Proper stopping

.github/workflows/build.yml

@@ -7,6 +7,6 @@ jobs:
     steps:
     - uses: actions/checkout@v3
     - name: Build
-      run: xcodebuild build -scheme 'AnimationPlanner' -destination 'platform=iOS Simulator,name=iPhone 13'
+      run: xcodebuild build -scheme 'AnimationPlanner' -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 14 Pro'
     - name: Run tests
-      run: xcodebuild test -scheme 'AnimationPlanner' -destination 'platform=iOS Simulator,name=iPhone 13'
+      run: xcodebuild test -scheme 'AnimationPlanner' -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 14 Pro'

Sample App/AnimationPlanner-Sample.xcodeproj/project.pbxproj

@@ -17,7 +17,6 @@
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
-		3E5C6DA62848C27B00720FE8 /* CAMediaTimingFunction.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CAMediaTimingFunction.swift; sourceTree = "<group>"; };
 		3EF52D592848AEC7000F8222 /* AnimationPlanner-Sample.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = "AnimationPlanner-Sample.app"; sourceTree = BUILT_PRODUCTS_DIR; };
 		3EF52D5C2848AEC7000F8222 /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		3EF52D5E2848AEC7000F8222 /* SceneDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SceneDelegate.swift; sourceTree = "<group>"; };
@@ -72,7 +71,6 @@
 				3EF52D5C2848AEC7000F8222 /* AppDelegate.swift */,
 				3EF52D5E2848AEC7000F8222 /* SceneDelegate.swift */,
 				3EF52D602848AEC7000F8222 /* ViewController.swift */,
-				3E5C6DA62848C27B00720FE8 /* CAMediaTimingFunction.swift */,
 				3EF52D622848AEC7000F8222 /* Main.storyboard */,
 				3EF52D652848AEC8000F8222 /* Assets.xcassets */,
 				3EF52D672848AEC8000F8222 /* LaunchScreen.storyboard */,
@@ -120,7 +118,7 @@
 			attributes = {
 				BuildIndependentTargetsInParallel = 1;
 				LastSwiftUpdateCheck = 1340;
-				LastUpgradeCheck = 1340;
+				LastUpgradeCheck = 1520;
 				TargetAttributes = {
 					3EF52D582848AEC7000F8222 = {
 						CreatedOnToolsVersion = 13.4;
@@ -227,6 +225,7 @@
 				DEBUG_INFORMATION_FORMAT = dwarf;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				ENABLE_TESTABILITY = YES;
+				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu11;
 				GCC_DYNAMIC_NO_PIC = NO;
 				GCC_NO_COMMON_BLOCKS = YES;
@@ -287,6 +286,7 @@
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				ENABLE_NS_ASSERTIONS = NO;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_USER_SCRIPT_SANDBOXING = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu11;
 				GCC_NO_COMMON_BLOCKS = YES;
 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;

Sample App/AnimationPlanner-Sample/ViewController.swift

@@ -9,48 +9,64 @@ import UIKit
 import AnimationPlanner
 
 class ViewController: UIViewController {
-
+    
     lazy var subview: UIView = {
         let view = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
         view.layer.cornerCurve = .continuous
         return view
     }()
 
-    override func viewDidLoad() {
-        super.viewDidLoad()
-        view.addSubview(subview)
-    }
-
+    lazy var stopButton = newStopButton()
+    lazy var resetButton = newResetButton()
+
+    // Sequence currently performing animations
+    var runningSequence: RunningSequence?
+
+    let testStopping: Bool = true // Set to true to display buttons to stop and reset animations
+
     let performComplexAnimation: Bool = false // Set to true to run a more complex animation
-
-    override func viewDidAppear(_ animated: Bool) {
-        super.viewDidAppear(animated)
+    
+    func performAnimations() {
+        resetButton.isEnabled = false
         if performComplexAnimation {
-            runComplexBulderAnimation()
+            runComplexBuilderAnimation()
         } else {
             runSimpleBuilderAnimation()
         }
     }
+
+    override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
+        performAnimations()
+    }
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        view.addSubview(subview)
+
+        guard testStopping else {
+            return
+        }
+        view.addSubview(stopButton)
+        view.addSubview(resetButton)
+        stopButton.translatesAutoresizingMaskIntoConstraints = false
+        resetButton.translatesAutoresizingMaskIntoConstraints = false
+        NSLayoutConstraint.activate([
+            stopButton.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor),
+            stopButton.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor),
+            stopButton.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor, constant: -8),
+            resetButton.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor, constant: 8),
+            resetButton.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor),
+            resetButton.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor)
+        ])
+    }
 }
 
 extension ViewController {
 
-    func setInitialSubviewState() -> UIView {
-        subview.alpha = 0
-        subview.transform = .identity
-        subview.frame.size = CGSize(width: 100, height: 100)
-        subview.center.x = view.bounds.midX
-        subview.frame.origin.y = view.bounds.minY
-        subview.backgroundColor = .systemOrange
-        subview.layer.cornerRadius = 16
-        subview.layer.borderWidth = 0
-        subview.layer.borderColor = nil
-        return subview
-    }
-
     func runSimpleBuilderAnimation() {
         let view = setInitialSubviewState()
-        AnimationPlanner.plan {
+        runningSequence = AnimationPlanner.plan {
             Wait(0.35) // A delay waits for the given amount of seconds to start the next step
             Animate(duration: 0.32, timingFunction: .quintOut) {
                 view.alpha = 1
@@ -75,16 +91,18 @@ extension ViewController {
                 view.frame.origin.y = self.view.bounds.maxY
             }.timingFunction(.circIn)
         }.onComplete { finished in
-            // Just to keep the flow going, let‘s run the animation again
-            self.runSimpleBuilderAnimation()
+            if finished {
+                // Just to keep the flow going, let‘s run the animation again
+                self.runSimpleBuilderAnimation()
+            }
         }
     }
 
 
-    func runComplexBulderAnimation() {
+    func runComplexBuilderAnimation() {
         var sneakyCopy: UIView! // Don‘t worry, you‘ll see later
 
-        AnimationPlanner.plan {
+        runningSequence = AnimationPlanner.plan {
             let quarterHeight = view.bounds.height / 4
             let view = setInitialSubviewState()
 
@@ -112,9 +130,9 @@ extension ViewController {
 
             let loopCount = 4
 
-            // Adding mulitple steps can be done through the `Loop` struct
-            // or by adding `.animateLoop { }` to any sequence
-            Loop.through(1...loopCount) { index in
+            // Adding multiple steps can be done with a for-in statement
+            // or by adding `.mapSequence { }` or `.mapGroup { }` to any sequence
+            for index in 1...loopCount {
                 let offset = CGFloat(index) / CGFloat(loopCount)
                 let reversed = 1 - offset
                 Animate(duration: 0.32) {
@@ -183,16 +201,33 @@ extension ViewController {
                 sneakyCopy?.transform = view.transform.translatedBy(x: 0, y: quarterHeight)
             }
         }.onComplete { finished in
-            self.runComplexBulderAnimation()
+            if finished {
+                sneakyCopy.removeFromSuperview()
+                self.runComplexBuilderAnimation()
+            }
         }
     }
 }
 
 extension ViewController {
+
+    func setInitialSubviewState() -> UIView {
+        subview.alpha = 0
+        subview.transform = .identity
+        subview.frame.size = CGSize(width: 100, height: 100)
+        subview.center.x = view.bounds.midX
+        subview.frame.origin.y = view.bounds.minY
+        subview.backgroundColor = .systemOrange
+        subview.layer.cornerRadius = 16
+        subview.layer.borderWidth = 0
+        subview.layer.borderColor = nil
+        return subview
+    }
+
     /// Adds a custom shake animation sequence on the provided view
     /// - Parameter view: View to which the transform should be applied
     /// - Returns: Animations to be added to the sequence
-    @AnimationBuilder
+    @SequenceBuilder
     func addShakeSequence(shaking view: UIView) -> [SequenceAnimatable] {
         var baseTransform: CGAffineTransform = .identity
 
@@ -201,7 +236,7 @@ extension ViewController {
         let values = (0..<count).map { CGFloat($0) / CGFloat(count) }.map { $0 * maxRadius }
 
         Extra { baseTransform = view.transform }
-        Loop.through(values) { radius in
+        for radius in values {
             Animate(duration: 0.015) {
                 view.transform = baseTransform
                     .translatedBy(
@@ -213,6 +248,34 @@ extension ViewController {
     }
 }
 
+private extension ViewController {
+
+    func newStopButton() -> UIButton {
+        var configuration = UIButton.Configuration.filled()
+        configuration.buttonSize = .large
+        configuration.baseBackgroundColor = .systemRed
+        configuration.cornerStyle = .large
+        configuration.title = "Stop"
+        return UIButton(configuration: configuration, primaryAction: UIAction { [unowned self] _ in
+            runningSequence?.stopAnimations()
+            resetButton.isEnabled = true
+        })
+    }
+
+    func newResetButton() -> UIButton {
+        var configuration = UIButton.Configuration.filled()
+        configuration.buttonSize = .large
+        configuration.baseBackgroundColor = .systemGreen
+        configuration.cornerStyle = .large
+        configuration.title = "Reset"
+        let button = UIButton(configuration: configuration, primaryAction: UIAction { [unowned self] _ in
+            performAnimations()
+        })
+        button.isEnabled = false
+        return button
+    }
+}
+
 extension UIView {
     func sneakyCopy() -> Self? {
         // 🫣🫣🫣
@@ -223,7 +286,7 @@ extension UIView {
 
             let unarchiver = try NSKeyedUnarchiver(forReadingFrom: data)
             unarchiver.requiresSecureCoding = false
-
+            
             guard let view = unarchiver.decodeObject() as? Self else {
                 return nil
             }
@@ -237,4 +300,3 @@ extension UIView {
         }
     }
 }
-

Sources/AnimationPlanner/Animations/Animate.swift

@@ -9,6 +9,9 @@ public struct Animate: Animation, SequenceAnimatable, GroupAnimatable {
     public internal(set) var options: UIView.AnimationOptions?
     public internal(set) var timingFunction: CAMediaTimingFunction?
 
+    /// Class that  holds stopped state
+    internal let stopper: Stopper
+
     /// Creates a new animation, animating the properties updated in the ``changes`` closure
     ///
     /// Only the `duration` parameter is required, all other properties can be added or modified using ``AnimationModifiers``.
@@ -25,9 +28,25 @@ public struct Animate: Animation, SequenceAnimatable, GroupAnimatable {
         timingFunction: CAMediaTimingFunction? = nil,
         changes: @escaping () -> Void = {}
     ) {
+        let stopper = Stopper()
         self.duration = duration
         self.timingFunction = timingFunction
-        self.changes = changes
+        self.changes = { [weak stopper] in
+            guard stopper?.isStopped == false else {
+                return
+            }
+            stopper?.isRunning = true
+            changes()
+        }
+        self.stopper = stopper
+    }
+}
+
+extension Animate {
+    internal class Stopper {
+        var isRunning: Bool = false
+        var isStopped: Bool = false
+        var stopHandler: (() -> Void)?
     }
 }
 
@@ -56,4 +75,21 @@ extension Animate: PerformsAnimations {
             createAnimations(completion)
         }
     }
+
+    public func stop() {
+        if stopper.isRunning {
+            UIView.animate(
+                withDuration: 0,
+                delay: 0,
+                options: [
+                    .beginFromCurrentState,
+                    .overrideInheritedDuration,
+                    .overrideInheritedOptions
+                ],
+                animations: changes
+            )
+            stopper.stopHandler?()
+        }
+        stopper.isStopped = true
+    }
 }

Sources/AnimationPlanner/Animations/AnimateDelayed.swift

@@ -53,4 +53,8 @@ extension AnimateDelayed: PerformsAnimations where Contained: PerformsAnimations
     public func animate(delay leadingDelay: TimeInterval, completion: ((Bool) -> Void)?) {
         animation.animate(delay: delay + leadingDelay, completion: completion)
     }
+
+    public func stop() {
+        animation.stop()
+    }
 }

Sources/AnimationPlanner/Animations/AnimateSpring.swift

@@ -53,4 +53,8 @@ extension AnimateSpring: PerformsAnimations {
             completion: completion
         )
     }
+
+    public func stop() {
+        animation.stop()
+    }
 }

Sources/AnimationPlanner/Animations/Extra.swift

@@ -5,26 +5,33 @@ import UIKit
 public struct Extra: SequenceAnimatable, GroupAnimatable {
     public let duration: TimeInterval = 0
 
-    public var perform: () -> Void
+    /// Work item used for actually executing the closure
+    private let workItem: DispatchWorkItem
+
     public init(perform: @escaping () -> Void) {
-        self.perform = perform
+        workItem = DispatchWorkItem(block: perform)
     }
 }
 
 extension Extra: PerformsAnimations {
     public func animate(delay leadingDelay: TimeInterval, completion: ((Bool) -> Void)?) {
         let timing = timingParameters(leadingDelay: leadingDelay)
 
-        let animation: () -> Void = {
-            self.perform()
-            completion?(true)
-        }
         guard timing.delay > 0 else {
-            animation()
+            workItem.perform()
+            completion?(true)
             return
         }
-        DispatchQueue.main.asyncAfter(deadline: .now() + timing.delay) {
-            animation()
+
+        workItem.notify(queue: .main) { [weak workItem] in
+            let isFinished = workItem?.isCancelled != true
+            completion?(isFinished)
         }
+
+        DispatchQueue.main.asyncAfter(deadline: .now() + timing.delay, execute: workItem)
+    }
+
+    public func stop() {
+        workItem.cancel()
     }
 }

Sources/AnimationPlanner/Animations/Group.swift

@@ -44,4 +44,10 @@ extension Group: PerformsAnimations {
         }
         longestAnimation.animate(delay: delay, completion: completion)
     }
+
+    public func stop() {
+        for animation in animations.compactMap({ $0 as? PerformsAnimations }) {
+            animation.stop()
+        }
+    }
 }