With the introduction of the new matchedTransitionSource from iOS 18, we can apply a zoom transition in the navigation view using .navigationTransition(.zoom) This works well for zoom animations. However, when I try to apply a matched geometry effect to views that are similar in the source and destination views, the zoom transition works, but those views don't transition seamlessly as they do with a matched geometry effect. Is it possible to still use matched geometry for subviews of the source and destination views along with the new navigationTransition? Here’s a little demo that reproduces this behaviour: struct ContentView: View { let colors: [[Color]] = [ [.red, .blue, .green], [.yellow, .purple, .brown], [.cyan, .gray] ] @Namespace() var namespace var body: some View { NavigationStack { Grid(horizontalSpacing: 50, verticalSpacing: 50) { ForEach(colors, id: \.hashValue) { rowColors in GridRow { ForEach(rowColors, id: \.self) { color in NavigationLink { DetailView(color: color, namespace: namespace) .navigationTransition( .zoom( sourceID: color, in: namespace ) ) .edgesIgnoringSafeArea(.all) } label: { ZStack { RoundedRectangle(cornerRadius: 5) .foregroundStyle(color) .frame(width: 48, height: 48) Image(systemName: "star.fill") .foregroundStyle(Material.bar) .matchedGeometryEffect(id: color, in: namespace, properties: .frame, isSource: false) } } .matchedTransitionSource(id: color, in: namespace) } } } } } } } struct DetailView: View { var color: Color let namespace: Namespace.ID var body: some View { ZStack { color Image(systemName: "star.fill") .resizable() .foregroundStyle(Material.bar) .matchedGeometryEffect(id: color, in: namespace, properties: .frame, isSource: false) .frame(width: 100, height: 100) } .navigationBarHidden(false) } } #Preview { ContentView() }

I want to show a view, where the user can add or remove items shown as icons, which are sorted in two groups: squares and circles. When there are only squares, they should be shown in one row: [] [] [] When there are so many squares that they don’t fit horizontally, a (horizontal) scrollview will be used, with scroll-indicator always shown to indicate that not all squares are visible. When there are only circles, they also should be shown in one row: () () () When there are so many circles that they don’t fit horizontally, a (horizontal) scrollview will be used, with scroll-indicator always shown to indicate that not all circles are visible. When there a few squares and a few circles, they should be shown adjacent in one row: [] [] () () When there are so many squares and circles that they don’t fit horizontally, they should be shown in two rows, squares on top, circles below: [] [] [] () () () When there are either too many squares or too many circles (or both) to fit horizontally, one common (horizontal) scrollview will be used, with scroll-indicator always shown to indicate that not all items are visible. I started with ViewThatFits: (see first code block) { let squares = HStack { ForEach(model.squares, id: \.self) { square in Image(square) } } let circles = HStack { ForEach(model.circles, id: \.self) { circle in Image(circle) } } let oneLine = HStack { squares circles } let twoLines = VStack { squares circles } let scrollView = ScrollView(.horizontal) { twoLines }.scrollIndicators(.visible) ViewThatFits(in: .horizontal) { oneLine twoLines scrollView.clipped() } } While this works in general, it doesn’t animate properly. When the user adds or removes an image the model gets updated, (see second code block) withAnimation(Animation.easeIn(duration: 0.25)) { model.squares += image } and the view animates with the existing images either making space for a new appearing square/circle, or moving together to close the gap where an image disappeared. This works fine as long as ViewThatFits returns the same view. However, when adding 1 image leads to ViewThatFits switching from oneLine to twoLines, this switch is not animated. The circles jump to the new position under the squares, instead of sliding there. I searched online for a solution, but this seems to be a known problem of ViewThatFits. It doesn't animate when it switches... (tbc)

Hi, when I run NavigationSplitView as shown below, the sidebar opens and closes smoothly. struct TestingView: View { var body: some View { NavigationSplitView { Text("Sidebar") } detail: { Text("Detail") } } } However, when I add a minimum width, the sidebar animation starts to lag. I tried various wapping solutions, but I couldn’t get rid of the stutter. struct TestingView: View { var body: some View { NavigationSplitView { Text("Sidebar") } detail: { Text("Detail") } .frame(minWidth: 800) } } As a solution, I had to disable the animation completely: .animation(nil, value: columnVisibility) Is there a way to keep the animation without the stuttering?

Is there some reason UIKit's and AppKit's animate(with:changes:completion:) methods are marked deprecated in iOS 18 when they were also first made available in iOS18? If they are indeed already deprecated, is there a replacement method we are supposed to use? This method allows the developer to use SwiftUI animations to animate UIKit and AppKit views.

SwiftUI Navigation Stack Zoom Transition – Title Animation Issue (iOS 18) In the WWDC24 video "Enhance your UI animations and transitions", Apple demonstrates how the navigation stack title smoothly animates into the back button in the new view when using a zoom transition: NavigationLink { BraceletEditor(bracelet) .navigationTransitionStyle( .zoom( sourceID: bracelet.id, in: braceletList ) ) } label: { BraceletPreview(bracelet) } .matchedTransitionSource( id: bracelet.id, in: braceletList ) However, I cannot get this animation. Expected (from WWDC video): Actual (iOS 18 simulator): How can I get the original animation?

Hello! I’m experiencing a crash in my iOS/iPadOS app related to a CALayer rendering process. The crash occurs when attempting to render a UIImage on a background thread. The crashes are occurring in our production app, and while we can monitor them through Crashlytics, we are unable to reproduce the issue in our development environment. Relevant Code I have a custom view controller that handles rendering CALayers onto images. This method creates a CALayer on the main thread and then starts a detached task to render this CALayer into a UIImage. The whole idea is learnt from this StackOverflow post: https://stackoverflow.com/a/77834613/9202699 Here are key parts of my implementation: class MyViewController: UIViewController { @MainActor func renderToUIImage(size: CGSize, itemsToDraw: [MyDrawingItem], transform: CGAffineTransform) async -> UIImage? { // Create CALayer and add it to the view. CATransaction.begin() let customLayer = MyDrawingLayer() customLayer.setupContent(itemsToDraw: itemsToDraw) // Position the frame off-screen to it hidden. customLayer.frame = CGRect( origin: CGPoint(x: -100 - size.width, y: -100 - size.height), size: size) customLayer.masksToBounds = true customLayer.drawsAsynchronously = true view.layer.addSublayer(customLayer) CATransaction.commit() // Render CALayer to UIImage in background thread. let image = await Task.detached { customLayer.setNeedsDisplay() let renderer = UIGraphicsImageRenderer(size: size) let image = renderer.image { // CRASH happens on this line let cgContext = $0.cgContext cgContext.saveGState() cgContext.concatenate(transform) customLayer.render(in: cgContext) cgContext.restoreGState() } return image }.value // Remove the CALayer from the view. CATransaction.begin() customLayer.removeFromSuperlayer() CATransaction.commit() return image } } class MyDrawingLayer: CALayer { var itemsToDraw: [MyDrawingItem] = [] func setupContent(itemsToDraw: [MyDrawingItem]) { self.itemsToDraw = itemsToDraw } override func draw(in ctx: CGContext) { for item in itemsToDraw { // Render the item to the context (example pseudo-code). // All items are thread-safe to use. // Things to draw may include CGPath, CGImages, UIImages, NSAttributedString, etc. item.draw(in: ctx) } } } Crash Log The crash occurs at the following location: Crashed: com.apple.root.default-qos.cooperative 0 MyApp 0x5cb300 closure #1 in closure #1 in MyViewController.renderToUIImage(size: CGSize, itemsToDraw: [MyDrawingItem], transform: CGAffineTransform) + 4313002752 (<compiler-generated>:4313002752) 1 MyApp 0x5cb300 closure #1 in closure #1 in MyViewController.renderToUIImage(size: CGSize, itemsToDraw: [MyDrawingItem], transform: CGAffineTransform) + 4313002752 (<compiler-generated>:4313002752) 2 MyApp 0x1a4578 AnyModifier.modified(for:) + 4308649336 (<compiler-generated>:4308649336) 3 MyApp 0x7b4e64 thunk for @escaping @callee_guaranteed (@guaranteed UIGraphicsPDFRendererContext) -> () + 4315008612 (<compiler-generated>:4315008612) 4 UIKitCore 0x1489c0 -[UIGraphicsRenderer runDrawingActions:completionActions:format:error:] + 324 5 UIKitCore 0x14884c -[UIGraphicsRenderer runDrawingActions:completionActions:error:] + 92 6 UIKitCore 0x148778 -[UIGraphicsImageRenderer imageWithActions:] + 184 7 MyApp 0x5cb1c0 closure #1 in MyViewController.renderToUIImage(size: CGSize, itemsToDraw: [MyDrawingItem], transform: CGAffineTransform) + 100 (FileName.swift:100) 8 libswift_Concurrency.dylib 0x60f5c swift::runJobInEstablishedExecutorContext(swift::Job*) + 252 9 libswift_Concurrency.dylib 0x62514 swift_job_runImpl(swift::Job*, swift::SerialExecutorRef) + 144 10 libdispatch.dylib 0x15ec0 _dispatch_root_queue_drain + 392 11 libdispatch.dylib 0x166c4 _dispatch_worker_thread2 + 156 12 libsystem_pthread.dylib 0x3644 _pthread_wqthread + 228 13 libsystem_pthread.dylib 0x1474 start_wqthread + 8 Questions Is it safe to run UIGraphicsImageRenderer.image on the background thread? Given that I want to leverage GPU rendering, what are some best practices for rendering images off the main thread while ensuring stability? Are there alternatives to using UIGraphicsImageRenderer for background rendering that can still take advantage of GPU rendering? It is particularly interesting that the crash logs indicate the error may be related to UIGraphicsPDFRendererContext (crash log line number 3). It would be very helpful if someone could explain the connection between starting and drawing on a UIGraphicsImageRenderer and UIGraphicsPDFRendererContext. Any insights or guidance on this issue would be greatly appreciated. Thanks!!!

In Apple's Maps app, an annotation is made up of a circle shape or rounded rectangles with a glyph-image. When selecting an annotation, the annotation animates into a balloon marker (see attached GIF). How does Apple Maps solve this - from custom annotation to balloon marker with spring animation? I switched my Maps implementation from SwiftUI to UIKit with a UIViewRepresentable to support annotation clustering - and it works beautifully. But how to subclass an MKAnnotationView (or MKMarkerAnnotationView <- the balloon) to enable selection and animation as in Apple Maps? MKMarkerAnnotationView only show balloon markers and I tried everything inside MKAnnotationView (CALayer, etc.)

I have a bare-bones Metal app setup where I attach a CAMetalLayer to a window that inherits from a NSWindow with a custom delegate. Everything else is vanilla. I'm also using metal-cpp and metal shader converter. I'm running into a issue where the application runs fine in the beginning, but once I resize the window, it starts hitching. It turns out that [CAMetalLayer nextDrawable:] frequently (but not always) takes around a full second (plus or minus a few milliseconds) to return once drawableSize has been updated. I've tried setting allowsNextDrawableTimeout to false which doesn't work; it returns a valid drawable after a second instead of nil. Setting displaySyncEnabled to false reduces the likelihood of this happening to around 50% from 90%+ but does not eliminate it. Setting maximumDrawableCount to 2 or 3 does not seem to make a difference. By dumping the resource IDs of the returned textures I've noticed something interesting: Before resizing, the layer seems to shuffle between 2 textures or at least 2 resource IDs, but after resizing it starts to create new textures for each returned drawable. Occasionally it seems to reuse a previous resource ID, but it does not seem to have anything to do with whether the method returns quickly or not. Why does this happen, and how can I fix it? Should I create a new CAMetalLayer when resizing the window instead of updating drawableSize?

Problem Description We are developing a app for iOS and iPadOS that involves extensive custom drawing of paths, shapes, texts, etc. To improve drawing and rendering speed, we use CARenderer to generate cached images (CGImage) on a background thread. We adopted this approach based on this StackOverflow post: https://stackoverflow.com/a/75497329/9202699. However, we are experiencing frequent crashes in our production environment that we can hardly reproduce in our development environment. Despite months of debugging and seeking support from DTS and the Apple Feedback platform, we have not been able to fully resolve this issue. Our recent crash reports indicate that the crashes occur when calling CATransaction.commit(). We suspect that CATransaction may not be functioning properly outside the main thread. However, based on feedback from the Apple Feedback platform, we were advised to use CATransaction.begin() and CATransaction.commit() on a background thread. If anyone has any insights, we would greatly appreciate it. Code Sample The line CATransaction.commit() is causing the crash: [EXC_BREAKPOINT: com.apple.root.****-qos.cooperative] private let transactionLock = NSLock() // to ensure one transaction at a time private let device = MTLCreateSystemDefaultDevice()! @inline(never) static func drawOnCGImageWithCARenderer( layerRect: CGRect, itemsToDraw: [ItemsToDraw] ) -> CGImage? { // We have encapsulated everything related to CALayer and its // associated creations and manipulations within CATransaction // as suggested by engineers from Apple Feedback Portal. transactionLock.lock() CATransaction.begin() // Create the root layer. let layer = CALayer() layer.bounds = layerRect layer.masksToBounds = true // Add one sublayer for each item to draw itemsToDraw.forEach { item in // We have thousands or hundred thousands of drawing items to add. // Each drawing item may produce a CALayer, CAShapeLayer or CATextLayer. // This is also why we want to utilise CARenderer to leverage GPU rendering. layer.addSublayer( item.createCALayerOrCATextLayerOrCAShapeLayer() ) } // Create MTLTexture and CARenderer. let textureDescriptor = MTLTextureDescriptor.texture2DDescriptor( pixelFormat: .rgba8Unorm, width: Int(layer.frame.size.width), height: Int(layer.frame.size.height), mipmapped: false ) textureDescriptor.usage = [MTLTextureUsage.shaderRead, .shaderWrite, .renderTarget] let texture = device.makeTexture(descriptor: textureDescriptor)! let renderer = CARenderer(mtlTexture: texture) renderer.bounds = layer.frame renderer.layer = layer.self /* ********************************************************* */ // From our crash report, this is where the crash happens. CATransaction.commit() /* ********************************************************* */ transactionLock.unlock() // Rendering layers onto MTLTexture using CARenderer. renderer.beginFrame(atTime: 0, timeStamp: nil) renderer.render() renderer.endFrame() // Draw MTLTexture onto image. guard let colorSpace = CGColorSpace(name: CGColorSpace.sRGB), let ciImage = CIImage(mtlTexture: texture, options: [.colorSpace: colorSpace]) else { return nil } // Convert CIImage to CGImage. let context = CIContext() return context.createCGImage(ciImage, from: ciImage.extent) }

Description We are developing a app for iOS and iPadOS that involves extensive custom drawing of paths, shapes, texts, etc. To improve drawing and rendering speed, we use CARenderer to generate cached images (CGImage) on a background thread. We adopted this approach based on this StackOverflow post: https://stackoverflow.com/a/75497329/9202699. However, we are experiencing frequent crashes in our production environment that we cannot reproduce in our development environment. Despite months of debugging and seeking support from DTS and the Apple Feedback platform, we have not been able to fully resolve this issue. Our recent crash reports indicate that the crashes occur when calling CATransaction.commit(). Crash traceback The method names in this traceback are mapped to those in the code sample below. The app name has been masked. Crashed: com.apple.root.user-initiated-qos.cooperative 0 MyApp 0x887408 specialized static CAUtils.commitCATransaction() + 4340151304 (<compiler-generated>:4340151304) 1 MyApp 0x887408 specialized static CAUtils.commitCATransaction() + 4340151304 (<compiler-generated>:4340151304) 2 MyApp 0x8874a4 specialized static CAUtils.addDrawingItemsToRenderer(xxx) + 250 (CAUtils.swift:250) 3 MyApp 0x887710 specialized static CAUtils.drawOnCGImageWithCARenderer(xxx) + 267 (CAUtils.swift:267) 4 MyApp 0x8878c0 specialized static CAUtils.drawOnCGImageWithCARendererWithRetry(xxx) + 315 (CAUtils.swift:315) 5 MyApp 0x736294 XXXManager.generateCGImages(xxx) + 570 (XXXManager.swift:570) 6 MyApp 0x73404c closure #1 in XXXManager.updateCachedCGImages(xxx) + 427 (XXXManager.swift:427) 7 libswift_Concurrency.dylib 0x61104 swift::runJobInEstablishedExecutorContext(swift::Job*) + 252 8 libswift_Concurrency.dylib 0x62514 swift_job_runImpl(swift::Job*, swift::SerialExecutorRef) + 144 9 libdispatch.dylib 0x15d8c _dispatch_root_queue_drain + 392 10 libdispatch.dylib 0x16590 _dispatch_worker_thread2 + 156 11 libsystem_pthread.dylib 0x4c40 _pthread_wqthread + 228 12 libsystem_pthread.dylib 0x1488 start_wqthread + 8 Code Sample Below is a sample of our code. While the complete snippet is too long, the issue occurs in addDrawingItemsToRenderer. Please refer to the other methods for completeness and reference purposes. private let transactionLock = NSLock() private let deviceLock = NSLock() private let device = MTLCreateSystemDefaultDevice()! /// This is the method we call from outside. @inline(never) static func drawOnCGImageWithCARenderer( layerRect: CGRect, drawingItems: [DrawingItem] ) -> CGImage? { guard let (texture, renderer) = addDrawingItemsToRenderer( layerRect: layerRect, drawingItems: drawingItems ) else { return nil } renderer.beginFrame(atTime: 0, timeStamp: nil) renderer.render() renderer.endFrame() guard let colorSpace = CGColorSpace(name: CGColorSpace.sRGB), let ciImage = CIImage(mtlTexture: texture, options: [.colorSpace: colorSpace]) else { return nil } let context = CIContext() return context.createCGImage(ciImage, from: ciImage.extent) } /// This is the method will the crash happens @inline(never) fileprivate static func addDrawingItemsToRenderer( layerRect: CGRect, drawingItems: [DrawingItem] ) -> (MTLTexture, CARenderer)? { // We have encapsulated everything related to CALayer and its // associated creations and manipulations within CATransaction // as suggested by engineers from Apple Feedback Portal. beginCATransaction() defer { commitCATransaction() // The crash happens here } let (layer, imageWidth, imageHeight) = addDrawingItemsToLayer(layerRect: layerRect, drawingItems: drawingItems) return createTextureAndRenderer( layer: layer, imageWidth: imageWidth, imageHeight: imageHeight ) } // Below are all internal methods. We have split the method into very // granular parts and marked them as @inline(never) to prevent the // compiler from inlining our code, which may otherwise obscure usage // trackback information in our crash reports. @inline(never) fileprivate static func beginCATransaction() { transactionLock.lock() CATransaction.begin() } @inline(never) fileprivate static func commitCATransaction() { // From our crash report, we believe the crash happens on this line. CATransaction.commit() // It is unlikely that the lock cause the crash as we added it only recently // to ensure that there is only one transaction on our background thread, // and after we added this lock, the crash rate indeed lowered, but still // not fully disappear transactionLock.unlock() } -------------------------------- // The methods below are provided for reference and completeness. While // they may have issues, they do not frequently appear in our crash // reports as the one caused by `CATransaction.commit()` @inline(never) fileprivate static func addDrawingItemsToLayer( layerRect: CGRect, drawingItems: [DrawingItem] ) -> (layer: CALayer, imageWidth: CGFloat, imageHeight: CGFloat) { let layer = CALayer() layer.isGeometryFlipped = SharedAppUtils.isIOS layer.anchorPoint = CGPoint.zero layer.bounds = layerRect layer.masksToBounds = true for drawingItem in drawingItems { // We have thousands or hundred thousands of drawing items to add. // Each drawing item may produce a CALayer, CAShapeLayer or CATextLayer. // This is also why we want to utilise CARenderer to leverage GPU rendering. let sublayerForDrawingItem = drawingItem.createCALayerOrCATextLayerOrCAShapeLayer() layer.addSublayer(sublayerForDrawingItem) } let imageWidth = max(1, layer.frame.size.width * UIScreen.main.scale) let imageHeight = max(1, layer.frame.size.height * UIScreen.main.scale) layer.transform = CATransform3DMakeScale(UIScreen.main.scale, UIScreen.main.scale, 1) layer.frame = .init(origin: .zero, size: .init(width: imageWidth, height: imageHeight)) return (layer, imageWidth, imageHeight) } @inline(never) fileprivate static func createTextureAndRenderer( layer: CALayer, imageWidth: CGFloat, imageHeight: CGFloat ) -> (MTLTexture, CARenderer)? { deviceLock.lock() defer { deviceLock.unlock() } let textureDescriptor = MTLTextureDescriptor.texture2DDescriptor( pixelFormat: .rgba8Unorm, width: Int(imageWidth), height: Int(imageHeight), mipmapped: false ) textureDescriptor.usage = [MTLTextureUsage.shaderRead, .shaderWrite, .renderTarget] guard let texture = device.makeTexture(descriptor: textureDescriptor) else { return nil } let renderer = CARenderer(mtlTexture: texture) renderer.bounds = layer.frame renderer.layer = layer.self return (texture, renderer) }

Safari throw a ViewTransition error, called ' Unhandled Promise Rejection: AbortError: Old view transition aborted by new view transition.' however, i don't find how to catch it. i used 'try..catch' or Promise.catch, or catch it in finished/ready/updateCallbackDone Promise. These all don't work.

Hi everyone, im in the process of delving more into coregraphics with swiftui, but I am at a roadblock. First I would like to ask, what are some good resources to learn coregraphics? Secondly: I currently have a circle view made and what I want to do is to make my circle view modular so that it can be directly connected to another given circle by a line. How can I do this? For example, I want my circles to represent nodes and be able to connect by lines to other nodes that are related. Thanks in advanced. Here is my code for the circle view: @State private var circleProgress: CGFloat = 0 let timer = Timer.publish(every: 0.016, on: .main, in: .common).autoconnect() private let animationDuration: TimeInterval = 1.5 @Binding var startPoint: CGPoint @Binding var endPoint: CGPoint var body: some View { GeometryReader { geometry in Canvas { context, size in // Circle parameters let circleSize: CGFloat = 50 let circleOrigin = CGPoint( x: size.width / 4, y: size.height / 2 - circleSize / 2 ) let circleRect = CGRect( origin: circleOrigin, size: CGSize(width: circleSize, height: circleSize) ) let circleCenter = CGPoint( x: circleOrigin.x + circleSize / 2, y: circleOrigin.y + circleSize / 2 ) // Animate circle creation var circlePath = Path() circlePath.addArc( center: circleCenter, radius: circleSize / 2, startAngle: .degrees(0), endAngle: .degrees(360 * circleProgress), clockwise: false ) context.addFilter(.shadow(color: .white.opacity(0.6), radius: 5, x: 1, y: 1)) // Add white shadow context.stroke( circlePath, with: .linearGradient( Gradient(colors: [.purple, .white]), startPoint: circleRect.origin, endPoint: CGPoint(x: circleRect.maxX, y: circleRect.maxY) ), lineWidth: 5 ) } .frame(width: 300, height: 150) .onReceive(timer) { _ in // Update circle progress let progressChange = 0.02 / animationDuration if circleProgress < 1.0 { circleProgress = min(circleProgress + progressChange, 1.0) } else { circleProgress = 0.0 // Reset the circle to repeat the animation } // Get the starting and ending points of the Canvas view startPoint = CGPoint(x: geometry.frame(in: .global).minX, y: geometry.frame(in: .global).minY) endPoint = CGPoint(x: geometry.frame(in: .global).maxX, y: geometry.frame(in: .global).maxY) // Print the points for debugging print("Start Point: \(startPoint.x), \(startPoint.y)") print("End Point: \(endPoint.x), \(endPoint.y)") } } .frame(width: 300, height: 150) } }

I plan to create a simple motion graphics software for macOS that animates text, basic shapes, and handles audio. I'll use SwiftUI for the UI. What are the commonly used technologies for rendering animated graphics? Core Animation is suitable for UI animations but not for exporting and controlling UI animations. Basic requirements: Timeline user interface Animation of text and basic shapes Viewer in SwiftUI GUI with transport control (play, pause, scrub, …) Export to video file Is Metal or Core Graphics typically used directly? I want to keep it as simple as possible.

I have a CALayer and I'd like to animate a property on it. But, the property that triggers the animation change is different to the one that is being changed. A basic example of what I'm trying to do is below. I'm trying to create an animation on count by changing triggerProperty. This example is simplified (in my project, the triggerProperty is not an Int, but a more complex non-animatable type. So, I'm trying to animate it by creating animations for some of it's properties that can be matched to CABasicAnimation - and rendering a version of that class based on the interpolated values). @objc class AnimatableLayer: CALayer { @NSManaged var triggerProperty: Int @NSManaged var count: Int override init() { super.init() triggerProperty = 1 setNeedsDisplay() } override init(layer: Any) { super.init(layer: layer) } required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } override class func needsDisplay(forKey key: String) -> Bool { return key == String(keypath: \AnimatableLayer.triggerProperty) || super.needsDisplay(forKey: key) } override func action(forKey event: String) -> (any CAAction)? { if event == String(keypath: \AnimatableLayer.triggerProperty) { if let presentation = self.presentation() { let keyPath = String(keypath: \AnimatableLayer.count) let animation = CABasicAnimation(keyPath: keyPath) animation.duration = 2.0 animation.timingFunction = CAMediaTimingFunction(name: CAMediaTimingFunctionName.linear) animation.fromValue = presentation.count animation.toValue = 10 return animation } } return super.action(forKey: event) } override func draw(in ctx: CGContext) { print("draw") NSGraphicsContext.saveGraphicsState() let nsctx = NSGraphicsContext(cgContext: ctx, flipped: true) // create NSGraphicsContext NSGraphicsContext.current = nsctx // set current context let renderText = NSAttributedString(string: "\(self.presentation()?.count ?? self.count)", attributes: [.font: NSFont.systemFont(ofSize: 30)]) renderText.draw(in: bounds) NSGraphicsContext.restoreGraphicsState() } func animate() { print("animate") self.triggerProperty = 10 } } With this code, the animation isn't triggered. It seems to get triggered only if the animation's keypath matches the one on the event (in the action func). Is it possible to do something like this?

I am working on a SceneKit project where I use a CAShapeLayer as the content for SCNMaterial's diffuse.contents to display a progress bar. Here's my initial code: func setupProgressWithCAShapeLayer() { let progressLayer = createProgressLayer() progressBarPlane?.firstMaterial?.diffuse.contents = progressLayer DispatchQueue.main.async { var progress: CGFloat = 0.0 Timer.scheduledTimer(withTimeInterval: 0.1, repeats: true) { timer in progress += 0.01 if progress > 1.0 { progress = 0.0 } progressLayer.strokeEnd = progress // Update progress } } } // MARK: - ARSCNViewDelegate func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) { progressBarPlane = SCNPlane(width: 0.2, height: 0.2) setupProgressWithCAShapeLayer() let planeNode = SCNNode(geometry: progressBarPlane) planeNode.position = SCNVector3(x: 0, y: 0.2, z: 0) node.addChildNode(planeNode) } This works fine, and the progress bar updates smoothly. However, when I change the code to use a class property (self.progressLayer) instead of a local variable, the rendering starts flickering on the screen: func setupProgressWithCAShapeLayer() { self.progressLayer = createProgressLayer() progressBarPlane?.firstMaterial?.diffuse.contents = progressLayer DispatchQueue.main.async { [weak self] in var progress: CGFloat = 0.0 Timer.scheduledTimer(withTimeInterval: 0.1, repeats: true) { [weak self] timer in progress += 0.01 if progress > 1.0 { progress = 0.0 } self?.progressLayer?.strokeEnd = progress // Update progress } } } After this change, the progressBarPlane in SceneKit starts flickering while being rendered on the screen. My Question: Why does switching from a local variable (progressLayer) to a class property (self.progressLayer) cause the flickering issue in SceneKit rendering?

I'm new to developing with SwiftUI and I created a Pomodoro app for macOS that runs in the menu bar. I added 4 animations and when the user selects the snow animation, it starts snowing on the screen. But the app uses 20%-30% of the CPU and has high energy consumption. I can't reduce it and I couldn't find a solution. // snow animation import SwiftUI struct SnowflakeView: View { @State private var flakeYPosition: CGFloat = -100 @State private var isAnimating = false private let flakeSize: CGFloat = CGFloat.random(in: 10...30) private let flakeColor: Color = Color( red: Double.random(in: 0.8...1), green: Double.random(in: 0.9...1), blue: Double.random(in: 1...1), opacity: Double.random(in: 0.6...0.8) ) private let animationDuration: Double = Double.random(in: 1...3) private let flakeXPosition: CGFloat = CGFloat.random(in: 0...310) var body: some View { Text("❄️") .font(.system(size: flakeSize)) .foregroundColor(flakeColor) .position(x: flakeXPosition, y: flakeYPosition) .onAppear { if !isAnimating { withAnimation(Animation.linear(duration: animationDuration).repeatForever(autoreverses: false)) { flakeYPosition = 280 + 50 } isAnimating = true } } } } I also have how I run the animation below. ZStack { ForEach(0..<10, id: \.self) { index in if selectedAnimal == "Snow" { SnowflakeView() } else if selectedAnimal == "Rain" { RainDropAnimation() }else if selectedAnimal == "Leaf"{ LeafFallAnimation() }else if selectedAnimal == "Confetti"{ ConfettiAnimation() } } }

I have facing an above crash for many users device running on iOS 17.6.1 mostly on iPad devices. I'm not sure why this happening only in 17.X. In Xcode Organizer unable to see this crash in any devices running on OS 18.x. Our app crashes got spiked due to this. I am unable to fix or reproduce the same. The crash log is not pointing to our app code to find the root cause and fix this issue. Have attached the crash log in this post also the crash log roles have mixed values Background &amp;amp; Foreground. But most of the crash is in background. Is this any crash related to system and that only solved by OS update? I have updated the app using Xcode 16 and 16.1 still facing this crash unable to symbolicate the crash report as well. Any ideas/solution how to solve this or how to proceed further. Have attached the entire crash log below. RoleBackgroundCrash.crash RoleForeGroundCrash.crash

I created a simple animation of a circle that changes sizes. The circle pulses like a heartbeat in the center of the screen. My expectation was for the CPU use to be very low, but that is not the case. In addition, even if the CPU use isn't as low as I would expect, I did not expect the CPU use to increase over time because nothing else is happening in the app. Here is the code: import SwiftUI @main struct TestApp: App { var body: some Scene { WindowGroup { SplashScreenView() } } } import SwiftUI struct SplashScreenView: View { var body: some View { ZStack { SplashNucleusView(minSize: 50, maxSize: 100) } } } import SwiftUI struct SplashNucleusView: View { let minSize: Double let maxSize: Double @State private var nucleusColor: Color = .primary @State private var nucleusRadius: Double = 10 @State private var nucleusOpacity: Double = 1.0 private var nucleusAnimation: Animation { .easeInOut(duration: 0.25) .repeatForever(autoreverses: true) } let timer = Timer.publish(every: 0.5, on: .main, in: .common).autoconnect() var body: some View { Circle() .fill(nucleusColor) .frame(width: nucleusRadius) .opacity(nucleusOpacity) .onReceive(timer) { _ in withAnimation(nucleusAnimation) { nucleusRadius = Double.random(in: minSize...maxSize) } } } } This is how the animation looks: The animation is snappy until the CPU use reaches 95%, at which point there is visible stuttering. Here is how the CPU looks when the animation duration value is 0.5 seconds and the timer publishing interval is 3 seconds: Changing the animation duration value to 0.25 seconds and the timer publishing interval to 0.5 seconds changes the CPU use as follows: The complete view has many other moving parts, which make the issue much worse. The issue is evident with only the circle view. I spent hours working with the debugger, reading about animations, and testing new approaches, but the result is always the same. Why is this happening?

I am looking to implement CAMetalDisplayLink on a separate thread on a macOS application. I am basing my implementation on the following example project: Achieving Smooth Frame Rates with Metal Display Link This project allows you to configure whether a separate thread is used for rendering by setting RENDER_ON_MAIN_THREAD in GameConfig to 0. However, when I set it to use a separate thread nothing is rendered. Stepping through the code shows that a separate thread is created, but a CAMetalDisplayLinkUpdate is never received. Does anyone know why this does not work?

I found that there is such a click-to-expand horizontally and smoothly effect in the system application called "message", which is good. I wonder if I can add a similar effect to my own app. If possible, are there any implementation ideas or examples that I can refer to? Thanks!