablePanel
-        case showIntrinsicView
-        case showContentInset
-        case showContainerMargins
-        case showNavigationController
-        case showBottomEdgeInteraction
-
-        var name: String {
-            switch self {
-            case .trackingTableView: return "Scroll tracking(TableView)"
-            case .trackingTextView: return "Scroll tracking(TextView)"
-            case .showDetail: return "Show Detail Panel"
-            case .showModal: return "Show Modal"
-            case .showPanelModal: return "Show Panel Modal"
-            case .showMultiPanelModal: return "Show Multi Panel Modal"
-            case .showPanelInSheetModal: return "Show Panel in Sheet Modal"
-            case .showTabBar: return "Show Tab Bar"
-            case .showPageView: return "Show Page View"
-            case .showPageContentView: return "Show Page Content View"
-            case .showNestedScrollView: return "Show Nested ScrollView"
-            case .showRemovablePanel: return "Show Removable Panel"
-            case .showIntrinsicView: return "Show Intrinsic View"
-            case .showContentInset: return "Show with ContentInset"
-            case .showContainerMargins: return "Show with ContainerMargins"
-            case .showNavigationController: return "Show Navigation Controller"
-            case .showBottomEdgeInteraction: return "Show bottom edge interaction"
-            }
-        }
-
-        var storyboardID: String? {
-            switch self {
-            case .trackingTableView: return nil
-            case .trackingTextView: return "ConsoleViewController"
-            case .showDetail: return "DetailViewController"
-            case .showModal: return "ModalViewController"
-            case .showMultiPanelModal: return nil
-            case .showPanelInSheetModal: return nil
-            case .showPanelModal: return nil
-            case .showTabBar: return "TabBarViewController"
-            case .showPageView: return nil
-            case .showPageContentView: return nil
-            case .showNestedScrollView: return "NestedScrollViewController"
-            case .showRemovablePanel: return "DetailViewController"
-            case .showIntrinsicView: return "IntrinsicViewController"
-            case .showContentInset: return nil
-            case .showContainerMargins: return nil
-            case .showNavigationController: return "RootNavigationController"
-            case .showBottomEdgeInteraction: return nil
-            }
-        }
-    }
-
-    var currentMenu: Menu = .trackingTableView
+    var currentMenu: UseCases = .trackingTableView
 
     var mainPanelVC: FloatingPanelController!
     var detailPanelVC: FloatingPanelController!
@@ -156,7 +92,7 @@ class SampleListViewController: UIViewController {
             mainPanelVC.backdropView.dismissalTapGestureRecognizer.isEnabled = true
         case .showNavigationController:
             mainPanelVC.contentInsetAdjustmentBehavior = .never
-        case .showBottomEdgeInteraction: // For debug
+        case .showTopPositionedPanel: // For debug
             let contentVC = UIViewController()
             contentVC.view.backgroundColor = .red
             mainPanelVC.set(contentViewController: contentVC)
@@ -184,6 +120,17 @@ class SampleListViewController: UIViewController {
                 rootVC.loadViewIfNeeded()
                 mainPanelVC.track(scrollView: rootVC.tableView)
             }
+        case let contentVC as ImageViewController:
+            if #available(iOS 11.0, *) {
+                let mode: ImageViewController.Mode = (currentMenu == .showAdaptivePanelWithCustomGuide) ? .withHeaderFooter : .onlyImage
+                let layoutGuide = contentVC.layoutGuideFor(mode: mode)
+                mainPanelVC.layout = ImageViewController.PanelLayout(targetGuide: layoutGuide)
+            } else {
+                mainPanelVC.layout = ImageViewController.PanelLayout(targetGuide: nil)
+            }
+            mainPanelVC.delegate = nil
+            mainPanelVC.isRemovalInteractionEnabled = true
+            mainPanelVC.track(scrollView: contentVC.scrollView)
         default:
             break
         }
@@ -236,19 +183,19 @@ extension SampleListViewController: UITableViewDataSource {
     func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
         if #available(iOS 11.0, *) {
             if navigationController?.navigationBar.prefersLargeTitles == true {
-                return Menu.allCases.count + 30
+                return UseCases.allCases.count + 30
             } else {
-                return Menu.allCases.count
+                return UseCases.allCases.count
             }
         } else {
-            return Menu.allCases.count
+            return UseCases.allCases.count
         }
     }
 
     func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
         let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
-        if Menu.allCases.count > indexPath.row {
-            let menu = Menu.allCases[indexPath.row]
+        if UseCases.allCases.count > indexPath.row {
+            let menu = UseCases.allCases[indexPath.row]
             cell.textLabel?.text = menu.name
         } else {
             cell.textLabel?.text = "\(indexPath.row) row"
@@ -259,8 +206,8 @@ extension SampleListViewController: UITableViewDataSource {
 
 extension SampleListViewController: UITableViewDelegate {
     func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
-        guard Menu.allCases.count > indexPath.row else { return }
-        let menu = Menu.allCases[indexPath.row]
+        guard UseCases.allCases.count > indexPath.row else { return }
+        let menu = UseCases.allCases[indexPath.row]
         let contentVC: UIViewController = {
             guard let storyboardID = menu.storyboardID else { return DebugTableViewController() }
             guard let vc = self.storyboard?.instantiateViewController(withIdentifier: storyboardID) else { fatalError() }
@@ -419,8 +366,8 @@ extension SampleListViewController: FloatingPanelControllerDelegate {
         }
 
         switch currentMenu {
-        case .showBottomEdgeInteraction:
-            return BottomEdgeInteractionLayout()
+        case .showTopPositionedPanel:
+            return TopPositionedPanelLayout()
         case .showRemovablePanel:
             return newCollection.verticalSizeClass == .compact ? RemovablePanelLandscapeLayout() :  RemovablePanelLayout()
         case .showIntrinsicView:
@@ -432,6 +379,8 @@ extension SampleListViewController: FloatingPanelControllerDelegate {
             fallthrough
         case .showContentInset:
             return FloatingPanelBottomLayout()
+        case .showCustomStatePanel:
+            return FloatingPanelLayoutWithCustomState()
         default:
             return (newCollection.verticalSizeClass == .compact) ? FloatingPanelBottomLayout() : self
         }
@@ -506,7 +455,7 @@ extension SampleListViewController: UIPageViewControllerDelegate {
     }
 }
 
-class BottomEdgeInteractionLayout: FloatingPanelLayout {
+class TopPositionedPanelLayout: FloatingPanelLayout {
     let position: FloatingPanelPosition = .top
     let initialState: FloatingPanelState = .full
 
@@ -1298,3 +1247,67 @@ final class MultiPanelController: FloatingPanelController, FloatingPanelControll
         }
     }
 }
+
+class ImageViewController: UIViewController {
+    class PanelLayout: FloatingPanelLayout {
+        weak var targetGuide: UILayoutGuide?
+        init(targetGuide: UILayoutGuide?) {
+            self.targetGuide = targetGuide
+        }
+        let position: FloatingPanelPosition = .bottom
+        let initialState: FloatingPanelState = .full
+        var anchors: [FloatingPanelState : FloatingPanelLayoutAnchoring] {
+            if #available(iOS 11.0, *), let targetGuide = targetGuide {
+                return [
+                    .full: FloatingPanelAdaptiveLayoutAnchor(absoluteOffset: 0,
+                                                             contentLayout: targetGuide,
+                                                             referenceGuide: .superview),
+                    .half: FloatingPanelAdaptiveLayoutAnchor(fractionalOffset: 0.5,
+                                                             contentLayout: targetGuide,
+                                                             referenceGuide: .superview)
+                ]
+            } else {
+                return [
+                    .full: FloatingPanelLayoutAnchor(absoluteInset: 500,
+                                                     edge: .bottom,
+                                                     referenceGuide: .superview)
+                ]
+            }
+        }
+    }
+
+    @IBOutlet weak var headerView: UIView!
+    @IBOutlet weak var footerView: UIView!
+    @IBOutlet weak var scrollView: UIScrollView!
+    @IBOutlet weak var stackView: UIStackView!
+
+    enum Mode {
+        case onlyImage
+        case withHeaderFooter
+    }
+
+    @available(iOS 11.0, *)
+    func layoutGuideFor(mode: Mode) -> UILayoutGuide {
+        switch mode {
+        case .onlyImage:
+            self.headerView.isHidden = true
+            self.footerView.isHidden = true
+            return scrollView.contentLayoutGuide
+        case .withHeaderFooter:
+            self.headerView.isHidden = false
+            self.footerView.isHidden = false
+            let guide = UILayoutGuide()
+            view.addLayoutGuide(guide)
+
+            NSLayoutConstraint.activate([
+                scrollView.heightAnchor.constraint(equalTo: scrollView.contentLayoutGuide.heightAnchor),
+
+                guide.topAnchor.constraint(equalTo: stackView.topAnchor),
+                guide.leftAnchor.constraint(equalTo: stackView.leftAnchor),
+                guide.bottomAnchor.constraint(equalTo: stackView.bottomAnchor),
+                guide.rightAnchor.constraint(equalTo: stackView.rightAnchor),
+            ])
+            return guide
+        }
+    }
+}

Examples/SamplesObjC/SamplesObjC/Assets.xcassets/Contents.json

@@ -1,6 +1,6 @@
 {
   "info" : {
-    "version" : 1,
-    "author" : "xcode"
+    "author" : "xcode",
+    "version" : 1
   }
-}
+}

Examples/SamplesObjC/SamplesObjC/ViewController.m

@@ -3,6 +3,22 @@
 #import "ViewController.h"
 @import FloatingPanel;
 
+// Defining a custom FloatingPanelState
+@interface FloatingPanelState(Extended)
++ (FloatingPanelState *)LastQuart;
+@end
+
+@implementation FloatingPanelState(Extended)
+static FloatingPanelState *_lastQuart;
++ (FloatingPanelState *)LastQuart {
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        _lastQuart = [[FloatingPanelState alloc] initWithRawValue:@"lastquart" order:750];
+    });
+    return _lastQuart;
+}
+@end
+
 @interface ViewController()<FloatingPanelControllerDelegate>
 @end
 
@@ -59,12 +75,15 @@
 }
 - (NSDictionary<FloatingPanelState *, id<FloatingPanelLayoutAnchoring>> *)anchors {
     return @{
+        FloatingPanelState.LastQuart: [[FloatingPanelLayoutAnchor alloc] initWithFractionalInset:0.25
+                                                                                       edge:FloatingPanelReferenceEdgeTop
+                                                                             referenceGuide:FloatingPanelLayoutReferenceGuideSafeArea],
         FloatingPanelState.Half: [[FloatingPanelLayoutAnchor alloc] initWithFractionalInset:0.5
                                                                                        edge:FloatingPanelReferenceEdgeTop
-                                                                         referenceGuide:FloatingPanelLayoutReferenceGuideSafeArea],
+                                                                             referenceGuide:FloatingPanelLayoutReferenceGuideSafeArea],
         FloatingPanelState.Tip: [[FloatingPanelLayoutAnchor alloc] initWithAbsoluteInset:44.0
                                                                                     edge:FloatingPanelReferenceEdgeBottom
-                                                                         referenceGuide:FloatingPanelLayoutReferenceGuideSafeArea],
+                                                                          referenceGuide:FloatingPanelLayoutReferenceGuideSafeArea],
     };
 }
 

FloatingPanel.podspec

@@ -1,7 +1,7 @@
 Pod::Spec.new do |s|
 
   s.name                = "FloatingPanel"
-  s.version             = "2.0.1"
+  s.version             = "2.3.0"
   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.

FloatingPanel.xcodeproj/project.pbxproj

@@ -9,7 +9,7 @@
 /* Begin PBXBuildFile section */
 		542753C622C49A6E00D17955 /* LayoutTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 542753C522C49A6E00D17955 /* LayoutTests.swift */; };
 		54352E9621A51A2500CBCA08 /* Transitioning.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54352E9521A51A2500CBCA08 /* Transitioning.swift */; };
-		54352E9821A521CA00CBCA08 /* PassThroughView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54352E9721A521CA00CBCA08 /* PassThroughView.swift */; };
+		54352E9821A521CA00CBCA08 /* PassthroughView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 54352E9721A521CA00CBCA08 /* PassthroughView.swift */; };
 		5450EEE421646DF500135936 /* Behavior.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5450EEE321646DF500135936 /* Behavior.swift */; };
 		545DB9CB2151169500CA77B8 /* FloatingPanel.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 545DB9C12151169500CA77B8 /* FloatingPanel.framework */; };
 		545DB9D02151169500CA77B8 /* ControllerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 545DB9CF2151169500CA77B8 /* ControllerTests.swift */; };
@@ -56,7 +56,7 @@
 		542753C522C49A6E00D17955 /* LayoutTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LayoutTests.swift; sourceTree = "<group>"; };
 		542753C722C49A8F00D17955 /* TestSupports.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TestSupports.swift; sourceTree = "<group>"; };
 		54352E9521A51A2500CBCA08 /* Transitioning.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Transitioning.swift; sourceTree = "<group>"; };
-		54352E9721A521CA00CBCA08 /* PassThroughView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PassThroughView.swift; sourceTree = "<group>"; };
+		54352E9721A521CA00CBCA08 /* PassthroughView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PassthroughView.swift; sourceTree = "<group>"; };
 		5450EEE321646DF500135936 /* Behavior.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Behavior.swift; sourceTree = "<group>"; };
 		545DB9C12151169500CA77B8 /* FloatingPanel.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FloatingPanel.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		545DB9C42151169500CA77B8 /* FloatingPanel.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FloatingPanel.h; sourceTree = "<group>"; };
@@ -142,7 +142,7 @@
 				5469F4B324B30F3500537F8A /* LayoutReferences.swift */,
 				5469F4AF24B30E1500537F8A /* LayoutAnchoring.swift */,
 				5450EEE321646DF500135936 /* Behavior.swift */,
-				54352E9721A521CA00CBCA08 /* PassThroughView.swift */,
+				54352E9721A521CA00CBCA08 /* PassthroughView.swift */,
 				54CDC5D2215B6D5A007D205C /* SurfaceView.swift */,
 				54CDC5D4215B6D8D007D205C /* BackdropView.swift */,
 				545DBA2A2152383100CA77B8 /* GrabberView.swift */,
@@ -328,7 +328,7 @@
 				54CFBFC3215CD045006B5735 /* Layout.swift in Sources */,
 				5469F4B424B30F3500537F8A /* LayoutReferences.swift in Sources */,
 				54CDC5D5215B6D8D007D205C /* BackdropView.swift in Sources */,
-				54352E9821A521CA00CBCA08 /* PassThroughView.swift in Sources */,
+				54352E9821A521CA00CBCA08 /* PassthroughView.swift in Sources */,
 				54CFBFC5215CD09C006B5735 /* Core.swift in Sources */,
 				54ABD7AF216CCFF7002E6C13 /* Logger.swift in Sources */,
 				545DB9E021511AC100CA77B8 /* Controller.swift in Sources */,

README.md

@@ -35,6 +35,8 @@ The new interface displays the related contents and utilities in parallel as a u
         - [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)
@@ -71,7 +73,7 @@ The new interface displays the related contents and utilities in parallel as a u
 - [x] Multi panel support
 - [x] Modal presentation
 - [x] 4 positioning support(top, left, bottom, right)
-- [x] 1~3 magnetic anchors(full, half, tip)
+- [x] 1 or more magnetic anchors(full, half, tip and more)
 - [x] Layout support for all trait environments(i.e. Landscape orientation)
 - [x] Common UI elements: surface, backdrop and grabber handle
 - [x] Free from common issues of Auto Layout and gesture handling
@@ -163,7 +165,7 @@ 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 [FloatingPanelTransitioning](https://github.com/SCENEE/FloatingPanel/blob/master/Framework/Sources/FloatingPanelTransitioning.swift).
+: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).
 
 ## View hierarchy
 
@@ -370,6 +372,46 @@ class MyFullScreenLayout: FloatingPanelLayout {
 
 :pencil2: `FloatingPanelFullScreenLayout` is deprecated on v1.
 
+#### Change the backdrop alpha
+
+You can change the backdrop alpha by `FloatingPanelLayout.backdropAlpha(for:)` for each state(`.full`, `.half` and `.tip`).
+
+For instance, if a panel seems like the backdrop view isn't there on `.half` state, it's time to implement the backdropAlpha API and return a value for the state as below.
+
+```swift
+class MyPanelLayout: FloatingPanelLayout {
+    func backdropAlpha(for state: FloatingPanelState) -> CGFloat {
+        switch state {
+        case .full, .half: return 0.3
+        default: return 0.0
+        }
+    }
+}
+```
+
+#### Using custome panel states
+
+You're able to define custom panel states and use them as the following example.
+
+```swift
+extension FloatingPanelState {
+    static let lastQuart: FloatingPanelState = FloatingPanelState(rawValue: "lastQuart", order: 750)
+    static let firstQuart: FloatingPanelState = FloatingPanelState(rawValue: "firstQuart", order: 250)
+}
+
+class FloatingPanelLayoutWithCustomState: FloatingPanelBottomLayout {
+    override var anchors: [FloatingPanelState: FloatingPanelLayoutAnchoring] {
+        return [
+            .full: FloatingPanelLayoutAnchor(absoluteInset: 0.0, edge: .top, referenceGuide: .safeArea),
+            .lastQuart: FloatingPanelLayoutAnchor(fractionalInset: 0.75, edge: .bottom, referenceGuide: .safeArea),
+            .half: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .safeArea),
+            .firstQuart: FloatingPanelLayoutAnchor(fractionalInset: 0.25, edge: .bottom, referenceGuide: .safeArea),
+            .tip: FloatingPanelLayoutAnchor(absoluteInset: 20.0, edge: .bottom, referenceGuide: .safeArea),
+        ]
+    }
+}
+```
+
 ### Customize the behavior with `FloatingPanelBehavior` protocol
 
 #### Modify your floating panel's interaction

Sources/Behavior.swift

@@ -43,44 +43,41 @@ public protocol FloatingPanelBehavior {
     /// This method allows a panel to activate the rubber band effect to a given edge of the surface view. By default, the effect is disabled.
     @objc optional
     func allowsRubberBanding(for edge: UIRectEdge) -> Bool
+    
+    /// Returns the velocity threshold for the default interactive removal gesture.
+    ///
+    /// In case `floatingPanel:shouldRemoveAt:with` is implemented, this value will not be used. The default value of `FloatingPanelDefaultBehavior` is 5.5
+    @objc optional
+    var removalInteractionVelocityThreshold: CGFloat { get }
 }
 
 /// The default behavior object for a panel
 ///
 /// This behavior object is fine-tuned to behave as a search panel(card) in Apple Maps on iPhone portrait orientation.
-public class FloatingPanelDefaultBehavior: FloatingPanelBehavior {
-    public var springDecelerationRate: CGFloat {
+open class FloatingPanelDefaultBehavior: FloatingPanelBehavior {
+    public init() {}
+
+    open var springDecelerationRate: CGFloat {
         return UIScrollView.DecelerationRate.fast.rawValue + 0.001
     }
 
-    public var springResponseTime: CGFloat {
+    open var springResponseTime: CGFloat {
         return 0.4
     }
 
-    public var momentumProjectionRate: CGFloat {
+    open var momentumProjectionRate: CGFloat {
         return UIScrollView.DecelerationRate.normal.rawValue
     }
 
-    public func redirectionalProgress(_ fpc: FloatingPanelController, from: FloatingPanelState, to: FloatingPanelState) -> CGFloat {
+    open func redirectionalProgress(_ fpc: FloatingPanelController, from: FloatingPanelState, to: FloatingPanelState) -> CGFloat {
         return 0.5
     }
 
-    func addPanelAnimator(_ fpc: FloatingPanelController, to: FloatingPanelState) -> UIViewPropertyAnimator {
-        return UIViewPropertyAnimator(duration: 0.0,
-                                      timingParameters: UISpringTimingParameters(decelerationRate: UIScrollView.DecelerationRate.fast.rawValue,
-                                                                                 frequencyResponse: 0.25))
-    }
-
-    func removePanelAnimator(_ fpc: FloatingPanelController, from: FloatingPanelState, with velocity: CGVector) -> UIViewPropertyAnimator {
-        return UIViewPropertyAnimator(duration: 0.0,
-                                      timingParameters: UISpringTimingParameters(decelerationRate: UIScrollView.DecelerationRate.fast.rawValue,
-                                                                                 frequencyResponse: 0.25,
-                                                                                 initialVelocity: velocity))
-    }
-
-    public func allowsRubberBanding(for edge: UIRectEdge) -> Bool {
+    open func allowsRubberBanding(for edge: UIRectEdge) -> Bool {
         return false
     }
+    
+    open var removalInteractionVelocityThreshold: CGFloat = 5.5
 }
 
 class BehaviorAdapter {
@@ -103,6 +100,10 @@ class BehaviorAdapter {
     var momentumProjectionRate: CGFloat {
         behavior.momentumProjectionRate ?? FloatingPanelDefaultBehavior().momentumProjectionRate
     }
+    
+    var removalInteractionVelocityThreshold: CGFloat {
+        behavior.removalInteractionVelocityThreshold ?? FloatingPanelDefaultBehavior().removalInteractionVelocityThreshold
+    }
 
     func redirectionalProgress(from: FloatingPanelState, to: FloatingPanelState) -> CGFloat {
         behavior.redirectionalProgress?(vc, from: from, to: to) ?? FloatingPanelDefaultBehavior().redirectionalProgress(vc,from: from, to: to)

Sources/Controller.swift

@@ -5,7 +5,7 @@ import UIKit
 /// A set of methods implemented by the delegate of a panel controller allows the adopting delegate to respond to
 /// messages from the FloatingPanelController class and thus respond to, and in some affect, operations such as
 /// dragging, attracting a panel, layout of a panel and the content, and transition animations.
-@objc public protocol FloatingPanelControllerDelegate: class {
+@objc public protocol FloatingPanelControllerDelegate {
     /// Returns a FloatingPanelLayout object. If you use the default one, you can use a `FloatingPanelBottomLayout` object.
     @objc(floatingPanel:layoutForTraitCollection:) optional
     func floatingPanel(_ fpc: FloatingPanelController, layoutFor newCollection: UITraitCollection) -> FloatingPanelLayout
@@ -274,7 +274,7 @@ open class FloatingPanelController: UIViewController {
     open override func loadView() {
         assert(self.storyboard == nil, "Storyboard isn't supported")
 
-        let view = PassThroughView()
+        let view = PassthroughView()
         view.backgroundColor = .clear
 
         backdropView.frame = view.bounds
@@ -498,7 +498,7 @@ open class FloatingPanelController: UIViewController {
             ])
 
         show(animated: animated) { [weak self] in
-            guard let `self` = self else { return }
+            guard let self = self else { return }
             self.didMove(toParent: parent)
         }
     }
@@ -517,7 +517,7 @@ open class FloatingPanelController: UIViewController {
         delegate?.floatingPanelWillRemove?(self)
 
         hide(animated: animated) { [weak self] in
-            guard let `self` = self else { return }
+            guard let self = self else { return }
 
             self.willMove(toParent: nil)
 
@@ -537,7 +537,6 @@ open class FloatingPanelController: UIViewController {
     ///     - completion: The block to execute after the view controller has finished moving. This block has no return value and takes no parameters. You may specify nil for this parameter.
     @objc(moveToState:animated:completion:)
     public func move(to: FloatingPanelState, animated: Bool, completion: (() -> Void)? = nil) {
-        assert(floatingPanel.layoutAdapter.vc != nil, "Use show(animated:completion)")
         floatingPanel.move(to: to, animated: animated, completion: completion)
     }
 
@@ -598,6 +597,14 @@ open class FloatingPanelController: UIViewController {
         }
     }
 
+    // MARK: - Accessibility
+
+    open override func accessibilityPerformEscape() -> Bool {
+        guard isRemovalInteractionEnabled else { return false }
+        dismiss(animated: true, completion: nil)
+        return true
+    }
+
     // MARK: - Utilities
 
     /// Updates the layout object from the delegate and lays out the views managed
@@ -641,10 +648,31 @@ extension FloatingPanelController {
         #endif
         delegate?.floatingPanelDidMove?(self)
     }
+
+    func animatorForPresenting(to: FloatingPanelState) -> UIViewPropertyAnimator {
+        if let animator = delegate?.floatingPanel?(self, animatorForPresentingTo: to) {
+            return animator
+        }
+        let timingParameters = UISpringTimingParameters(decelerationRate: UIScrollView.DecelerationRate.fast.rawValue,
+                                                       frequencyResponse: 0.25)
+        return UIViewPropertyAnimator(duration: 0.0,
+                                      timingParameters: timingParameters)
+    }
+
+    func animatorForDismissing(with velocity: CGVector) -> UIViewPropertyAnimator {
+        if let animator = delegate?.floatingPanel?(self, animatorForDismissingWith: velocity) {
+            return animator
+        }
+        let timingParameters = UISpringTimingParameters(decelerationRate: UIScrollView.DecelerationRate.fast.rawValue,
+                                                       frequencyResponse: 0.25,
+                                                       initialVelocity: velocity)
+        return UIViewPropertyAnimator(duration: 0.0,
+                                      timingParameters: timingParameters)
+    }
 }
 
 extension FloatingPanelController {
-    private static let dismissSwizzling: Any? = {
+    private static let dismissSwizzling: Void = {
         let aClass: AnyClass! = UIViewController.self //object_getClass(vc)
         if let imp = class_getMethodImplementation(aClass, #selector(dismiss(animated:completion:))),
             let originalAltMethod = class_getInstanceMethod(aClass, #selector(fp_original_dismiss(animated:completion:))) {
@@ -653,10 +681,8 @@ extension FloatingPanelController {
         let originalMethod = class_getInstanceMethod(aClass, #selector(dismiss(animated:completion:)))
         let swizzledMethod = class_getInstanceMethod(aClass, #selector(fp_dismiss(animated:completion:)))
         if let originalMethod = originalMethod, let swizzledMethod = swizzledMethod {
-            // switch implementation..
             method_exchangeImplementations(originalMethod, swizzledMethod)
         }
-        return nil
     }()
 }
 

Sources/Core.swift

@@ -32,7 +32,8 @@ class Core: NSObject, UIGestureRecognizerDelegate {
     let panGestureRecognizer: FloatingPanelPanGestureRecognizer
     var isRemovalInteractionEnabled: Bool = false
 
-    fileprivate var animator: UIViewPropertyAnimator?
+    fileprivate var isSuspended: Bool = false // Prevent a memory leak in the modal transition
+    fileprivate var transitionAnimator: UIViewPropertyAnimator?
     fileprivate var moveAnimator: NumericSpringAnimator?
 
     private var initialSurfaceLocation: CGPoint = .zero
@@ -68,11 +69,8 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         backdropView.backgroundColor = .black
         backdropView.alpha = 0.0
 
-        self.layoutAdapter = LayoutAdapter(vc: vc,
-                                           surfaceView: surfaceView,
-                                           backdropView: backdropView,
-                                           layout: layout)
-        self.behaviorAdapter = BehaviorAdapter(vc: vc, behavior: behavior)
+        layoutAdapter = LayoutAdapter(vc: vc, layout: layout)
+        behaviorAdapter = BehaviorAdapter(vc: vc, behavior: behavior)
 
         panGestureRecognizer = FloatingPanelPanGestureRecognizer()
 
@@ -94,6 +92,11 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         backdropView.addGestureRecognizer(tapGesture)
     }
 
+    deinit {
+        // Release `NumericSpringAnimator.displayLink` from the run loop.
+        self.moveAnimator?.stopAnimation(false)
+    }
+
     func move(to: FloatingPanelState, animated: Bool, completion: (() -> Void)? = nil) {
         move(from: state, to: to, animated: animated, completion: completion)
     }
@@ -112,7 +115,8 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         interruptAnimationIfNeeded()
 
         if animated {
-            func updateScrollView() {
+            let updateScrollView: () -> Void = { [weak self] in
+                guard let self = self else { return }
                 if self.state == self.layoutAdapter.edgeMostState, abs(self.layoutAdapter.offsetFromEdgeMost) <= 1.0 {
                     self.unlockScrollView()
                 } else {
@@ -123,14 +127,14 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             let animator: UIViewPropertyAnimator
             switch (from, to) {
             case (.hidden, let to):
-                animator = vc.delegate?.floatingPanel?(vc, animatorForPresentingTo: to)
-                    ?? FloatingPanelDefaultBehavior().addPanelAnimator(vc, to: to)
-            case (let from, .hidden):
+                animator = vc.animatorForPresenting(to: to)
+            case (_, .hidden):
                 let animationVector = CGVector(dx: abs(removalVector.dx), dy: abs(removalVector.dy))
-                animator = vc.delegate?.floatingPanel?(vc, animatorForDismissingWith: .zero)
-                    ?? FloatingPanelDefaultBehavior().removePanelAnimator(vc, from: from, with: animationVector)
+                animator = vc.animatorForDismissing(with: animationVector)
             default:
-                move(to: to, with: 0) {
+                move(to: to, with: 0) { [weak self] in
+                    guard let self = self else { return }
+
                     self.moveAnimator = nil
                     updateScrollView()
                     completion?()
@@ -143,7 +147,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                 && layoutAdapter.isIntrinsicAnchor(state: to)
 
             animator.addAnimations { [weak self] in
-                guard let `self` = self else { return }
+                guard let self = self else { return }
 
                 self.state = to
                 self.updateLayout(to: to)
@@ -154,13 +158,17 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                 }
             }
             animator.addCompletion { [weak self] _ in
-                guard let `self` = self else { return }
-                self.animator = nil
+                guard let self = self else { return }
+
+                self.transitionAnimator = nil
                 updateScrollView()
                 self.ownerVC?.notifyDidMove()
                 completion?()
             }
-            self.animator = animator
+            self.transitionAnimator = animator
+            if isSuspended {
+                return
+            }
             animator.startAnimation()
         } else {
             self.state = to
@@ -373,7 +381,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                 if interactionInProgress {
                     lockScrollView()
                 } else {
-                    if state == layoutAdapter.edgeMostState, self.animator == nil {
+                    if state == layoutAdapter.edgeMostState, self.transitionAnimator == nil {
                         switch layoutAdapter.position {
                         case .top, .left:
                             if offsetDiff < 0 && velocity > 0 {
@@ -493,7 +501,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             animator.stopAnimation(true)
             endAttraction(false)
         }
-        if let animator = self.animator {
+        if let animator = self.transitionAnimator {
             guard 0 >= layoutAdapter.offsetFromEdgeMost else { return }
             log.debug("a panel animation(interruptible: \(animator.isInterruptible)) interrupted!!!")
             if animator.isInterruptible {
@@ -535,15 +543,20 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             return false
         }
 
-        // When the current and initial point within grabber area, do scroll.
+        // When the current point is within grabber area but the initial point is not, do scroll.
         if grabberAreaFrame.contains(point), !grabberAreaFrame.contains(initialLocation) {
             return true
         }
 
+        // When the initial point is within grabber area and the current point is out of surface, don't scroll.
+        if grabberAreaFrame.contains(initialLocation), !surfaceView.frame.contains(point) {
+            return false
+        }
+
         let scrollViewFrame = scrollView.convert(scrollView.bounds, to: surfaceView)
         guard
-            scrollViewFrame.contains(initialLocation), // When initialLocation not in scrollView, don't scroll.
-            !grabberAreaFrame.contains(point)           // When point within grabber area, don't scroll.
+            scrollViewFrame.contains(initialLocation), // When the initial point not in scrollView, don't scroll.
+            !grabberAreaFrame.contains(point)          // When point within grabber area, don't scroll.
         else {
             return false
         }
@@ -571,6 +584,9 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         if scrollView.isDecelerating {
             return true
         }
+        if let tableView = (scrollView as? UITableView), tableView.isEditing {
+            return true
+        }
 
         return false
     }
@@ -652,7 +668,8 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         stopScrollDeceleration = (0 > layoutAdapter.offsetFromEdgeMost + (1.0 / surfaceView.fp_displayScale)) // Projecting the dragging to the scroll dragging or not
         if stopScrollDeceleration {
             DispatchQueue.main.async { [weak self] in
-                guard let `self` = self else { return }
+                guard let self = self else { return }
+
                 self.stopScrolling(at: self.initialScrollOffset)
             }
         }
@@ -698,14 +715,14 @@ class Core: NSObject, UIGestureRecognizerDelegate {
 
         // Workaround: Disable a tracking scroll to prevent bouncing a scroll content in a panel animating
         let isScrollEnabled = scrollView?.isScrollEnabled
-        if let scrollView = scrollView, targetPosition != .full {
+        if let scrollView = scrollView, targetPosition != layoutAdapter.edgeMostState {
             scrollView.isScrollEnabled = false
         }
 
         startAttraction(to: targetPosition, with: velocity)
 
         // Workaround: Reset `self.scrollView.isScrollEnabled`
-        if let scrollView = scrollView, targetPosition != .full,
+        if let scrollView = scrollView, targetPosition != layoutAdapter.edgeMostState,
             let isScrollEnabled = isScrollEnabled {
             scrollView.isScrollEnabled = isScrollEnabled
         }
@@ -718,7 +735,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         if let result = vc.delegate?.floatingPanel?(vc, shouldRemoveAt: vc.surfaceLocation, with: velocityVector) {
             return result
         }
-        let threshold = CGFloat(5.5)
+        let threshold = behaviorAdapter.removalInteractionVelocityThreshold
         switch layoutAdapter.position {
         case .top:
             return (velocityVector.dy <= -threshold)
@@ -825,15 +842,18 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             decelerationRate: behaviorAdapter.springDecelerationRate,
             responseTime: behaviorAdapter.springResponseTime,
             update: { [weak self] data in
-                guard let self = self else { return }
+                guard let self = self,
+                      let ownerVC = self.ownerVC // Ensure the owner vc is existing for `layoutAdapter.surfaceLocation`
+                else { return }
                 animationConstraint.constant = data.value
                 let current = self.value(of: self.layoutAdapter.surfaceLocation)
                 let translation = data.value - initialData.value
                 self.backdropView.alpha = self.getBackdropAlpha(at: current, with: translation)
-                self.ownerVC?.notifyDidMove()
+                ownerVC.notifyDidMove()
         },
             completion: { [weak self] in
-                guard let self = self else { return }
+                guard let self = self,
+                      self.ownerVC != nil else { return }
                 self.layoutAdapter.activateLayout(for: targetPosition, forceLayout: true)
                 completion()
         })
@@ -1023,7 +1043,7 @@ public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
     public override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
         super.touchesBegan(touches, with: event)
         initialLocation = touches.first?.location(in: view) ?? .zero
-        if floatingPanel?.animator != nil || floatingPanel?.moveAnimator != nil {
+        if floatingPanel?.transitionAnimator != nil || floatingPanel?.moveAnimator != nil {
             self.state = .began
         }
     }
@@ -1184,3 +1204,12 @@ private class NumericSpringAnimator: NSObject {
         v = (v + h * o2 * (xt - x)) / det
     }
 }
+
+extension FloatingPanelController {
+    func suspendTransitionAnimator(_ suspended: Bool) {
+        self.floatingPanel.isSuspended = suspended
+    }
+    var transitionAnimator: UIViewPropertyAnimator? {
+        return self.floatingPanel.transitionAnimator
+    }
+}

Sources/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.0.1</string>
+	<string>2.3.0</string>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
 </dict>

Sources/Layout.swift

@@ -60,9 +60,7 @@ struct LayoutSegment {
 }
 
 class LayoutAdapter {
-    weak var vc: FloatingPanelController!
-    private weak var surfaceView: SurfaceView!
-    private weak var backdropView: BackdropView!
+    private unowned var vc: FloatingPanelController
     private let defaultLayout = FloatingPanelBottomLayout()
 
     fileprivate var layout: FloatingPanelLayout {
@@ -71,16 +69,21 @@ class LayoutAdapter {
         }
     }
 
+    private var surfaceView: SurfaceView {
+        return vc.surfaceView
+    }
+    private var backdropView: BackdropView {
+        return vc.backdropView
+    }
     private var safeAreaInsets: UIEdgeInsets {
-        return vc?.fp_safeAreaInsets ?? .zero
+        return vc.fp_safeAreaInsets
     }
 
     private var initialConst: CGFloat = 0.0
 
     private var fixedConstraints: [NSLayoutConstraint] = []
-    private var fullConstraints: [NSLayoutConstraint] = []
-    private var halfConstraints: [NSLayoutConstraint] = []
-    private var tipConstraints: [NSLayoutConstraint] = []
+
+    private var stateConstraints: [FloatingPanelState: [NSLayoutConstraint]] = [:]
     private var offConstraints: [NSLayoutConstraint] = []
     private var fitToBoundsConstraint: NSLayoutConstraint?
 
@@ -284,14 +287,9 @@ class LayoutAdapter {
         }
     }
 
-    init(vc: FloatingPanelController,
-         surfaceView: SurfaceView,
-         backdropView: BackdropView,
-         layout: FloatingPanelLayout) {
+    init(vc: FloatingPanelController, layout: FloatingPanelLayout) {
         self.vc = vc
         self.layout = layout
-        self.surfaceView = surfaceView
-        self.backdropView = backdropView
     }
 
     func surfaceLocation(for state: FloatingPanelState) -> CGPoint {
@@ -327,6 +325,22 @@ class LayoutAdapter {
                 }
                 return base - intrinsicLength + diff
             }
+        case let anchor as FloatingPanelAdaptiveLayoutAnchor:
+            let dimension = layout.position.mainDimension(anchor.contentLayoutGuide.layoutFrame.size)
+            let diff = anchor.distance(from: dimension)
+            var referenceBoundsLength = layout.position.mainDimension(bounds.size)
+            switch layout.position {
+            case .top, .left:
+                if anchor.referenceGuide == .safeArea {
+                    referenceBoundsLength += position.inset(safeAreaInsets)
+                }
+                return dimension - diff
+            case .bottom, .right:
+                if anchor.referenceGuide == .safeArea {
+                    referenceBoundsLength -= position.inset(safeAreaInsets)
+                }
+                return referenceBoundsLength - dimension + diff
+            }
         case let anchor as FloatingPanelLayoutAnchor:
             let referenceBounds = anchor.referenceGuide == .safeArea ? bounds.inset(by: safeAreaInsets) : bounds
             let diff = anchor.isAbsolute ? anchor.inset : position.mainDimension(referenceBounds.size) * anchor.inset
@@ -364,7 +378,8 @@ class LayoutAdapter {
 
     private func referenceEdge(of anchor: FloatingPanelLayoutAnchoring) -> FloatingPanelReferenceEdge {
         switch anchor {
-        case is FloatingPanelIntrinsicLayoutAnchor:
+        case is FloatingPanelIntrinsicLayoutAnchor,
+            is FloatingPanelAdaptiveLayoutAnchor:
             switch position {
             case .top: return .top
             case .left: return .left
@@ -436,25 +451,13 @@ class LayoutAdapter {
     }
 
     private func updateStateConstraints() {
-        NSLayoutConstraint.deactivate(fullConstraints + halfConstraints + tipConstraints + offConstraints)
-
-        if let fullAnchor = layout.anchors[.full] {
-            fullConstraints = fullAnchor.layoutConstraints(vc, for: position)
-            fullConstraints.forEach {
-                $0.identifier = "FloatingPanel-full-constraint"
-            }
-        }
-        if let halfAnchor = layout.anchors[.half] {
-            halfConstraints = halfAnchor.layoutConstraints(vc, for: position)
-            halfConstraints.forEach {
-                $0.identifier = "FloatingPanel-half-constraint"
-            }
-        }
-        if let tipAnchors = layout.anchors[.tip] {
-            tipConstraints = tipAnchors.layoutConstraints(vc, for: position)
-            tipConstraints.forEach {
-                $0.identifier = "FloatingPanel-tip-constraint"
-            }
+        let allStateConstraints = stateConstraints.flatMap { $1 }
+        NSLayoutConstraint.deactivate(allStateConstraints + offConstraints)
+        stateConstraints.removeAll()
+        for state in layout.anchors.keys {
+            stateConstraints[state] = layout.anchors[state]?
+                .layoutConstraints(vc, for: position)
+                .map{ $0.identifier = "FloatingPanel-\(state)-constraint"; return $0 }
         }
         let hiddenAnchor = layout.anchors[.hidden] ?? self.hiddenAnchor
         offConstraints = hiddenAnchor.layoutConstraints(vc, for: position)
@@ -471,7 +474,7 @@ class LayoutAdapter {
 
         tearDownAttraction()
 
-        NSLayoutConstraint.deactivate(fullConstraints + halfConstraints + tipConstraints + offConstraints)
+        NSLayoutConstraint.deactivate(stateConstraints.flatMap { $1 } + offConstraints)
 
         initialConst = edgePosition(surfaceView.frame) + offset.y
 
@@ -487,7 +490,7 @@ class LayoutAdapter {
             constraint = surfaceView.leftAnchor.constraint(equalTo: vc.view.leftAnchor, constant: initialConst)
         }
 
-        constraint.priority = .defaultHigh
+        constraint.priority = .required
         constraint.identifier = "FloatingPanel-interaction"
 
         NSLayoutConstraint.activate([constraint])
@@ -511,7 +514,7 @@ class LayoutAdapter {
 
         let anchor = layout.anchors[state] ?? self.hiddenAnchor
 
-        NSLayoutConstraint.deactivate(fullConstraints + halfConstraints + tipConstraints + offConstraints)
+        NSLayoutConstraint.deactivate(stateConstraints.flatMap { $1 } + offConstraints)
         NSLayoutConstraint.deactivate(constraint: interactionConstraint)
         interactionConstraint = nil
 
@@ -630,7 +633,6 @@ class LayoutAdapter {
     // The method is separated from prepareLayout(to:) for the rotation support
     // It must be called in FloatingPanelController.traitCollectionDidChange(_:)
     func updateStaticConstraint() {
-        guard let vc = vc else { return }
         NSLayoutConstraint.deactivate(constraint: staticConstraint)
         staticConstraint = nil
 
@@ -640,19 +642,31 @@ class LayoutAdapter {
         }
 
         let anchor = layout.anchors[self.edgeMostState]!
-        if anchor is FloatingPanelIntrinsicLayoutAnchor {
-            var constant = layout.position.mainDimension(surfaceView.intrinsicContentSize)
+        let surfaceAnchor = position.mainDimensionAnchor(surfaceView)
+        switch anchor {
+        case let anchor as FloatingPanelIntrinsicLayoutAnchor:
+            var constant = position.mainDimension(surfaceView.intrinsicContentSize)
             if anchor.referenceGuide == .safeArea {
                 constant += position.inset(safeAreaInsets)
             }
-            staticConstraint = position.mainDimensionAnchor(surfaceView).constraint(equalToConstant: constant)
-        } else {
+            staticConstraint = surfaceAnchor.constraint(equalToConstant: constant)
+        case let anchor as FloatingPanelAdaptiveLayoutAnchor:
+            let constant: CGFloat
+            if anchor.referenceGuide == .safeArea {
+                constant = position.inset(safeAreaInsets)
+            } else {
+                constant = 0.0
+            }
+            let baseAnchor = position.mainDimensionAnchor(anchor.contentLayoutGuide)
+            staticConstraint = surfaceAnchor.constraint(equalTo: baseAnchor, constant: constant)
+        default:
             switch position {
             case .top, .left:
-                staticConstraint = position.mainDimensionAnchor(surfaceView).constraint(equalToConstant: position(for: self.directionalMostState))
+                staticConstraint = surfaceAnchor.constraint(equalToConstant: position(for: self.directionalMostState))
             case .bottom, .right:
-                staticConstraint = position.mainDimensionAnchor(vc.view).constraint(equalTo: position.mainDimensionAnchor(surfaceView),
-                                                                                    constant: position(for: self.directionalLeastState))
+                let rootViewAnchor = position.mainDimensionAnchor(vc.view)
+                staticConstraint = rootViewAnchor.constraint(equalTo: surfaceAnchor,
+                                                             constant: position(for: self.directionalLeastState))
             }
         }
 
@@ -741,17 +755,16 @@ class LayoutAdapter {
         // on-screen and off-screen view which includes
         // UIStackView(i.e. Settings view in Samples.app)
         updateStateConstraints()
+
         switch state {
-        case .full:
-            NSLayoutConstraint.activate(fullConstraints)
-        case .half:
-            NSLayoutConstraint.activate(halfConstraints)
-        case .tip:
-            NSLayoutConstraint.activate(tipConstraints)
         case .hidden:
             NSLayoutConstraint.activate(offConstraints)
         default:
-            break
+            if let constraints = stateConstraints[state] {
+                NSLayoutConstraint.activate(constraints)
+            } else {
+                log.error("Couldn't find any constraints for \(state)")
+            }
         }
     }
 

Sources/LayoutAnchoring.swift

@@ -8,22 +8,25 @@ import UIKit
     func layoutConstraints(_ fpc: FloatingPanelController, for position: FloatingPanelPosition) -> [NSLayoutConstraint]
 }
 
-/// A layout anchor object that anchors a panel in a state.
+/// An object that defines how to settles a panel with insets from an edge of a reference rectangle.
 @objc final public class FloatingPanelLayoutAnchor: NSObject, FloatingPanelLayoutAnchoring /*, NSCopying */ {
-    /// Initializes and returns a layout anchor object to specify an absolute inset value for the position of a panel.
+
+    /// Returns a layout anchor with the specified inset by an absolute value, edge and reference guide for a panel.
     ///
-    /// The inset is a distance from the edge of the specified layout guide.
+    /// The inset is an amount to inset a panel from an edge of the reference guide.  The edge refers to a panel
+    /// positioning.
     @objc public init(absoluteInset: CGFloat, edge: FloatingPanelReferenceEdge, referenceGuide: FloatingPanelLayoutReferenceGuide) {
         self.inset = absoluteInset
         self.referenceGuide = referenceGuide
         self.referenceEdge = edge
         self.isAbsolute = true
     }
-    /// Initializes and returns a layout anchor object to specify a fractional inset value for the position of a panel.
+
+    /// Returns a layout anchor with the specified inset by a fractional value, edge and reference guide for a panel.
     ///
-    /// The inset is a distance from the edge of the specified layout guide. The value is a floating-point number
-    /// in the range 0.0 to 1.0, where 0.0 represents zero distance from the edge and 1.0 represents a distance
-    /// to the opposite edge.
+    /// The inset is an amount to inset a panel from the edge of the specified reference guide. The value is
+    /// a floating-point number in the range 0.0 to 1.0, where 0.0 represents zero distance from the edge and
+    /// 1.0 represents a distance to the opposite edge.
     @objc public init(fractionalInset: CGFloat, edge: FloatingPanelReferenceEdge, referenceGuide: FloatingPanelLayoutReferenceGuide) {
         self.inset = fractionalInset
         self.referenceGuide = referenceGuide
@@ -91,19 +94,20 @@ public extension FloatingPanelLayoutAnchor {
     }
 }
 
-
-/// A layout anchor object that anchors a panel in a state using the intrinsic size for a content.
+/// An object that defines how to settles a panel with the intrinsic size for a content.
 @objc final public class FloatingPanelIntrinsicLayoutAnchor: NSObject, FloatingPanelLayoutAnchoring /*, NSCopying */ {
-    /// Initializes and returns a layout anchor object to specify an absolute offset value for the position of a panel.
+
+    /// Returns a layout anchor with the specified offset by an absolute value and reference guide for a panel.
     ///
-    /// The offset is a distance from a position at which a panel displays the entire content.
+    /// The offset is an amount to offset a position of panel that displays the entire content from an edge of
+    /// the reference guide.  The edge refers to a panel positioning.
     @objc public init(absoluteOffset offset: CGFloat, referenceGuide: FloatingPanelLayoutReferenceGuide = .safeArea) {
         self.offset = offset
         self.referenceGuide = referenceGuide
         self.isAbsolute = true
     }
 
-    /// Initializes and returns a layout anchor object to specify a fractional offset value for the position of a panel.
+    /// Returns a layout anchor with the specified offset by a fractional value and reference guide for a panel.
     ///
     /// The offset value is a floating-point number in the range 0.0 to 1.0, where 0.0 represents the full content
     /// is displayed and 0.5 represents the half of content is displayed.
@@ -136,3 +140,62 @@ public extension FloatingPanelIntrinsicLayoutAnchor {
         }
     }
 }
+
+/// An object that defines how to settles a panel with a layout guide of a content view.
+@objc final public class FloatingPanelAdaptiveLayoutAnchor: NSObject, FloatingPanelLayoutAnchoring /*, NSCopying */ {
+
+    /// Returns a layout anchor with the specified offset by an absolute value, layout guide to display content and reference guide for a panel.
+    ///
+    /// The offset is an amount to offset a position of panel that displays the entire content of the specified guide from an edge of
+    /// the reference guide.  The edge refers to a panel positioning.
+    @objc public init(absoluteOffset offset: CGFloat, contentLayout: UILayoutGuide, referenceGuide: FloatingPanelLayoutReferenceGuide = .safeArea) {
+        self.offset = offset
+        self.contentLayoutGuide = contentLayout
+        self.referenceGuide = referenceGuide
+        self.isAbsolute = true
+
+    }
+
+    /// Returns a layout anchor with the specified offset by a fractional value, layout guide to display content and reference guide for a panel.
+    ///
+    /// The offset value is a floating-point number in the range 0.0 to 1.0, where 0.0 represents the full content
+    /// is displayed and 0.5 represents the half of content is displayed.
+    @objc public init(fractionalOffset offset: CGFloat, contentLayout: UILayoutGuide, referenceGuide: FloatingPanelLayoutReferenceGuide = .safeArea) {
+        self.offset = offset
+        self.contentLayoutGuide = contentLayout
+        self.referenceGuide = referenceGuide
+        self.isAbsolute = false
+    }
+    fileprivate let offset: CGFloat
+    fileprivate let isAbsolute: Bool
+    let contentLayoutGuide: UILayoutGuide
+    @objc public let referenceGuide: FloatingPanelLayoutReferenceGuide
+}
+
+public extension FloatingPanelAdaptiveLayoutAnchor {
+    func layoutConstraints(_ vc: FloatingPanelController, for position: FloatingPanelPosition) -> [NSLayoutConstraint] {
+        let layoutGuide = referenceGuide.layoutGuide(vc: vc)
+        let offsetAnchor: NSLayoutDimension
+        switch position {
+        case .top:
+            offsetAnchor = layoutGuide.topAnchor.anchorWithOffset(to: vc.surfaceView.bottomAnchor)
+        case .left:
+            offsetAnchor = layoutGuide.leftAnchor.anchorWithOffset(to: vc.surfaceView.rightAnchor)
+        case .bottom:
+            offsetAnchor = vc.surfaceView.topAnchor.anchorWithOffset(to: layoutGuide.bottomAnchor)
+        case .right:
+            offsetAnchor = vc.surfaceView.leftAnchor.anchorWithOffset(to: layoutGuide.rightAnchor)
+        }
+        if isAbsolute {
+            return [offsetAnchor.constraint(equalTo: position.mainDimensionAnchor(contentLayoutGuide), constant: -offset)]
+        } else {
+            return [offsetAnchor.constraint(equalTo: position.mainDimensionAnchor(contentLayoutGuide), multiplier: (1 - offset))]
+        }
+    }
+}
+
+extension FloatingPanelAdaptiveLayoutAnchor {
+    func distance(from dimension: CGFloat) -> CGFloat {
+        return isAbsolute ? offset : dimension * offset
+    }
+}

Sources/Logger.swift

@@ -3,6 +3,7 @@
 import Foundation
 import os.log
 
+// Must be a variable to use `hook` property in testing
 var log = {
     return Logger()
 }()
@@ -68,7 +69,7 @@ struct Logger {
 
         hook?(log, level)
 
-        os_log("%@", log: osLog, type: level.osLogType, log)
+        os_log("%{public}@", log: osLog, type: level.osLogType, log)
     }
 
     private func getPrettyFunction(_ function: String, _ file: String) -> String {

Sources/PassthroughView.swift

@@ -2,8 +2,8 @@
 
 import UIKit
 
-@objc(FloatingPanelPassThroughView)
-class PassThroughView: UIView {
+@objc(FloatingPanelPassthroughView)
+class PassthroughView: UIView {
     public weak var eventForwardingView: UIView?
     public override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
         let hitView = super.hitTest(point, with: event)

Sources/State.swift

@@ -4,7 +4,7 @@ import Foundation
 
 /// An object that represents the display state of a panel in a screen.
 @objc
-public class FloatingPanelState: NSObject, NSCopying, RawRepresentable {
+open class FloatingPanelState: NSObject, NSCopying, RawRepresentable {
     public typealias RawValue = String
 
     required public init?(rawValue: RawValue) {
@@ -13,6 +13,7 @@ public class FloatingPanelState: NSObject, NSCopying, RawRepresentable {
         super.init()
     }
 
+    @objc
     public init(rawValue: RawValue, order: Int) {
         self.rawValue = rawValue
         self.order = order
@@ -33,7 +34,7 @@ public class FloatingPanelState: NSObject, NSCopying, RawRepresentable {
     }
 
     public override var debugDescription: String {
-        return description
+        return "<FloatingPanel.FloatingPanelState: \(Unmanaged.passUnretained(self).toOpaque())>"
     }
 
     /// A panel state indicates the entire panel is shown.

Sources/SurfaceView.swift

@@ -50,6 +50,12 @@ public class SurfaceAppearance: NSObject {
     /// On iOS 10, they are not automatically masked because of a UIVisualEffectView issue. See https://forums.developer.apple.com/thread/50854
     public var cornerRadius: CGFloat = 0.0
 
+    /// Defines the curve used for rendering the rounded corners of the layer.
+    ///
+    /// Defaults to `.circular`.
+    @available(iOS 13.0, *)
+    public lazy var cornerCurve: CALayerCornerCurve = .circular
+
     /// An array of shadows used to create drop shadows underneath a surface view.
     public var shadows: [Shadow] = [Shadow()]
 
@@ -311,8 +317,8 @@ public class SurfaceView: UIView {
 
         containerView.backgroundColor = appearance.backgroundColor
 
-        updateShadow()
         updateCornerRadius()
+        updateShadow()
         updateBorder()
 
         grabberHandle.layer.cornerRadius = grabberHandleSize.height / 2
@@ -336,10 +342,9 @@ public class SurfaceView: UIView {
             shadowLayer.frame = layer.bounds
 
             let spread = shadow.spread
-            let shadowPath = UIBezierPath(roundedRect: containerView.frame.insetBy(dx: -spread,
-                                                                                   dy: -spread),
-                                          byRoundingCorners: [.allCorners],
-                                          cornerRadii: CGSize(width: appearance.cornerRadius, height: 0))
+            let shadowRect = containerView.frame.insetBy(dx: -spread, dy: -spread)
+            let shadowPath = UIBezierPath.path(roundedRect: shadowRect,
+                                               appearance: appearance)
             shadowLayer.shadowPath = shadowPath.cgPath
             shadowLayer.shadowColor = shadow.color.cgColor
             shadowLayer.shadowOffset = shadow.offset
@@ -348,16 +353,16 @@ public class SurfaceView: UIView {
             shadowLayer.shadowOpacity = shadow.opacity
 
             let mask = CAShapeLayer()
-            let path = UIBezierPath(roundedRect: containerView.frame,
-                                    byRoundingCorners: [.allCorners],
-                                    cornerRadii: CGSize(width: appearance.cornerRadius, height: 0))
+            let path = UIBezierPath.path(roundedRect: containerView.frame,
+                                         appearance: appearance)
             let size = window?.bounds.size ?? CGSize(width: 1000.0, height: 1000.0)
             path.append(UIBezierPath(rect: layer.bounds.insetBy(dx: -size.width,
                                                                 dy: -size.height)))
             mask.fillRule = .evenOdd
             mask.path = path.cgPath
             if #available(iOS 13.0, *) {
-                mask.cornerCurve = containerView.layer.cornerCurve
+                containerView.layer.cornerCurve = appearance.cornerCurve
+                mask.cornerCurve = appearance.cornerCurve
             }
             shadowLayer.mask = mask
         }

Sources/Transitioning.swift

@@ -61,7 +61,7 @@ class PresentationController: UIPresentationController {
         addFloatingPanel()
 
         // Forward touch events to the presenting view controller
-        (fpc.view as? PassThroughView)?.eventForwardingView = presentingViewController.view
+        (fpc.view as? PassthroughView)?.eventForwardingView = presentingViewController.view
     }
 
     @objc func handleBackdrop(tapGesture: UITapGestureRecognizer) {
@@ -86,19 +86,29 @@ class ModalPresentTransition: NSObject, UIViewControllerAnimatedTransitioning {
             let fpc = transitionContext?.viewController(forKey: .to) as? FloatingPanelController
         else { fatalError()}
 
-        let animator = fpc.delegate?.floatingPanel?(fpc, animatorForPresentingTo: fpc.layout.initialState)
-            ?? FloatingPanelDefaultBehavior().addPanelAnimator(fpc, to: fpc.layout.initialState)
+        let animator = fpc.animatorForPresenting(to: fpc.layout.initialState)
         return TimeInterval(animator.duration)
     }
 
-    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+    func interruptibleAnimator(using transitionContext: UIViewControllerContextTransitioning) -> UIViewImplicitlyAnimating {
         guard
             let fpc = transitionContext.viewController(forKey: .to) as? FloatingPanelController
         else { fatalError() }
 
-        fpc.show(animated: true) {
+        if let animator = fpc.transitionAnimator {
+            return animator
+        }
+
+        fpc.suspendTransitionAnimator(true)
+        fpc.show(animated: true) { [weak fpc] in
+            fpc?.suspendTransitionAnimator(false)
             transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
         }
+        return fpc.transitionAnimator!
+    }
+
+    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+        self.interruptibleAnimator(using: transitionContext).startAnimation()
     }
 }
 
@@ -108,19 +118,29 @@ class ModalDismissTransition: NSObject, UIViewControllerAnimatedTransitioning {
             let fpc = transitionContext?.viewController(forKey: .from) as? FloatingPanelController
         else { fatalError()}
 
-        let animator = fpc.delegate?.floatingPanel?(fpc, animatorForDismissingWith: .zero)
-            ?? FloatingPanelDefaultBehavior().removePanelAnimator(fpc, from: fpc.state, with: .zero)
+        let animator = fpc.animatorForDismissing(with: .zero)
         return TimeInterval(animator.duration)
     }
 
-    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+    func interruptibleAnimator(using transitionContext: UIViewControllerContextTransitioning) -> UIViewImplicitlyAnimating {
         guard
             let fpc = transitionContext.viewController(forKey: .from) as? FloatingPanelController
         else { fatalError() }
 
-        fpc.hide(animated: true) {
+        if let animator = fpc.transitionAnimator {
+            return animator
+        }
+
+        fpc.suspendTransitionAnimator(true)
+        fpc.hide(animated: true) { [weak fpc] in
+            fpc?.suspendTransitionAnimator(false)
             transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
         }
+        return fpc.transitionAnimator!
+    }
+
+    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+        self.interruptibleAnimator(using: transitionContext).startAnimation()
     }
 }
 

Sources/UIExtensions.swift

@@ -201,3 +201,70 @@ extension UIEdgeInsets {
         return self.top + self.bottom
     }
 }
+
+extension UIBezierPath {
+    static func path(roundedRect rect: CGRect, appearance: SurfaceAppearance) -> UIBezierPath {
+        let cornerRadius = appearance.cornerRadius;
+        if #available(iOS 13.0, *) {
+            if appearance.cornerCurve == .circular {
+                let path = UIBezierPath()
+                let start = CGPoint(x: rect.minX + cornerRadius, y: rect.minY)
+
+                path.move(to: start)
+
+                path.addLine(to: CGPoint(x: rect.maxX - cornerRadius, y: rect.minY))
+                if cornerRadius > 0 {
+                    path .addArc(withCenter: CGPoint(x: rect.maxX - cornerRadius,
+                                                     y: rect.minY + cornerRadius),
+                                 radius: cornerRadius,
+                                 startAngle: -0.5 * .pi,
+                                 endAngle: 0,
+                                 clockwise: true)
+                }
+
+                path.addLine(to: CGPoint(x: rect.maxX, y: rect.maxY - cornerRadius))
+
+                if cornerRadius > 0 {
+                    path.addArc(withCenter: CGPoint(x: rect.maxX - cornerRadius,
+                                                    y: rect.maxY - cornerRadius),
+                                radius: cornerRadius,
+                                startAngle: 0,
+                                endAngle: .pi * 0.5,
+                                clockwise: true)
+                }
+
+                path.addLine(to: CGPoint(x: rect.minX + cornerRadius, y: rect.maxY))
+
+                if cornerRadius > 0 {
+                    path.addArc(withCenter: CGPoint(x: rect.minX + cornerRadius,
+                                                    y: rect.maxY - cornerRadius),
+                                radius: cornerRadius,
+                                startAngle: .pi * 0.5,
+                                endAngle: .pi,
+                                clockwise: true)
+                }
+
+                path.addLine(to: CGPoint(x: rect.minX, y: rect.minY + cornerRadius))
+
+                if cornerRadius > 0 {
+                    path.addArc(withCenter: CGPoint(x: rect.minX + cornerRadius,
+                                                    y: rect.minY + cornerRadius),
+                                radius: cornerRadius,
+                                startAngle: .pi,
+                                endAngle: .pi * 1.5,
+                                clockwise: true)
+                }
+
+                path.addLine(to: start)
+
+                path.close()
+
+                return path
+            }
+        }
+        return UIBezierPath(roundedRect: rect,
+                            byRoundingCorners: [.allCorners],
+                            cornerRadii: CGSize(width: cornerRadius,
+                                                height: cornerRadius))
+    }
+}