Title: Frequent SIGSEGV crashes in QuartzCore's copy_image (iOS 18.4) We're experiencing numerous crashes with the following signature: Exception Codes: fault addr: 0x00000000000000e0 Crashed Thread: 0 Thread 0 0 QuartzCore CA::Render::copy_image(CGImage*, CGColorSpace*, unsigned int, double, double) + 1972 1 QuartzCore CA::Render::copy_image(CGImage*, CGColorSpace*, unsigned int, double, double) + 1260 2 QuartzCore CA::Render::prepare_image(CGImage*, CGColorSpace*, unsigned int, double) + 24 3 QuartzCore CA::Layer::prepare_contents(CALayer*, CA::Transaction*) + 220 4 QuartzCore CA::Layer::prepare_commit(CA::Transaction*) + 284 5 QuartzCore CA::Context::commit_transaction(CA::Transaction*, double, double*) + 488 6 QuartzCore CA::Transaction::commit() + 644 7 UIKitCore ___34-[UIApplication _firstCommitBlock]_block_invoke_2 + 36 8 CoreFoundation ___CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 28 9 CoreFoundation ___CFRunLoopDoBlocks + 352 10 CoreFoundation ___CFRunLoopRun + 868 11 CoreFoundation _CFRunLoopRunSpecific + 572 12 GraphicsServices _GSEventRunModal + 168 13 UIKitCore -[UIApplication _run] + 816 14 UIKitCore _UIApplicationMain + 336 15 kugou _main + 132 16 dyld __dyld_process_info_create + 33284 Observations: 1.Crashes consistently occur in Core Animation's image processing pipeline 2.100% of occurrences are on iOS 18.4 devices 3.Crash signature suggests memory access violation during image/copy operations 4.Not tied to any specific device model Questions for Apple: 1.Is this crash pattern recognized as a known issue in iOS 18.4? 2.Are there specific conditions that could trigger SEGV_ACCERR in CA::Render::copy_image? 3.Could this be related to color space handling or image format requirements changes? 4.Any recommended workarounds while waiting for a system update?

Title: SIGTRAP Crash in QuartzCore/CALayer during UI Lifecycle Changes Description: My app is experiencing occasional crashes triggered by a SIGTRAP signal during UI transitions (e.g., scene lifecycle changes, animations). The crash occurs in QuartzCore/UIKitCore code paths, and no business logic appears in the stack trace. Crash Context: Crash occurs sporadically during UI state changes (e.g., app backgrounding, view transitions). Stack trace involves pthread_mutex_destroy, CA::Layer::commit_if_needed, and UIKit scene lifecycle methods. Full crash log snippet: Signal: SIGTRAP Thread 0 Crashed: 0 libsystem_platform.dylib 0x... [symbol: _platform_memset$VARIANT$Haswell] 2 libsystem_pthread.dylib pthread_mutex_destroy + 64 3 QuartzCore CA::Layer::commit_if_needed(...) 4 UIKitCore UIScenePerformActionsWithLifecycleActionMask + 112 5 CoreFoundation _CFXNotificationPost + 736 Suspected Causes: Threading Issue: Potential race condition in pthread_mutex destruction (e.g., mutex used after free). UI Operation on Background Thread: CALayer/UIKit operations not confined to the main thread. Lifecycle Mismatch: Scene/UI updates after deallocation (e.g., notifications triggering late UI changes). Troubleshooting Attempted: Enabled Zombie Objects – no obvious over-released objects detected. Thread Sanitizer shows no clear data races. Verified UIKit/CoreAnimation operations are dispatched to MainThread. Request for Guidance: Are there known issues with CA::Layer::commit_if_needed and scene lifecycle synchronization? How to debug SIGTRAP in system frameworks when no app code is in the stack? Recommended tools/approaches to isolate the mutex destruction issue.

Hi Apple team and community, We’re encountering a strange issue with Live Activity that seems related to memory management or background lifecycle. ❓ Issue: Our app updates a Live Activity regularly (every 3 minutes) using .update(...). However, after the app remains in the background for around 8 hours, the Live Activity reverts to the initial state that was passed into .request(...). Even though the app continues sending updates in the background, the UI on the Lock Screen and Dynamic Island resets to the original state.

Here is a relatively simple code fragment: let attributedQuote: [NSAttributedString.Key: Any] = [ .font: FieldFont!, .foregroundColor: NSColor.red] let strQuote = NSAttributedString.init(string:"Hello World", attributes:attributedQuote) strQuote.draw(in: Rect1) It compiles without an issue, bur when I execute it, I get: "*** -colorSpaceName not valid for the NSColor <NSColor: 0x6000005adfd0>; need to first convert colorspace." I have tried everything I can think of. What's going on?

There's an easily reproducible SwiftUI bug on macOS where an app's UI state no longer updates/re-renders for "Designed for iPad" apps (i.e. ProcessInfo.processInfo.isiOSAppOnMac == true). The bug occurs in Xcode and also if the app is running independent of Xcode. The bug occurs when: the user Hides the app (i.e. it goes into the background) the user puts the Mac to sleep (e.g. Apple menu > Sleep) a total of ~60 seconds transpires (i.e. macOS puts the app into the "suspended state") when the app is brought back into the foreground the UI no longer updates properly The only way I have found to fix this is to manually open a new actual full app window via File > New, in which case the app works fine again in the new window. The following extremely simple code in a default Xcode project illustrates the issue: import SwiftUI @main struct staleApp: App { @State private var isBright = true var body: some Scene { WindowGroup() { ZStack { (isBright ? Color.white : Color.black).ignoresSafeArea() Button("TOGGLE") { isBright.toggle(); print("TAPPED") } } .onAppear { print("\(isBright ? "light" : "dark") view appeared") } } } } For the code above, after Hiding the app and putting the computer to sleep for 60 seconds or more, the button no longer swaps views, although the print statements still appear in the console upon tapping the button. Also, while in this buggy state, i can get the view to update to the current state (i.e. the view triggered by the last tap) by manually dragging the corner of the app window to resize the window. But after resizing, the view again does not update upon button tapping until I resize the window again. so it appears the diff engine is mucked or that the Scene or WindowGroup are no longer correctly running on the main thread I have tried rebuilding the entire view hierarchy by updating .id() on views but this approach does NOT work. I have tried many other options/hacks but have not been able to reset the 'view engine' other than opening a new window manually or by using: @Environment(.openWindow) private var openWindow openWindow could be a viable solution except there's no way to programmatically close the old window for isiOSAppOnMac (@Environment(.dismissWindow) private var dismissWindow doesn't work for iOS)

My code extension MyViewController: UICollectionViewDelegate, UICollectionViewDataSource { func collectionView( _ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath ) -> UICollectionViewCell { if let cell = collectionView.dequeueReusableCell( withReuseIdentifier: "CollectionViewCellID", for: indexPath ) as? CollectionViewCell { cell.setup() return cell } return UICollectionViewCell() } func collectionView( _ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath ) { // Unnecessary dequeue guard collectionView.dequeueReusableCell( withReuseIdentifier: "CollectionViewCellID", for: indexPath ) is CollectionViewCell else { return } // My action for selecting cell print("Cell Selected") } } Error: *** Assertion failure in -[UICollectionView _updateVisibleCellsNow:], UICollectionView.m:5673 *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Expected dequeued view to be returned to the collection view in preparation for display. When the collection view's data source is asked to provide a view for a given index path, ensure that a single view is dequeued and returned to the collection view. Avoid dequeuing views without a request from the collection view. For retrieving an existing view in the collection view, use -[UICollectionView cellForItemAtIndexPath:] or -[UICollectionView supplementaryViewForElementKind:atIndexPath:]. Solution: The problem was doing unnecessary dequeuing in didSelectItemAt when selecting the cell. In previous iOS like 17 or 16 or lower, it was allowed to dequeue where it is not really needed but from iOS 18, it may restricted to unnecessary dequeuing. So better to remove dequeue and use cellForItem(at) if we need to get cell from collection view. Example extension MyViewController: UICollectionViewDelegate, UICollectionViewDataSource { func collectionView( _ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath ) -> UICollectionViewCell { if let cell = collectionView.dequeueReusableCell( withReuseIdentifier: "CollectionViewCellID", for: indexPath ) as? CollectionViewCell { cell.setup() return cell } return UICollectionViewCell() } func collectionView( _ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath ) { guard collectionView.cellForItem(at: indexPath) is CollectionViewCell else { return } // My action for selecting cell print("Cell Selected") } }

I'm trying to determine if it’s possible to detect when a user interacts with a Slide Over window while my app is running in the background on iPadOS. I've explored lifecycle methods such as scenePhase and various UIApplication notifications (e.g., willResignActiveNotification) to detect focus loss, but these approaches don't seem to capture the event reliably. Has anyone found an alternative solution or workaround for detecting this specific state change? Any insights or recommended practices would be greatly appreciated.

My assumption has always been that [NSApp runModalForWindow:] runs a modal window in NSModalPanelRunLoopMode. However, while -[NSApplication _doModalLoop:peek:] seems to use NSModalPanelRunLoopMode when pulling out the next event to process via nextEventMatchingMask:untilDate:inMode:dequeue:, the current runloop doesn't seem to be running in that mode, so during -[NSApplication(NSEventRouting) sendEvent:] of the modal-specific event, NSRunLoop.currentRunLoop.currentMode returns kCFRunLoopDefaultMode. From what I can tell, this means that any event processing code that e.g. uses [NSTimer addTimer:forMode:] based on the current mode will register a timer that will not fire until the modal session ends. Is this a bug? Or if not, is the correct way to run a modal session something like this? [NSRunLoop.currentRunLoop performInModes:@[NSModalPanelRunLoopMode] block:^{ [NSApp runModalForWindow:window]; }]; [NSRunLoop.currentRunLoop limitDateForMode:NSModalPanelRunLoopMode]; Alternatively, if the mode of the runloop should stay the same, I've seen suggestions to run modal sessions like this: NSModalSession session = [NSApp beginModalSessionForWindow:theWindow]; for (;;) { if ([NSApp runModalSession:session] != NSModalResponseContinue) break; [NSRunLoop.currentRunLoop limitDateForMode:NSModalPanelRunLoopMode]; } [NSApp endModalSession:session]; Which would work around the fact that the timer/callbacks were scheduled in the "wrong" mode. But running NSModalPanelRunLoopMode during a modal session seems a bit scary. Won't that potentially break the modality?

Hi! I am having issues with my internal testing app now showing up the same through different users devices?

Could an Apple employee that works on SwiftUI please explain the update() func in the DynamicProperty protocol? The docs have ambiguous information, e.g. "Updates the underlying value of the stored value." and "SwiftUI calls this function before rendering a view’s body to ensure the view has the most recent value." From: https://developer.apple.com/documentation/swiftui/dynamicproperty/update() How can it both set the underlying value and get the most recent value? What does underlying value mean? What does stored value mean? E.g. Is the code below correct? struct MyProperty: DynamicProperty { var x = 0 mutating func update() { // get x from external storage x = storage.loadX() } } Or should it be: struct MyProperty: DynamicProperty { let x: Int init(x: Int) { self.x = x } func update() { // set x on external storage storage.save(x: x) } } This has always been a mystery to me because of the ambigious docs so thought it was time to post a question.

I have a custom keypad to accept numeric input for iPads that I have been using for many years now. This is longstanding working code. With iOS 18 the touchUpInside (and other) events in the underlying Objective-C modules are not called in the file owner module when activated from the interface. The buttons seem to be properly activated based on the visual cues (they change colors when pressed). This is occurring in both simulators and on hardware. Setting the target OS version does not help. What could the cause and/or solution of this be?

Our MacOS app has for some time been able to create so-called "add-on" services, which are dynamically written to individual bundles in ~/Library/Services/ (as opposed to being statically defined in the app's Info.plist). These worked fine for a long time until recently. They still appear in other app Services menus, but do not get as far as calling the specified instance method in our app. Does anyone know if add-on services are no longer supported? Perhaps due to some new security constraint? The documentation on app services in general seems to be out of date. I did try copying the add-on service definition from the add-on plist into the app's Info.plist. That seemed to work, so the basic specification doesn't seem to have changed.

How should I program the globe key? If possible, could you teach me in C language?

Hey, Anyone knows of a possible way to present a PasteButton in a .confirmationDialog on iOS? when I try adding it, it's ignored and not displayed with the rest of the buttons struct MyView: View { @State var flag: Bool = false var body: some View { Text("Some Text") .confirmationDialog("Dialog", isPresented: $flag) { Group { Button("A") {} Button("B") {} PasteButton(payloadType: Data.self) { data in } } } } }

I want to truncate text from head with max 2 lines. I try the following code import SwiftUI struct ContentView: View { @State var content: String = "Hello world! wef wefwwfe wfewe weweffwefwwfwe wfwe" var body: some View { VStack { Text(content) .lineLimit(nil) .truncationMode(.head) .frame(height: 50) Button { content += content } label: { Text("Double") } .buttonStyle(.borderedProminent) } .frame(width: 200, height: 1000) .padding() } } #Preview { ContentView() } It show result like this, this is not what I want.

I'm trying to make the side bar menu on my tvOS app have the same behavior of Apple's tvOS App. I would like to have the side menu collapsed at the cold start of the app. I'm trying to achieve this by using the defaultFocus view modifier, which should make the button inside the TabView focused at the start of the app. But no matter what I do, the side bar always steels the focus from the inside button. struct ContentView: View { enum Tabs { case viewA case viewB } enum ScreenElements { case button case tab } @FocusState private var focusedElement: ScreenElements? @State private var selectedTab: Tabs? = nil var body: some View { Group { TabView(selection: $selectedTab) { Tab("View A", image: "square", value: .viewA) { Button("View A Button", action: {}) .frame(maxWidth: .infinity, alignment: .center) .focused($focusedElement, equals: .button) } } .tabViewStyle(.sidebarAdaptable) .focused($focusedElement, equals: .tab) } .defaultFocus($focusedElement, .button, priority: .userInitiated) } } Is there a way to start the side bar menu collapsed at the start up of the app?

Hello, I’m developing an app where I display a SwiftUI view inside a UIHostingController embedded within a UIKit ViewController. I’m trying to animate the height of the UIHostingController’s view based on a switch’s value, but the SwiftUI view doesn’t animate at all. Below is a simplified version of my code: class ViewController: UIViewController { private lazy var parentView: UIView = { let view = UIView() view.backgroundColor = .red view.translatesAutoresizingMaskIntoConstraints = false return view }() private lazy var hostingView: UIView = { let testView = TestView() let hostingController = UIHostingController(rootView: testView) let view = hostingController.view! view.translatesAutoresizingMaskIntoConstraints = false return view }() private lazy var button: UISwitch = { let button = UISwitch() button.addTarget(self, action: #selector(onClickSwitch(sender:)), for: .valueChanged) button.translatesAutoresizingMaskIntoConstraints = false return button }() private var hostingViewHeightConstraint: NSLayoutConstraint? override func viewDidLoad() { super.viewDidLoad() view.addSubview(parentView) parentView.addSubview(hostingView) parentView.addSubview(button) NSLayoutConstraint.activate([ parentView.topAnchor.constraint(equalTo: view.topAnchor), parentView.bottomAnchor.constraint(equalTo: view.bottomAnchor), parentView.leadingAnchor.constraint(equalTo: view.leadingAnchor), parentView.trailingAnchor.constraint(equalTo: view.trailingAnchor) ]) NSLayoutConstraint.activate([ hostingView.bottomAnchor.constraint(equalTo: parentView.bottomAnchor), hostingView.leadingAnchor.constraint(equalTo: parentView.leadingAnchor), hostingView.trailingAnchor.constraint(equalTo: parentView.trailingAnchor) ]) hostingViewHeightConstraint = hostingView.heightAnchor.constraint(equalTo: parentView.heightAnchor, multiplier: 0.5) hostingViewHeightConstraint?.isActive = true NSLayoutConstraint.activate([ button.centerXAnchor.constraint(equalTo: parentView.centerXAnchor), NSLayoutConstraint(item: button, attribute: .centerY, relatedBy: .equal, toItem: parentView, attribute: .centerY, multiplier: 0.25, constant: 0) ]) } @objc func onClickSwitch(sender: UISwitch) { hostingViewHeightConstraint?.isActive = false let multiplier: CGFloat = sender.isOn ? 0.25 : 0.5 hostingViewHeightConstraint = hostingView.heightAnchor.constraint(equalTo: parentView.heightAnchor, multiplier: multiplier) hostingViewHeightConstraint?.isActive = true UIView.animate(withDuration: 0.3) { self.view.layoutIfNeeded() } } } I’m looking for the behavior demonstrated in the video below: Does anyone have suggestions on how to achieve this?

I set the isHidden property of a view in traitCollectionDidChange and found that sometime it does not take effect after being set(value of isHidden actually not changed either). It looks like the setting does not take effect when triggered an even number of times, but it is normal when triggered an odd number of times. When setting isHidden, what actually goes into is [UIView (Rendering) setHidden:], which internally calls [UIView _ bitFlagValueAfterIncrementingHiddenManagement CountForKey: withIncrement: bitFlagValue:] to handle the relevant logic of "_UIViewPendingHiddenCount". Is this issue related to this part of the processing? returning 0 after calling seems normal This view is a UIStackView, and it is uncertain whether it is related to the type of view

In our application we have two usecases for a Hotkey/Shortcut identification API/method. We have some predefined shortcuts that will ship with our MacOS application. They may or may not change dynamically, based on what the user has already set as shortcuts/hotkeys, and also to avoid any important system wide shortcuts that the user may or may not have changed. We allow the user to customize the shortcuts/hotkeys in our application, so we want to show what shortcuts the user already has in use system-wide and across their OS experience. This gives rise to the need for an API that lets us know which shortcut/hotkeys are currently being used by the user and also the current system wide OS shortcuts in use. Please let me know if there are any APIs in AppKit or SwiftUI we can use for the above

As a starter for iOS programming, I want to get the touch’ x-y position on a SwiftUI view , what is the fastest way/api or the highest refresh rate to get the position . UItouch in UIkit ?or other api?