Replace OTHER_SWIFT_FLAGS with SWIFT_UPCOMING_FEATURE_EXISTENTIAL_ANY

* Fixed existential any
* Added upcoming feature flag

.circleci/config.yml

@@ -1,27 +1,6 @@
 version: 2.1
 
 jobs:
-  build-swift_5_7:
-    macos:
-      xcode: 13.4.1
-    steps:
-      - checkout
-      - run: xcodebuild -scheme FloatingPanel -workspace FloatingPanel.xcworkspace SWIFT_VERSION=5.7 clean build
-
-  build-swiftpm_ios15_7:
-    macos:
-      xcode: 13.4.1
-    steps:
-      - checkout
-      - run: swift build -Xswiftc "-sdk" -Xswiftc "`xcrun --sdk iphonesimulator --show-sdk-path`" -Xswiftc "-target" -Xswiftc "x86_64-apple-ios15.7-simulator"
-      - run: swift build -Xswiftc "-sdk" -Xswiftc "`xcrun --sdk iphonesimulator --show-sdk-path`" -Xswiftc "-target" -Xswiftc "arm64-apple-ios15.7-simulator"
-
-  test-ios15_5-iPhone_13_Pro:
-    macos:
-      xcode: 13.4.1
-    steps:
-      - checkout
-      - run: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=15.5,name=iPhone 13 Pro'
   test-ios14_5-iPhone_12_Pro:
     macos:
       xcode: 13.4.1
@@ -29,15 +8,7 @@ jobs:
       - checkout
       - run: xcodebuild clean test -scheme FloatingPanel -workspace FloatingPanel.xcworkspace -destination 'platform=iOS Simulator,OS=14.5,name=iPhone 12 Pro'
 
-
 workflows:
   test: 
     jobs:
-      - build-swift_5_7:
-          name: build (5.7, 13.4.1)
-      - build-swiftpm_ios15_7:
-          name: swiftpm ({x86_64,arm64}-apple-ios15.5-simulator, 13.4.1)
-      - test-ios14_5-iPhone_12_Pro:
-          name: test (15.5, 13.4.1, iPhone 12 Pro)
-      - test-ios15_5-iPhone_13_Pro:
-          name: test (14.5, 13.4.1, iPhone 13 Pro)
+      - test-ios14_5-iPhone_12_Pro

.github/workflows/ci.yml

@@ -18,9 +18,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - swift: "5"
-            xcode: "16.2"
-            runs-on: macos-15
           - swift: "5.10"
             xcode: "15.4"
             runs-on: macos-14
@@ -30,6 +27,15 @@ jobs:
           - swift: "5.8"
             xcode: "14.3.1"
             runs-on: macos-13
+          - swift: "5.7"
+            xcode: "14.1"
+            runs-on: macos-12
+          - swift: "5.6"
+            xcode: "13.4.1"
+            runs-on: macos-12
+          - swift: "5.5"
+            xcode: "13.2.1"
+            runs-on: macos-12
     steps:
       - uses: actions/checkout@v4
       - name: Building in Swift ${{ matrix.swift }}
@@ -43,11 +49,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - os: "18.2"
-            xcode: "16.2"
-            sim: "iPhone 16 Pro"
-            parallel: NO  # Stop random test job failures
-            runs-on: macos-15
           - os: "17.5"
             xcode: "15.4"
             sim: "iPhone 15 Pro"
@@ -58,6 +59,11 @@ jobs:
             sim: "iPhone 14 Pro"
             parallel: NO  # Stop random test job failures
             runs-on: macos-13
+          - os: "15.5"
+            xcode: "13.4.1"
+            sim: "iPhone 13 Pro"
+            parallel: NO  # Stop random test job failures
+            runs-on: macos-12
     steps:
     - uses: actions/checkout@v4
     - name: Testing in iOS ${{ matrix.os }}
@@ -70,9 +76,9 @@ jobs:
     timeout-minutes: 20
 
   example:
-    runs-on: macos-15
+    runs-on: macos-14
     env:
-      DEVELOPER_DIR: /Applications/Xcode_16.2.app/Contents/Developer
+      DEVELOPER_DIR: /Applications/Xcode_15.4.app/Contents/Developer
     strategy:
       fail-fast: false
       matrix:
@@ -84,7 +90,6 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - name: Building ${{ matrix.example }}
-      # Need to use iphonesimulator18.1 because randomly 18.2<DVTBuildVersion 22C146> isn't available.
       run: |
         xcodebuild clean build \
           -workspace FloatingPanel.xcworkspace \
@@ -92,32 +97,22 @@ jobs:
           -sdk iphonesimulator
 
   swiftpm:
-    runs-on: macos-15
+    runs-on: macos-14
     env:
-      DEVELOPER_DIR: /Applications/Xcode_${{ matrix.xcode }}.app/Contents/Developer
+      DEVELOPER_DIR: /Applications/Xcode_15.4.app/Contents/Developer
     strategy:
       fail-fast: false
       matrix:
-        xcode: ["16.2", "15.4"]
         platform: [iphoneos, iphonesimulator]
         arch: [x86_64, arm64]
         exclude:
           - platform: iphoneos
             arch: x86_64
         include:
-          # 18.2
-          - platform: iphoneos
-            xcode: "16.2"
-            sys: "ios18.2"
-          - platform: iphonesimulator
-            xcode: "16.2"
-            sys: "ios18.2-simulator"
           # 17.2
           - platform: iphoneos
-            xcode: "15.4"
             sys: "ios17.2"
           - platform: iphonesimulator
-            xcode: "15.4"
             sys: "ios17.2-simulator"
     steps:
     - uses: actions/checkout@v4
@@ -142,6 +137,13 @@ jobs:
           - target: "arm64-apple-ios16.4-simulator"
             xcode: "14.3.1"
             runs-on: macos-13
+          # 15.7
+          - target: "x86_64-apple-ios15.7-simulator"
+            xcode: "14.1"
+            runs-on: macos-12
+          - target: "arm64-apple-ios15.7-simulator"
+            xcode: "14.1"
+            runs-on: macos-12
     steps:
     - uses: actions/checkout@v4
     - name: "Swift Package Manager build"
@@ -151,12 +153,12 @@ jobs:
           -Xswiftc "-target" -Xswiftc "${{ matrix.target }}"
 
   cocoapods:
-    runs-on: macos-15
+    runs-on: macos-14
     env:
-      DEVELOPER_DIR: /Applications/Xcode_16.2.app/Contents/Developer
+      DEVELOPER_DIR: /Applications/Xcode_15.4.app/Contents/Developer
     steps:
     - uses: actions/checkout@v4
     - name: "CocoaPods: pod lib lint"
-      run: pod lib lint --allow-warnings --verbose
+      run: pod lib lint --allow-warnings
     - name: "CocoaPods: pod spec lint"
-      run: pod spec lint --allow-warnings --verbose
+      run: pod spec lint --allow-warnings

Examples/Samples/Sources/UseCases/UseCaseController.swift

@@ -3,6 +3,7 @@
 import UIKit
 import FloatingPanel
 
+@MainActor
 final class UseCaseController: NSObject {
     unowned let mainVC: MainViewController
     private(set) var useCase: UseCase
@@ -202,10 +203,10 @@ extension UseCaseController {
             fpc.set(contentViewController: contentVC)
             fpc.delegate = self
 
-            let appearance = SurfaceAppearance()
-            appearance.cornerRadius = 38.5
-            appearance.shadows = []
-            fpc.surfaceView.appearance = appearance
+            let apprearance = SurfaceAppearance()
+            apprearance.cornerRadius = 38.5
+            apprearance.shadows = []
+            fpc.surfaceView.appearance = apprearance
             fpc.isRemovalInteractionEnabled = true
 
             let mvc = UIViewController()

FloatingPanel.podspec

@@ -1,7 +1,7 @@
 Pod::Spec.new do |s|
 
   s.name                = "FloatingPanel"
-  s.version             = "2.8.7"
+  s.version             = "2.8.4"
   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.
@@ -9,7 +9,7 @@ The new interface displays the related contents and utilities in parallel as a u
                    DESC
   s.homepage            = "https://github.com/scenee/FloatingPanel"
   s.author              = "Shin Yamamoto"
-  s.social_media_url    = "https://x.com/scenee"
+  s.social_media_url    = "https://twitter.com/scenee"
 
   s.platform            = :ios, "11.0"
   s.source              = { :git => "https://github.com/scenee/FloatingPanel.git", :tag => s.version.to_s }

FloatingPanel.xcodeproj/project.pbxproj

@@ -462,7 +462,7 @@
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				INFOPLIST_FILE = Sources/Info.plist;
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
-				IPHONEOS_DEPLOYMENT_TARGET = 11.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -475,6 +475,19 @@
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
 				SWIFT_COMPILATION_MODE = wholemodule;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_STRICT_CONCURRENCY = complete;
+				SWIFT_UPCOMING_FEATURE_CONCISE_MAGIC_FILE = YES;
+				SWIFT_UPCOMING_FEATURE_DEPRECATE_APPLICATION_MAIN = YES;
+				SWIFT_UPCOMING_FEATURE_DISABLE_OUTWARD_ACTOR_ISOLATION = YES;
+				SWIFT_UPCOMING_FEATURE_EXISTENTIAL_ANY = YES;
+				SWIFT_UPCOMING_FEATURE_FORWARD_TRAILING_CLOSURES = YES;
+				SWIFT_UPCOMING_FEATURE_GLOBAL_CONCURRENCY = YES;
+				SWIFT_UPCOMING_FEATURE_IMPLICIT_OPEN_EXISTENTIALS = YES;
+				SWIFT_UPCOMING_FEATURE_IMPORT_OBJC_FORWARD_DECLS = YES;
+				SWIFT_UPCOMING_FEATURE_INFER_SENDABLE_FROM_CAPTURES = YES;
+				SWIFT_UPCOMING_FEATURE_INTERNAL_IMPORTS_BY_DEFAULT = YES;
+				SWIFT_UPCOMING_FEATURE_ISOLATED_DEFAULT_VALUES = YES;
+				SWIFT_UPCOMING_FEATURE_REGION_BASED_ISOLATION = YES;
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
@@ -494,7 +507,7 @@
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				INFOPLIST_FILE = Sources/Info.plist;
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
-				IPHONEOS_DEPLOYMENT_TARGET = 11.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -505,6 +518,19 @@
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SKIP_INSTALL = YES;
 				SWIFT_COMPILATION_MODE = wholemodule;
+				SWIFT_STRICT_CONCURRENCY = complete;
+				SWIFT_UPCOMING_FEATURE_CONCISE_MAGIC_FILE = YES;
+				SWIFT_UPCOMING_FEATURE_DEPRECATE_APPLICATION_MAIN = YES;
+				SWIFT_UPCOMING_FEATURE_DISABLE_OUTWARD_ACTOR_ISOLATION = YES;
+				SWIFT_UPCOMING_FEATURE_EXISTENTIAL_ANY = YES;
+				SWIFT_UPCOMING_FEATURE_FORWARD_TRAILING_CLOSURES = YES;
+				SWIFT_UPCOMING_FEATURE_GLOBAL_CONCURRENCY = YES;
+				SWIFT_UPCOMING_FEATURE_IMPLICIT_OPEN_EXISTENTIALS = YES;
+				SWIFT_UPCOMING_FEATURE_IMPORT_OBJC_FORWARD_DECLS = YES;
+				SWIFT_UPCOMING_FEATURE_INFER_SENDABLE_FROM_CAPTURES = YES;
+				SWIFT_UPCOMING_FEATURE_INTERNAL_IMPORTS_BY_DEFAULT = YES;
+				SWIFT_UPCOMING_FEATURE_ISOLATED_DEFAULT_VALUES = YES;
+				SWIFT_UPCOMING_FEATURE_REGION_BASED_ISOLATION = YES;
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
@@ -631,7 +657,7 @@
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				INFOPLIST_FILE = Sources/Info.plist;
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
-				IPHONEOS_DEPLOYMENT_TARGET = 11.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -644,6 +670,19 @@
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = "TEST DEBUG FP_LOG";
 				SWIFT_COMPILATION_MODE = singlefile;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_STRICT_CONCURRENCY = complete;
+				SWIFT_UPCOMING_FEATURE_CONCISE_MAGIC_FILE = YES;
+				SWIFT_UPCOMING_FEATURE_DEPRECATE_APPLICATION_MAIN = YES;
+				SWIFT_UPCOMING_FEATURE_DISABLE_OUTWARD_ACTOR_ISOLATION = YES;
+				SWIFT_UPCOMING_FEATURE_EXISTENTIAL_ANY = YES;
+				SWIFT_UPCOMING_FEATURE_FORWARD_TRAILING_CLOSURES = YES;
+				SWIFT_UPCOMING_FEATURE_GLOBAL_CONCURRENCY = YES;
+				SWIFT_UPCOMING_FEATURE_IMPLICIT_OPEN_EXISTENTIALS = YES;
+				SWIFT_UPCOMING_FEATURE_IMPORT_OBJC_FORWARD_DECLS = YES;
+				SWIFT_UPCOMING_FEATURE_INFER_SENDABLE_FROM_CAPTURES = YES;
+				SWIFT_UPCOMING_FEATURE_INTERNAL_IMPORTS_BY_DEFAULT = YES;
+				SWIFT_UPCOMING_FEATURE_ISOLATED_DEFAULT_VALUES = YES;
+				SWIFT_UPCOMING_FEATURE_REGION_BASED_ISOLATION = YES;
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};

README.md

@@ -8,7 +8,7 @@
 FloatingPanel is a simple and easy-to-use UI component designed for a user interface featured in Apple Maps, Shortcuts and Stocks app.
 The user interface displays related content and utilities alongside the main content.
 
-Please see also [the API reference@SPI](https://swiftpackageindex.com/scenee/FloatingPanel/2.8.7/documentation/floatingpanel) for more details.
+Please see also [the API reference@SPI](https://swiftpackageindex.com/scenee/FloatingPanel/2.8.4/documentation/floatingpanel) for more details.
 
 ![Maps](https://github.com/SCENEE/FloatingPanel/blob/master/assets/maps.gif)
 ![Stocks](https://github.com/SCENEE/FloatingPanel/blob/master/assets/stocks.gif)

Sources/Behavior.swift

@@ -86,9 +86,9 @@ open class FloatingPanelDefaultBehavior: FloatingPanelBehavior {
 
 class BehaviorAdapter {
     unowned let vc: FloatingPanelController
-    fileprivate var behavior: FloatingPanelBehavior
+    fileprivate var behavior: any FloatingPanelBehavior
 
-    init(vc: FloatingPanelController, behavior: FloatingPanelBehavior) {
+    init(vc: FloatingPanelController, behavior: any FloatingPanelBehavior) {
         self.vc = vc
         self.behavior = behavior
     }
@@ -123,7 +123,7 @@ class BehaviorAdapter {
 }
 
 extension FloatingPanelController {
-    var _behavior: FloatingPanelBehavior {
+    var _behavior: any FloatingPanelBehavior {
         get { floatingPanel.behaviorAdapter.behavior }
         set { floatingPanel.behaviorAdapter.behavior = newValue}
     }

Sources/Controller.swift

@@ -6,14 +6,15 @@ import os.log
 /// 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.
+@MainActor
 @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
+    func floatingPanel(_ fpc: FloatingPanelController, layoutFor newCollection: UITraitCollection) -> any FloatingPanelLayout
 
     /// Returns a FloatingPanelLayout object. If you use the default one, you can use a `FloatingPanelBottomLayout` object.
     @objc(floatingPanel:layoutForSize:) optional
-    func floatingPanel(_ fpc: FloatingPanelController, layoutFor size: CGSize) -> FloatingPanelLayout
+    func floatingPanel(_ fpc: FloatingPanelController, layoutFor size: CGSize) -> any FloatingPanelLayout
 
     /// Returns a UIViewPropertyAnimator object to add/present the  panel to a position.
     ///
@@ -150,7 +151,7 @@ open class FloatingPanelController: UIViewController {
 
     /// The delegate of a panel controller object.
     @objc
-    public weak var delegate: FloatingPanelControllerDelegate?{
+    public weak var delegate: (any FloatingPanelControllerDelegate)?{
         didSet{
             didUpdateDelegate()
         }
@@ -198,7 +199,7 @@ open class FloatingPanelController: UIViewController {
     /// You need to call ``invalidateLayout()`` if you want to apply a new layout object into the panel
     /// immediately.
     @objc
-    public var layout: FloatingPanelLayout {
+    public var layout: any FloatingPanelLayout {
         get { _layout }
         set {
             _layout = newValue
@@ -211,7 +212,7 @@ open class FloatingPanelController: UIViewController {
 
     /// The behavior object that the controller manages
     @objc
-    public var behavior: FloatingPanelBehavior {
+    public var behavior: any FloatingPanelBehavior {
         get { _behavior }
         set {
             _behavior = newValue
@@ -282,7 +283,7 @@ open class FloatingPanelController: UIViewController {
 
     /// Initialize a newly created panel controller.
     @objc
-    public init(delegate: FloatingPanelControllerDelegate? = nil) {
+    public init(delegate: (any FloatingPanelControllerDelegate)? = nil) {
         super.init(nibName: nil, bundle: nil)
         self.delegate = delegate
         setUp()
@@ -294,7 +295,7 @@ open class FloatingPanelController: UIViewController {
         modalPresentationStyle = .custom
         transitioningDelegate = modalTransition
 
-        let initialLayout: FloatingPanelLayout
+        let initialLayout: any FloatingPanelLayout
         if let layout = delegate?.floatingPanel?(self, layoutFor: traitCollection) {
             initialLayout = layout
         } else {
@@ -344,7 +345,7 @@ open class FloatingPanelController: UIViewController {
         floatingPanel.adjustScrollContentInsetIfNeeded()
     }
 
-    open override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
+    open override func viewWillTransition(to size: CGSize, with coordinator: any UIViewControllerTransitionCoordinator) {
         super.viewWillTransition(to: size, with: coordinator)
 
         if self.view.bounds.size == size {
@@ -363,7 +364,7 @@ open class FloatingPanelController: UIViewController {
         }
     }
 
-    open override func willTransition(to newCollection: UITraitCollection, with coordinator: UIViewControllerTransitionCoordinator) {
+    open override func willTransition(to newCollection: UITraitCollection, with coordinator: any UIViewControllerTransitionCoordinator) {
         super.willTransition(to: newCollection, with: coordinator)
 
         if shouldUpdateLayout(from: traitCollection, to: newCollection) == false {
@@ -483,16 +484,18 @@ open class FloatingPanelController: UIViewController {
         // 2. The safe area top inset can be variable on the large title navigation bar(iOS11+).
         // That's why it needs the observation to keep `adjustedContentInsets` correct.
         safeAreaInsetsObservation = self.view.observe(\.safeAreaInsets, options: [.initial, .new, .old]) { [weak self] (_, change) in
-            // Use `self.view.safeAreaInsets` because `change.newValue` can be nil in particular case when
-            // is reported in https://github.com/SCENEE/FloatingPanel/issues/330
-            guard let self = self, change.oldValue != self.view.safeAreaInsets else { return }
+            MainActor.assumeIsolated {
+                // Use `self.view.safeAreaInsets` because `change.newValue` can be nil in particular case when
+                // is reported in https://github.com/SCENEE/FloatingPanel/issues/330
+                guard let self = self, change.oldValue != self.view.safeAreaInsets else { return }
 
-            // Sometimes the bounding rectangle of the controlled view becomes invalid when the screen is rotated.
-            // This results in its safeAreaInsets change. In that case, `self.update(safeAreaInsets:)` leads
-            // an unsatisfied constraints error. So this method should not be called with those bounds.
-            guard self.view.bounds.height > 0 && self.view.bounds.width > 0 else { return }
+                // Sometimes the bounding rectangle of the controlled view becomes invalid when the screen is rotated.
+                // This results in its safeAreaInsets change. In that case, `self.update(safeAreaInsets:)` leads
+                // an unsatisfied constraints error. So this method should not be called with those bounds.
+                guard self.view.bounds.height > 0 && self.view.bounds.width > 0 else { return }
 
-            self.update(safeAreaInsets: self.view.safeAreaInsets)
+                self.update(safeAreaInsets: self.view.safeAreaInsets)
+            }
         }
 
         move(to: floatingPanel.layoutAdapter.initialState,
@@ -729,7 +732,7 @@ extension FloatingPanelController {
 
 // MARK: - Swizzling
 
-private var originalDismissImp: IMP?
+@MainActor private var originalDismissImp: IMP?
 private typealias DismissFunction = @convention(c) (AnyObject, Selector, Bool, (() -> Void)?) -> Void
 extension FloatingPanelController {
     private static let dismissSwizzling: Void = {

Sources/Core.swift

@@ -3,7 +3,6 @@
 import UIKit
 import os.log
 
-///
 /// The presentation model of FloatingPanel
 ///
 class Core: NSObject, UIGestureRecognizerDelegate {
@@ -71,7 +70,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
     var removalVector: CGVector = .zero
 
     // Scroll handling
-    private var initialScrollOffset: CGPoint?
+    private var initialScrollOffset: CGPoint = .zero
     private var scrollBounce = false
     private var scrollIndictorVisible = false
     private var scrollBounceThreshold: CGFloat = -30.0
@@ -79,7 +78,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
 
     // MARK: - Interface
 
-    init(_ vc: FloatingPanelController, layout: FloatingPanelLayout, behavior: FloatingPanelBehavior) {
+    init(_ vc: FloatingPanelController, layout: any FloatingPanelLayout, behavior: any FloatingPanelBehavior) {
         ownerVC = vc
 
         surfaceView = SurfaceView()
@@ -114,8 +113,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
     }
 
     deinit {
-        // Release `NumericSpringAnimator.displayLink` from the run loop.
-        self.moveAnimator?.stopAnimation(false)
+        moveAnimator?.stopAnimation(false)
     }
 
     func move(to: FloatingPanelState, animated: Bool, completion: (() -> Void)? = nil) {
@@ -411,7 +409,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
 
             if insideMostExpandedAnchor {
                 // Prevent scrolling if needed
-                if isScrollable(state: state), let initialScrollOffset = initialScrollOffset {
+                if isScrollable(state: state) {
                     if interactionInProgress {
                         os_log(msg, log: devLog, type: .debug, "settle offset -- \(value(of: initialScrollOffset))")
                         // Return content offset to initial offset to prevent scrolling
@@ -429,7 +427,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                             stopScrolling(at: initialScrollOffset)
                         }
                     }
-                } else if let initialScrollOffset = initialScrollOffset {
+                } else {
                     // Return content offset to initial offset to prevent scrolling
                     stopScrolling(at: initialScrollOffset)
                 }
@@ -471,8 +469,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                     }
                     if isScrollable(state: state) {
                         // Adjust a small gap of the scroll offset just after swiping down starts in the grabber area.
-                        if surfaceView.grabberAreaContains(location), surfaceView.grabberAreaContains(initialLocation),
-                            let initialScrollOffset = initialScrollOffset {
+                        if surfaceView.grabberAreaContains(location), surfaceView.grabberAreaContains(initialLocation) {
                             stopScrolling(at: initialScrollOffset)
                         }
                     }
@@ -500,8 +497,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                             }
                         }
                         // Adjust a small gap of the scroll offset just before swiping down starts in the grabber area,
-                        if surfaceView.grabberAreaContains(location), surfaceView.grabberAreaContains(initialLocation),
-                            let initialScrollOffset = initialScrollOffset {
+                        if surfaceView.grabberAreaContains(location), surfaceView.grabberAreaContains(initialLocation) {
                             stopScrolling(at: initialScrollOffset)
                         }
                     }
@@ -610,7 +606,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         guard
             isScrollable(state: state),  // When not top most(i.e. .full), don't scroll.
             interactionInProgress == false,  // When interaction already in progress, don't scroll.
-            abs(layoutAdapter.offset(from: state)) < 1, // Indistinguishably close to an anchor point.
+            0 == layoutAdapter.offset(from: state),
             !surfaceView.grabberAreaContains(initialLocation)  // When the initial point is within grabber area, don't scroll
         else {
             return false
@@ -849,7 +845,7 @@ class Core: NSObject, UIGestureRecognizerDelegate {
             } else {
                 initialScrollOffset = scrollView.contentOffset
             }
-            os_log(msg, log: devLog, type: .debug, "initial scroll offset -- \(optional: initialScrollOffset)")
+            os_log(msg, log: devLog, type: .debug, "initial scroll offset -- \(initialScrollOffset)")
         }
 
         initialTranslation = translation
@@ -896,6 +892,17 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         return true
     }
 
+    func endWithoutAttraction(_ target: FloatingPanelState) {
+        self.state = target
+        self.updateLayout(to: target)
+        self.unlockScrollView()
+        // The `floatingPanelDidEndDragging(_:willAttract:)` must be called after the state property changes.
+        // This allows library users to get the correct state in the delegate method.
+        if let vc = ownerVC {
+            vc.delegate?.floatingPanelDidEndDragging?(vc, willAttract: false)
+        }
+    }
+
     private func startAttraction(to state: FloatingPanelState, with velocity: CGPoint, completion: @escaping (() -> Void)) {
         os_log(msg, log: devLog, type: .debug, "startAnimation to \(state) -- velocity = \(value(of: velocity))")
         guard let vc = ownerVC else { return }
@@ -925,8 +932,8 @@ class Core: NSObject, UIGestureRecognizerDelegate {
                 self.backdropView.alpha = self.getBackdropAlpha(at: current, with: translation)
 
                 // Pin the offset of the tracking scroll view while moving by this animator
-                if let scrollView = self.scrollView, let initialScrollOffset = self.initialScrollOffset {
-                    self.stopScrolling(at: initialScrollOffset)
+                if let scrollView = self.scrollView {
+                    self.stopScrolling(at: self.initialScrollOffset)
                     os_log(msg, log: devLog, type: .debug, "move -- pinning scroll offset = \(scrollView.contentOffset)")
                 }
 
@@ -950,12 +957,6 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         self.isAttracting = false
         self.moveAnimator = nil
 
-        // We need to reset `initialScrollOffset` because the scroll offset can become unexpected
-        // under the following circumstances:
-        // 1. The scroll offset changes while the panel does not move.
-        // 2. The panel is then moved using `move(to:animate:completion:)`.
-        self.initialScrollOffset = nil
-
         if let vc = ownerVC {
             vc.delegate?.floatingPanelDidEndAttracting?(vc)
         }
@@ -978,20 +979,6 @@ class Core: NSObject, UIGestureRecognizerDelegate {
         }
     }
 
-    func endWithoutAttraction(_ target: FloatingPanelState) {
-        // See comments in `endAttraction`
-        self.initialScrollOffset = nil
-
-        self.state = target
-        self.updateLayout(to: target)
-        self.unlockScrollView()
-        // The `floatingPanelDidEndDragging(_:willAttract:)` must be called after the state property changes.
-        // This allows library users to get the correct state in the delegate method.
-        if let vc = ownerVC {
-            vc.delegate?.floatingPanelDidEndDragging?(vc, willAttract: false)
-        }
-    }
-
     func value(of point: CGPoint) -> CGFloat {
         return layoutAdapter.position.mainLocation(point)
     }
@@ -1258,7 +1245,7 @@ public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
     ///
     /// - Note: The delegate is used by FloatingPanel itself. If you set your own delegate object, an
     /// exception is raised. If you want to handle the methods of UIGestureRecognizerDelegate, you can use `delegateProxy`.
-    public override weak var delegate: UIGestureRecognizerDelegate? {
+    public override weak var delegate: (any UIGestureRecognizerDelegate)? {
         get {
             return super.delegate
         }
@@ -1279,7 +1266,7 @@ public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
     /// The default object implementing a set methods of the delegate of the gesture recognizer.
     ///
     /// Use this property with ``delegateProxy`` when you need to use the default gesture behaviors in a proxy implementation.
-    public var delegateOrigin: UIGestureRecognizerDelegate {
+    public var delegateOrigin: any UIGestureRecognizerDelegate {
         return floatingPanel
     }
 
@@ -1287,7 +1274,7 @@ public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
     ///
     /// `UIGestureRecognizerDelegate` methods implementing by this object are called instead of the default delegate,
     ///  ``delegateOrigin``.
-    public weak var delegateProxy: UIGestureRecognizerDelegate? {
+    public weak var delegateProxy: (any UIGestureRecognizerDelegate)? {
         didSet {
             self.delegate = floatingPanel?.panGestureDelegateRouter // Update the cached IMP
         }
@@ -1320,7 +1307,7 @@ public final class FloatingPanelPanGestureRecognizer: UIPanGestureRecognizer {
 
 // MARK: - Animator
 
-private class NumericSpringAnimator: NSObject {
+private final class NumericSpringAnimator: NSObject,  @unchecked Sendable  {
     struct Data {
         let value: CGFloat
         let velocity: CGFloat

Sources/Extensions.swift

@@ -36,6 +36,7 @@ extension CGPoint {
 
 // MARK: - UIKit
 
+@MainActor
 protocol LayoutGuideProvider {
     var topAnchor: NSLayoutYAxisAnchor { get }
     var leftAnchor: NSLayoutXAxisAnchor { get }

Sources/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.8.7</string>
+	<string>2.8.4</string>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
 </dict>

Sources/Layout.swift

@@ -4,6 +4,7 @@ import UIKit
 import os.log
 
 /// An interface for generating layout information for a panel.
+@MainActor
 @objc public protocol FloatingPanelLayout {
     /// Returns the position of a panel in a `FloatingPanelController` view .
     @objc var position: FloatingPanelPosition { get }
@@ -12,7 +13,7 @@ import os.log
     @objc var initialState: FloatingPanelState { get }
 
     /// Returns the layout anchors to specify the snapping locations for each state.
-    @objc var anchors: [FloatingPanelState: FloatingPanelLayoutAnchoring] { get }
+    @objc var anchors: [FloatingPanelState: any FloatingPanelLayoutAnchoring] { get }
 
     /// Returns layout constraints to determine the cross dimension of a panel.
     @objc optional func prepareLayout(surfaceView: UIView, in view: UIView) -> [NSLayoutConstraint]
@@ -31,7 +32,7 @@ open class FloatingPanelBottomLayout: NSObject, FloatingPanelLayout {
         return .half
     }
 
-    open var anchors: [FloatingPanelState: FloatingPanelLayoutAnchoring]  {
+    open var anchors: [FloatingPanelState: any FloatingPanelLayoutAnchoring]  {
         return [
             .full: FloatingPanelLayoutAnchor(absoluteInset: 18.0, edge: .top, referenceGuide: .safeArea),
             .half: FloatingPanelLayoutAnchor(fractionalInset: 0.5, edge: .bottom, referenceGuide: .safeArea),
@@ -60,11 +61,12 @@ struct LayoutSegment {
     let upper: FloatingPanelState?
 }
 
+@MainActor
 class LayoutAdapter {
     private unowned var vc: FloatingPanelController
     private let defaultLayout = FloatingPanelBottomLayout()
 
-    fileprivate var layout: FloatingPanelLayout {
+    fileprivate var layout: any FloatingPanelLayout {
         didSet {
             surfaceView.position = position
         }
@@ -287,7 +289,7 @@ class LayoutAdapter {
         return offset.rounded(by: surfaceView.fp_displayScale)
     }
 
-    private var hiddenAnchor: FloatingPanelLayoutAnchoring {
+    private var hiddenAnchor: any FloatingPanelLayoutAnchoring {
         switch position {
         case .top:
             return FloatingPanelLayoutAnchor(absoluteInset: -100, edge: .top, referenceGuide: .superview)
@@ -300,7 +302,7 @@ class LayoutAdapter {
         }
     }
 
-    init(vc: FloatingPanelController, layout: FloatingPanelLayout) {
+    init(vc: FloatingPanelController, layout: any FloatingPanelLayout) {
         self.vc = vc
         self.layout = layout
     }
@@ -404,7 +406,7 @@ class LayoutAdapter {
         }
     }
 
-    private func referenceEdge(of anchor: FloatingPanelLayoutAnchoring) -> FloatingPanelReferenceEdge {
+    private func referenceEdge(of anchor: any FloatingPanelLayoutAnchoring) -> FloatingPanelReferenceEdge {
         switch anchor {
         case is FloatingPanelIntrinsicLayoutAnchor,
             is FloatingPanelAdaptiveLayoutAnchor:
@@ -546,7 +548,7 @@ class LayoutAdapter {
         NSLayoutConstraint.deactivate(constraint: interactionConstraint)
         interactionConstraint = nil
 
-        let layoutGuideProvider: LayoutGuideProvider
+        let layoutGuideProvider: any LayoutGuideProvider
         switch anchor.referenceGuide {
         case .safeArea:
             layoutGuideProvider = vc.view.safeAreaLayoutGuide
@@ -854,7 +856,7 @@ extension LayoutAdapter {
 }
 
 extension FloatingPanelController {
-    var _layout: FloatingPanelLayout {
+    var _layout: any FloatingPanelLayout {
         get {
             floatingPanel.layoutAdapter.layout
         }

Sources/LayoutAnchoring.swift

@@ -3,6 +3,7 @@
 import UIKit
 
 /// An interface for implementing custom layout anchor objects.
+@MainActor
 @objc public protocol FloatingPanelLayoutAnchoring {
     var referenceGuide: FloatingPanelLayoutReferenceGuide { get }
     func layoutConstraints(_ fpc: FloatingPanelController, for position: FloatingPanelPosition) -> [NSLayoutConstraint]
@@ -17,7 +18,7 @@ import UIKit
     /// positioning.
     ///
     /// - Parameters:
-    ///     - absoluteInset: An absolute distance to attach the panel from the specified edge.
+    ///     - absoluteInset: An absolute offset to attach the panel from the edge.
     ///     - edge: Specify the edge of ``FloatingPanelController``'s view. This is the staring point of the offset.
     ///     - referenceGuide: The rectangular area to lay out the content. If it's set to `.safeArea`, the panel content lays out inside the safe area of its ``FloatingPanelController``'s view.
     @objc public init(absoluteInset: CGFloat, edge: FloatingPanelReferenceEdge, referenceGuide: FloatingPanelLayoutReferenceGuide) {
@@ -34,7 +35,7 @@ import UIKit
     /// 1.0 represents a distance to the opposite edge.
     ///
     /// - Parameters:
-    ///     - fractionalInset: A fractional value of the size of ``FloatingPanelController``'s view to attach the panel from the specified edge.
+    ///     - fractionalInset: A fractional value of the size of ``FloatingPanelController``'s view to attach the panel from the edge.
     ///     - edge: Specify the edge of ``FloatingPanelController``'s view. This is the staring point of the offset.
     ///     - referenceGuide: The rectangular area to lay out the content. If it's set to `.safeArea`, the panel content lays out inside the safe area of its ``FloatingPanelController``'s view.
     @objc public init(fractionalInset: CGFloat, edge: FloatingPanelReferenceEdge, referenceGuide: FloatingPanelLayoutReferenceGuide) {
@@ -65,7 +66,7 @@ public extension FloatingPanelLayoutAnchor {
         }
     }
 
-    private func layoutConstraints(_ layoutGuide: LayoutGuideProvider, for edgeAnchor: NSLayoutYAxisAnchor) -> [NSLayoutConstraint] {
+    private func layoutConstraints(_ layoutGuide: any LayoutGuideProvider, for edgeAnchor: NSLayoutYAxisAnchor) -> [NSLayoutConstraint] {
         switch referenceEdge {
         case .top:
             if isAbsolute {
@@ -84,7 +85,7 @@ public extension FloatingPanelLayoutAnchor {
         }
     }
 
-    private func layoutConstraints(_ layoutGuide: LayoutGuideProvider, for edgeAnchor: NSLayoutXAxisAnchor) -> [NSLayoutConstraint] {
+    private func layoutConstraints(_ layoutGuide: any LayoutGuideProvider, for edgeAnchor: NSLayoutXAxisAnchor) -> [NSLayoutConstraint] {
         switch referenceEdge {
         case .left:
             if isAbsolute {

Sources/LayoutProperties.swift

@@ -3,6 +3,7 @@
 import UIKit
 
 /// Constants that specify the edge of the container of a panel.
+@MainActor
 @objc public enum FloatingPanelReferenceEdge: Int {
     case top
     case left
@@ -28,13 +29,14 @@ extension FloatingPanelReferenceEdge {
 }
 
 /// A representation to specify a rectangular area to lay out a panel.
+@MainActor
 @objc public enum FloatingPanelLayoutReferenceGuide: Int {
     case superview = 0
     case safeArea = 1
 }
 
 extension FloatingPanelLayoutReferenceGuide {
-    func layoutGuide(vc: UIViewController) -> LayoutGuideProvider {
+    func layoutGuide(vc: UIViewController) -> any LayoutGuideProvider {
         switch self {
         case .safeArea:
             return vc.view.safeAreaLayoutGuide
@@ -45,6 +47,7 @@ extension FloatingPanelLayoutReferenceGuide {
 }
 
 /// A representation to specify a bounding box which limit the content size of a panel.
+@MainActor
 @objc public enum FloatingPanelLayoutContentBoundingGuide: Int {
     case none = 0
     case superview = 1
@@ -52,7 +55,7 @@ extension FloatingPanelLayoutReferenceGuide {
 }
 
 extension FloatingPanelLayoutContentBoundingGuide {
-    func layoutGuide(_ fpc: FloatingPanelController) -> LayoutGuideProvider? {
+    func layoutGuide(_ fpc: FloatingPanelController) -> (any LayoutGuideProvider)? {
         switch self {
         case .superview:
             return fpc.view

Sources/Logging.swift

@@ -3,11 +3,11 @@
 import os.log
 
 let msg = StaticString("%{public}@")
-let sysLog = OSLog(subsystem: Logging.subsystem, category: Logging.category)
+nonisolated(unsafe) let sysLog = OSLog(subsystem: Logging.subsystem, category: Logging.category)
 #if FP_LOG
 let devLog = OSLog(subsystem: Logging.subsystem, category: "\(Logging.category):dev")
 #else
-let devLog = OSLog.disabled
+nonisolated(unsafe) let devLog = OSLog.disabled
 #endif
 
 struct Logging {
@@ -15,14 +15,3 @@ struct Logging {
     static let category = "FloatingPanel"
     private init() {}
 }
-
-extension String.StringInterpolation {
-    mutating func appendInterpolation<T>(optional: T?, defaultValue: String = "nil") {
-        switch optional {
-        case let value?:
-            appendLiteral(String(describing: value))
-        case nil:
-            appendLiteral(defaultValue)
-        }
-    }
-}

Sources/Position.swift

@@ -3,6 +3,7 @@
 import UIKit
 
 /// Constants describing the position of a panel in a screen
+@MainActor
 @objc public enum FloatingPanelPosition: Int {
     case top
     case left
@@ -25,7 +26,7 @@ extension FloatingPanelPosition {
         }
     }
 
-    func mainDimensionAnchor(_ layoutGuide: LayoutGuideProvider) -> NSLayoutDimension {
+    func mainDimensionAnchor(_ layoutGuide: any LayoutGuideProvider) -> NSLayoutDimension {
         switch self {
         case .top, .bottom: return layoutGuide.heightAnchor
         case .left, .right: return layoutGuide.widthAnchor

Sources/State.swift

@@ -4,7 +4,7 @@ import Foundation
 
 /// An object that represents the display state of a panel in a screen.
 @objc
-open class FloatingPanelState: NSObject, NSCopying, RawRepresentable {
+public final class FloatingPanelState: NSObject, NSCopying, RawRepresentable, Sendable {
     public typealias RawValue = String
 
     required public init?(rawValue: RawValue) {

Sources/Transitioning.swift

@@ -5,11 +5,11 @@ import UIKit
 class ModalTransition: NSObject, UIViewControllerTransitioningDelegate {
     func animationController(forPresented presented: UIViewController,
                              presenting: UIViewController,
-                             source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
+                             source: UIViewController) -> (any UIViewControllerAnimatedTransitioning)? {
         return ModalPresentTransition()
     }
 
-    func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
+    func animationController(forDismissed dismissed: UIViewController) -> (any UIViewControllerAnimatedTransitioning)? {
         return ModalDismissTransition()
     }
 
@@ -81,16 +81,16 @@ class PresentationController: UIPresentationController {
 }
 
 class ModalPresentTransition: NSObject, UIViewControllerAnimatedTransitioning {
-    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
+    func transitionDuration(using transitionContext: (any UIViewControllerContextTransitioning)?) -> TimeInterval {
         guard
             let fpc = transitionContext?.viewController(forKey: .to) as? FloatingPanelController
-        else { return 0.0 }
+        else { fatalError()}
 
         let animator = fpc.animatorForPresenting(to: fpc.layout.initialState)
         return TimeInterval(animator.duration)
     }
 
-    func interruptibleAnimator(using transitionContext: UIViewControllerContextTransitioning) -> UIViewImplicitlyAnimating {
+    func interruptibleAnimator(using transitionContext: any UIViewControllerContextTransitioning) -> any UIViewImplicitlyAnimating {
         guard
             let fpc = transitionContext.viewController(forKey: .to) as? FloatingPanelController
         else { fatalError() }
@@ -110,22 +110,22 @@ class ModalPresentTransition: NSObject, UIViewControllerAnimatedTransitioning {
         return transitionAnimator
     }
 
-    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+    func animateTransition(using transitionContext: any UIViewControllerContextTransitioning) {
         self.interruptibleAnimator(using: transitionContext).startAnimation()
     }
 }
 
 class ModalDismissTransition: NSObject, UIViewControllerAnimatedTransitioning {
-    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
+    func transitionDuration(using transitionContext: (any UIViewControllerContextTransitioning)?) -> TimeInterval {
         guard
             let fpc = transitionContext?.viewController(forKey: .from) as? FloatingPanelController
-        else { return 0.0 }
+        else { fatalError()}
 
         let animator = fpc.animatorForDismissing(with: .zero)
         return TimeInterval(animator.duration)
     }
 
-    func interruptibleAnimator(using transitionContext: UIViewControllerContextTransitioning) -> UIViewImplicitlyAnimating {
+    func interruptibleAnimator(using transitionContext: any UIViewControllerContextTransitioning) -> any UIViewImplicitlyAnimating {
         guard
             let fpc = transitionContext.viewController(forKey: .from) as? FloatingPanelController
         else { fatalError() }
@@ -142,7 +142,7 @@ class ModalDismissTransition: NSObject, UIViewControllerAnimatedTransitioning {
         return fpc.transitionAnimator!
     }
 
-    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+    func animateTransition(using transitionContext: any UIViewControllerContextTransitioning) {
         self.interruptibleAnimator(using: transitionContext).startAnimation()
     }
 }

Tests/CoreTests.swift

@@ -916,34 +916,6 @@ class CoreTests: XCTestCase {
         }
     }
 
-    func test_initial_scroll_offset_reset() {
-        let fpc = FloatingPanelController()
-        let scrollView = UIScrollView()
-        fpc.layout = FloatingPanelBottomLayout()
-        fpc.track(scrollView: scrollView)
-        fpc.showForTest()
-
-        fpc.move(to: .full, animated: false)
-
-        fpc.panGestureRecognizer.state = .began
-        fpc.floatingPanel.handle(panGesture: fpc.panGestureRecognizer)
-
-        fpc.panGestureRecognizer.state = .cancelled
-        fpc.floatingPanel.handle(panGesture: fpc.panGestureRecognizer)
-
-        waitRunLoop(secs: 1.0)
-
-        let expect = CGPoint(x: 0, y: 100)
-
-        scrollView.setContentOffset(expect, animated: false)
-
-        fpc.move(to: .half, animated: true)
-
-        waitRunLoop(secs: 1.0)
-
-        XCTAssertEqual(expect, scrollView.contentOffset)
-    }
-
     func test_handleGesture_endWithoutAttraction() throws {
         class Delegate: FloatingPanelControllerDelegate {
             var willAttract: Bool?