At WWDC25 we launched a new type of Lab event for the developer community - Group Labs. A Group Lab is a panel Q&A designed for a large audience of developers. Group Labs are a unique opportunity for the community to submit questions directly to a panel of Apple engineers and designers. Here are the highlights from the WWDC25 Group Lab for UI Frameworks. How would you recommend developers start adopting the new design? Start by focusing on the foundational structural elements of your application, working from the "top down" or "bottom up" based on your application's hierarchy. These structural changes, like edge-to-edge content and updated navigation and controls, often require corresponding code modifications. As a first step, recompile your application with the new SDK to see what updates are automatically applied, especially if you've been using standard controls. Then, carefully analyze where the new design elements can be applied to your UI, paying particular attention to custom controls or UI that could benefit from a refresh. Address the large structural items first then focus on smaller details is recommended. Will we need to migrate our UI code to Swift and SwiftUI to adopt the new design? No, you will not need to migrate your UI code to Swift and SwiftUI to adopt the new design. The UI frameworks fully support the new design, allowing you to migrate your app with as little effort as possible, especially if you've been using standard controls. The goal is to make it easy to adopt the new design, regardless of your current UI framework, to achieve a cohesive look across the operating system. What was the reason for choosing Liquid Glass over frosted glass, as used in visionOS? The choice of Liquid Glass was driven by the desire to bring content to life. The see-through nature of Liquid Glass enhances this effect. The appearance of Liquid Glass adapts based on its size; larger glass elements look more frosted, which aligns with the design of visionOS, where everything feels larger and benefits from the frosted look. What are best practices for apps that use customized navigation bars? The new design emphasizes behavior and transitions as much as static appearance. Consider whether you truly need a custom navigation bar, or if the system-provided controls can meet your needs. Explore new APIs for subtitles and custom views in navigation bars, designed to support common use cases. If you still require a custom solution, ensure you're respecting safe areas using APIs like SwiftUI's safeAreaInset. When working with Liquid Glass, group related buttons in shared containers to maintain design consistency. Finally, mark glass containers as interactive. For branding, instead of coloring the navigation bar directly, consider incorporating branding colors into the content area behind the Liquid Glass controls. This creates a dynamic effect where the color is visible through the glass and moves with the content as the user scrolls. I want to know why new UI Framework APIs aren’t backward compatible, specifically in SwiftUI? It leads to code with lots of if-else statements. Existing APIs have been updated to work with the new design where possible, ensuring that apps using those APIs will adopt the new design and function on both older and newer operating systems. However, new APIs often depend on deep integration across the framework and graphics stack, making backward compatibility impractical. When using these new APIs, it's important to consider how they fit within the context of the latest OS. The use of if-else statements allows you to maintain compatibility with older systems while taking full advantage of the new APIs and design features on newer systems. If you are using new APIs, it likely means you are implementing something very specific to the new design language. Using conditional code allows you to intentionally create different code paths for the new design versus older operating systems. Prefer to use if #available where appropriate to intentionally adopt new design elements. Are there any Liquid Glass materials in iOS or macOS that are only available as part of dedicated components? Or are all those materials available through new UIKit and AppKit views? Yes, some variations of the Liquid Glass material are exclusively available through dedicated components like sliders, segmented controls, and tab bars. However, the "regular" and "clear" glass materials should satisfy most application requirements. If you encounter situations where these options are insufficient, please file feedback. If I were to create an app today, how should I design it to make it future proof using Liquid Glass? The best approach to future-proof your app is to utilize standard system controls and design your UI to align with the standard system look and feel. Using the framework-provided declarative API generally leads to easier adoption of future design changes, as you're expressing intent rather than specifying pixel-perfect visuals. Pay close attention to the design sessions offered this year, which cover the design motivation behind the Liquid Glass material and best practices for its use. Is it possible to implement your own sidebar on macOS without NSSplitViewController, but still provide the Liquid Glass appearance? While technically possible to create a custom sidebar that approximates the Liquid Glass appearance without using NSSplitViewController, it is not recommended. The system implementation of the sidebar involves significant unseen complexity, including interlayering with scroll edge effects and fullscreen behaviors. NSSplitViewController provides the necessary level of abstraction for the framework to handle these details correctly. Regarding the SceneDelagate and scene based life-cycle, I would like to confirm that AppDelegate is not going away. Also if the above is a correct understanding, is there any advice as to what should, and should not, be moved to the SceneDelegate? UIApplicationDelegate is not going away and still serves a purpose for application-level interactions with the system and managing scenes at a higher level. Move code related to your app's scene or UI into the UISceneDelegate. Remember that adopting scenes doesn't necessarily mean supporting multiple scenes; an app can be scene-based but still support only one scene. Refer to the tech note Migrating to the UIKit scene-based life cycle and the Make your UIKit app more flexible WWDC25 session for more information.

Here’s a recap of the Live Q&A for SwiftUI foundations: Build great apps with SwiftUI. If you participated and asked questions, thank you for coming and participating! If you weren’t able to join us live we hope this recap is useful Where can I watch the VOD? Is the sample code “Wishlist” that was shown available for download? You can view the replay of the entire event here https://www.youtube.com/watch?v=Z3vloOtZLkQ The sample code for the Wishlist app will be made available in the coming weeks on the Apple Developer website, we'll send an update via email when it is available. What are the best practices when it comes to building complex navigations in SwiftUI? The developer website has documentation on navigation style best practices. Explore navigation basics like NavigationStack and TabView to get a ground-up understanding. For documentation on navigation APIs see Navigation. How can I integrate UIKit with my SwiftUI app? What about adding SwiftUI into my UIKit app? See UIKit integration: Add UIKit views to your SwiftUI app, or use SwiftUI views in your UIKit app. Both UIKit and SwiftUI provide API to show a view hierarchy of the other. For UIKit to SwiftUI, you would use UIViewControllerRepresentable. For SwiftUI to UIKit, you would use UIHostingController. Landmarks: Interfacing with UIKit walks you through step by step how to implement UIKit in SwiftUI with UIViewControllerRepresentable, and this WWDC22 video demonstrates UIHostingController, for those that want to add SwiftUI to their UIKit. Does Wishlist feature a new iOS 26 font? How can I add custom fonts and text of my app? We’re glad to hear many of you liked wide text shown in Wishlist, however, It is the default system font with some light SwiftUI styling! Check it out for yourself in the sample code when made available, and you can learn more about customizing fonts and text by seeing Font and Applying custom fonts to text. Does Xcode have a dependency graph we can use to optimize our SwiftUI Views? Xcode comes with Instruments. Instruments is the best way to figure out what is causing excessive updates and other issues with performance. That link provides direct tutorials and resources for how to use and understand. Previews also have many useful tools for analyzing SwiftUI views, for more info see Previews in Xcode Check out this video from our latest WWDC Optimize SwiftUI performance with Instruments for information on how to use Instruments to profile and optimize your app with real-world applications If you still have questions, Check out the Instruments section of these forums and create a post so the community has the opportunity to help guide you. Are there UI debugging tools to help diagnose layout issues? Yes, Xcode also features a View Debugger located by selecting the View Debug Hierarchy, pictured below. Use the View Debugger to capture and inspect your view hierarchy, identifying which views affect window sizing. The SwiftUI Inspector also lets you examine view frames and layout behavior. See Diagnosing issues in the appearance of a running app to learn about debugging visual and layout issues. As an absolute beginner, what would be the first go-to step to go for training? Do I need prior knowledge of frameworks to get started with SwiftUI? A great place to learn how to develop for Apple platforms is with Pathways! Many developers start with Develop in Swift tutorials, which exposes you to several frameworks while teaching you the basics of SwiftUI. When you're ready to take your learning further, you can read the documentation for the specific frameworks that interest you at https://developer.apple.com/documentation/.

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

I want record screen in my app,the method startCaptureWithHandler:completionHandler:,the sampleBuffer， It is supposed to exist but it has become nil.Not only that,but there‘s another problem,when I want to stop recording and save the video,I will check [RPScreenRecorder sharedRecorder].recording first, it will be false sometime,that problems are unusual in iOS 18.3.2 iPhoneXs Max,and unexpected,here is my code -(void)startCaptureScreen { NSLog(@"AKA++ startCaptureScreen"); if ([[RPScreenRecorder sharedRecorder] isRecording]) { return; } //屏幕录制 [[RPScreenRecorder sharedRecorder]setMicrophoneEnabled:YES]; NSLog(@"AKA++ MicrophoneEnabled AAAA startCaptureScreen"); [[RPScreenRecorder sharedRecorder]setCameraEnabled:YES]; [[RPScreenRecorder sharedRecorder] startCaptureWithHandler:^(CMSampleBufferRef _Nonnull sampleBuffer, RPSampleBufferType bufferType, NSError * _Nullable error) { if(self.assetWriter == nil){ if (self.AVAssetWriterStatus == 0) { [self setupAssetWriterAndStartWith:sampleBuffer]; } } if (self.AVAssetWriterStatus != 2) { return; } if (error) { // deal with error return; } if (self.assetWriter.status != AVAssetWriterStatusWriting) { [self assetWriterAppendSampleBufferFailWith:bufferType]; return; } if (bufferType == RPSampleBufferTypeVideo) { if(self.assetWriter.status == 0 ||self.assetWriter.status > 2){ } else if(self.videoAssetWriterInput.readyForMoreMediaData == YES){ BOOL success = [self.videoAssetWriterInput appendSampleBuffer:sampleBuffer]; } } if (bufferType == RPSampleBufferTypeAudioMic) { if(self.assetWriter.status == 0 ||self.assetWriter.status > 2){ } else if(self.audioAssetWriterInput.readyForMoreMediaData == YES){ BOOL success = [self.audioAssetWriterInput appendSampleBuffer:sampleBuffer]; } } } completionHandler:^(NSError * _Nullable error) { //deal with error }]; } and than ,when want to save it : -(void)stopRecording { if([[RPScreenRecorder sharedRecorder] isRecording]){ // The problem is sporadic,recording action failed,it makes me confused } [[RPScreenRecorder sharedRecorder] stopCaptureWithHandler:^(NSError * _Nullable error) { if(!error) { //post message } }]; }

Description: When initiating the print flow via UIPrintInteractionController, and no printer is initially connected, iOS displays all possible paper sizes in the paper selection UI. However, if a printer connects in the background after this view is shown, the list of paper sizes does not automatically refresh to reflect only the options supported by the connected printer. If the user selects an incompatible paper size (one not supported by the printer that has just connected), the app crashes due to an invalid configuration. Steps to Reproduce: Launch the app and navigate to the print functionality. Tap the Print button to invoke UIPrintInteractionController. At this point, no printer is yet connected. iOS displays all available paper sizes. While the paper selection UI is visible, the AirPrint-compatible printer connects in the background. Without dismissing the controller, the user selects a paper size (e.g., one that is not supported by the printer). The app crashes. Expected Result: App should not crash Once the printer becomes available (connected in the background), the paper size options should refresh automatically. The list should be filtered to only include sizes that are compatible with the connected printer. This prevents the user from selecting an invalid option, avoiding crashes. Actual Result: App crashes The paper size list remains unfiltered. The user can still select unsupported paper sizes. Selecting an incompatible option causes the app to crash, due to a mismatch between UI selection and printer capability.

Anybody can help me with the problems of splashboard? My request is to create a launchScreen.storyboard that can follows system's theme. So in the storyboard i use the image set resource which is created in Assets.xcassets. But i encountered the following problems： when i use image set resource，the splashboard is black, seems like springboard fail to generate the ktx file. But when i move the same image file to the root of Resource directory, it works. Why???? Some image works when it is put in Image set, some file can't. But all file don't work when the image set contains both light image and dark image. Why??? Suddenly it works for when i change compression attribute to lossess，so i guess the problems hanppened when my image is compressed. And two days later, the splash board is dark again when i debug. So what is the cache strategy for the splash board and the image resource used. How can i clear the cache, delete the app is not enough? Should i restart my phone? That's all, anybody can help me?

I set UIToolbar and UIBarButtonItem to UITextField placed on Xib, but when I run it on iOS18 iPad, the following error is output to Xcode Console, and UIPickerView set to UITextField.inputView is not displayed. Error: this application, or a library it uses, has passed an invalid numeric value (NaN, or not-a-number) to CoreGraphics API and this value is being ignored. Please fix this problem. If you want to see the backtrace, please set CG_NUMERICS_SHOW_BACKTRACE environmental variable. Backtrace: <CGPathAddLineToPoint+71> <+[UIBezierPath _continuousRoundedRectBezierPath:withRoundedCorners:cornerRadii:segments:smoothPillShapes:clampCornerRadii:] <+[UIBezierPath _continuousRoundedRectBezierPath:withRoundedCorners:cornerRadius:segments:]+175> <+[UIBezierPath _roundedRectBezierPath:withRoundedCorners:cornerRadius:segments:legacyCorners:]+338> <-[_UITextMagnifiedLoupeView layoutSubviews]+2233> <__56-[_UITextMagnifiedLoupeView _updateCloseLoupeAnimation:]_block_invoke+89> <+[UIView(UIViewAnimationWithBlocksPrivate) _modifyAnimationsWithPreferredFrameRateRange:updateReason:animations:]+166> <block_destroy_helper.269+92> <block_destroy_helper.269+92> <__swift_instantiateConcreteTypeFromMangledName+94289> <block_destroy_helper.269+126> <+[UIView(UIViewAnimationWithBlocks) _setupAnimationWithDuration:delay:view:options:factory:animations:start:anima <block_destroy_helper.269+6763> <block_destroy_helper.269+10907> <-[_UITextMagnifiedLoupeView _updateCloseLoupeAnimation:]+389> <-[_UITextMagnifiedLoupeView setVisible:animated:completion:]+256> <-[UITextLoupeSession _invalidateAnimated:]+329> <-[UITextRefinementTouchBehavior textLoupeInteraction:gestureChangedWithState:location:translation:velocity: <-[UITextRefinementInteraction loupeGestureWithState:location:translation:velocity:modifierFlags:shouldCanc <-[UITextRefinementInteraction loupeGesture:]+701> <-[UIGestureRecognizerTarget _sendActionWithGestureRecognizer:]+71> <_UIGestureRecognizerSendTargetActions+100> <_UIGestureRecognizerSendActions+306> <-[UIGestureRecognizer _updateGestureForActiveEvents]+704> <_UIGestureEnvironmentUpdate+3892> <-[UIGestureEnvironment _updateForEvent:window:]+847> <-[UIWindow sendEvent:]+4937> <-[UIApplication sendEvent:]+525> <__dispatchPreprocessedEventFromEventQueue+1436> <__processEventQueue+8610> <updateCycleEntry+151> <_UIUpdateSequenceRun+55> <schedulerStepScheduledMainSection+165> <runloopSourceCallback+68> <__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__+17> <__CFRunLoopDoSource0+157> <__CFRunLoopDoSources0+293> <__CFRunLoopRun+960> <CFRunLoopRunSpecific+550> <GSEventRunModal+137> <-[UIApplication _run]+875> <UIApplicationMain+123> <__debug_main_executable_dylib_entry_point+63> 10d702478 204e57345 Type: Error | Timestamp: 2025-03-09 00:22:46.121407+09:00 | Process: FurusatoLocalCurrency | Library: CoreGraphics | Subsystem: com.apple.coregraphics | Category: Unknown process name | TID: 0x5c360 Unable to simultaneously satisfy constraints. Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) ( "<NSAutoresizingMaskLayoutConstraint:0x600002202a30 h=--& v=--& _UIToolbarContentView:0x7fc2c6a5b8f0.width == 0 (active)>", "<NSLayoutConstraint:0x600002175e00 H:|-(0)-[_UIButtonBarStackView:0x7fc2c6817b10] (active, names: '|':_UIToolbarContentView:0x7fc2c6a5b8f0 )>", "<NSLayoutConstraint:0x600002175e50 H:[_UIButtonBarStackView:0x7fc2c6817b10]-(0)-| (active, names: '|':_UIToolbarContentView:0x7fc2c6a5b8f0 )>", "<NSLayoutConstraint:0x6000022019f0 'TB_Leading_Leading' H:|-(8)-[_UIModernBarButton:0x7fc2a5aa8920] (active, names: '|':_UIButtonBarButton:0x7fc2a5aa84d0 )>", "<NSLayoutConstraint:0x600002201a40 'TB_Trailing_Trailing' H:[_UIModernBarButton:0x7fc2a5aa8920]-(0)-| (active, names: '|':_UIButtonBarButton:0x7fc2a5aa84d0 )>", "<NSLayoutConstraint:0x600002201e50 'UISV-canvas-connection' UILayoutGuide:0x600003b7d420'UIViewLayoutMarginsGuide'.leading == _UIButtonBarButton:0x7fc2f57117f0.leading (active)>", "<NSLayoutConstraint:0x600002201ea0 'UISV-canvas-connection' UILayoutGuide:0x600003b7d420'UIViewLayoutMarginsGuide'.trailing == UIView:0x7fc2a5aac8e0.trailing (active)>", "<NSLayoutConstraint:0x6000022021c0 'UISV-spacing' H:[_UIButtonBarButton:0x7fc2f57117f0]-(0)-[UIView:0x7fc2a5aa8330] (active)>", "<NSLayoutConstraint:0x600002202210 'UISV-spacing' H:[UIView:0x7fc2a5aa8330]-(0)-[_UIButtonBarButton:0x7fc2a5aa84d0] (active)>", "<NSLayoutConstraint:0x600002202260 'UISV-spacing' H:[_UIButtonBarButton:0x7fc2a5aa84d0]-(0)-[UIView:0x7fc2a5aac8e0] (active)>", "<NSLayoutConstraint:0x600002176f30 'UIView-leftMargin-guide-constraint' H:|-(0)-[UILayoutGuide:0x600003b7d420'UIViewLayoutMarginsGuide'](LTR) (active, names: '|':_UIButtonBarStackView:0x7fc2c6817b10 )>", "<NSLayoutConstraint:0x600002176e40 'UIView-rightMargin-guide-constraint' H:[UILayoutGuide:0x600003b7d420'UIViewLayoutMarginsGuide']-(0)-|(LTR) (active, names: '|':_UIButtonBarStackView:0x7fc2c6817b10 )>" ) Will attempt to recover by breaking constraint <NSLayoutConstraint:0x600002201a40 'TB_Trailing_Trailing' H:[_UIModernBarButton:0x7fc2a5aa8920]-(0)-| (active, names: '|':_UIButtonBarButton:0x7fc2a5aa84d0 )> Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger. The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKitCore/UIView.h> may also be helpful.

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)

App update in which there were no changes regarding the widget. Just after it updated, the widget turns black in some cases. It also appears black in the widget gallery. Removing and adding it again did not work in this case, only after an iOS restart it works fine again This is the log 2025-03-20 02:14:05.961611 +0800 Content load failed: unable to find or unarchive file for key: [com.aa.bb::com.aa.bb.widget:cc_widget:systemMedium::360.00/169.00/23.00:(null)~(null)] on no host. The session may still produce one shortly. Error: Using url file:///private/var/mobile/Containers/Data/PluginKitPlugin/51C5E4F2-6F1F-4466-A428-73C73B9CC887/SystemData/com.apple.chrono/placeholders/cc_widget/systemMedium----360.00w--169.00h--23.00r--1f--0.00t-0.00l-0.00b0.00t.chrono-timeline ... Error Domain=NSCocoaErrorDomain Code=4 "file“systemMedium----360.00w--169.00h--23.00r--1f--0.00t-0.00l-0.00b0.00t.chrono-timeline”not exist。" UserInfo={NSFilePath=/private/var/mobile/Containers/Data/PluginKitPlugin/51C5E4F2-6F1F-4466-A428-73C73B9CC887/SystemData/com.apple.chrono/placeholders/cc_widget/systemMedium----360.00w--169.00h--23.00r--1f--0.00t-0.00l-0.00b0.00t.chrono-timeline, NSUnderlyingError=0xa693d3a80 {Error Domain=NSPOSIXErrorDomain Code=2 "No such file or directory"}}

I am currently developing an AR experience using ARKit with SceneKit and am looking to implement functionality that enables: Zooming into the AR camera feed, ideally leveraging the ultra-wide or telephoto lenses available on supported devices. Macro-style focus capabilities, allowing users to view and interact with virtual content closely aligned with small or nearby real-world objects (within a few centimeters). My objective is to ensure that ARKit continues to render the scene accurately while enabling a zoomed-in view or macro-level focus for better detail visibility and alignment. Could you please advise on: Whether ARKit currently supports camera zoom or allows access to macro or ultra-wide cameras within an ARSession. Limitations or considerations when using multi-camera setups in conjunction with ARKit. Any guidance or references to documentation or sample code would be greatly appreciated. Best regards, Ayush

DESCRIPTION OF PROBLEM We need to add an implementation that will have the same swipe/scroll behavior as the Apple Translator extension, here is the code that we are currently using: import SwiftUI import TranslationUIProvider @main class TranslationProviderExtension: TranslationUIProviderExtension { required init() {} var body: some TranslationUIProviderExtensionScene { TranslationUIProviderSelectedTextScene { context in VStack { TranslationProviderView(context: context) } } } } struct TranslationProviderView: View { @State var context: TranslationUIProviderContext init(context c: TranslationUIProviderContext) { context = c } var body: some View { ScrollableSheetView() } } struct ScrollableSheetView: View { var body: some View { ScrollView { VStack(spacing: 20) { ForEach(0..<50) { index in Text("Item (index)") .padding() .frame(maxWidth: .infinity) .background(Color.blue.opacity(0.1)) .cornerRadius(8) } } .padding() } .padding() } } Using this code, on the first extension run, swipe up will expand the extension (which is OK) but swiping down on the expanded state of the extension works only as a scroll instead of swiping the extension from expanded mode back to compact mode. STEPS TO REPRODUCE Select a text in Safari Tap on Translate in the contextual menu Swipe up on the text ->the extension expands into full mode Swipe down->only scrolls work, I cannot swipe the extension from full mode to compact mode. Expected behavior: when i swipe down on the expanded extension, the extension should get into compact mode, not continuously scroll down.

For now, my app name length is more than 20 characters, so the iPhone app name displays without a space, and uses the range operator to ensure showing the rest in the next line. Is it possible to show space and name with 2 lines?

I'm currently integrating SwiftUI into an AppKit based application and was curious if the design pattern below was viable or not. In order to "bridge" between AppKit and SwiftUI, most of my SwiftUI "root" views have aViewModel that is accessible to the SwiftUI view via @ObservedObject. When a SwiftUI views need to use NSViewRepresentable I'm finding the use of a ViewModel and a Coordinator to be an unnecessary layer of indirection. In cases where it makes sense, I've just used the ViewModel as the Coordinator and it all appears to be working ok, but I'm curious if this is reasonable design pattern or if I'm overlooking something. Consider the following pseudo code: // 1. A normal @ObservedObject acting as the ViewModel that also owns and manages an NSTableView. @MainActor final class ViewModel: ObservedObject, NSTableView... { let scrollView: NSScrollView let tableView: NSTableView @Published var selectedTitle: String init() { // ViewModel manages tableView as its dataSource and delegate. tableView.dataSource = self tableView.delegate = self } func reload() { tableView.reloadData() } // Update view model properties. // Simpler than passing back up through a Coordinator. func tableViewSelectionDidChange(_ notification: Notification) { selectedTitle = tableView.selectedItem.title } } // 2. A normal SwiftUI view, mostly driven by the ViewModel. struct ContentView: View { @ObservedObject model: ViewModel var body: some View { Text(model.selectedTitle) // No need to pass anything down other than the view model. MyTableView(model: model) Button("Reload") { model.reload() } Button("Delete") { model.deleteRow(...) } } } // 3. A barebones NSViewRepresentable that just vends the required NSView. No other state is required as the ViewModel handles all interactions with the view. struct MyTableView: NSViewRepresentable { // Can this even be an NSView? let model: ViewModel func makeNSView(context: Context) -> some NSView { return model.scrollView } func updateNSView(_ nsView: NSViewType, context: Context) { // Not needed, all updates are driven through the ViewModel. } } From what I can tell, the above is working as expected, but I'm curious if there are some situations where this could "break", particularly around the lifecycle of NSViewRepresentable Would love to know if overall pattern is "ok" from a SwiftUI perspective.

I have a DocumentGroup working with a FileDocument, and that's fine. However, when someone creates a new document I want them to have to immediately save it. This is the behavior on ipadOS and iOS from what I can understand (you select where before the file is created). There seems to be no way to do this on macOS? I basically want to have someone: create a new document enter some basic data hit "create" which saves the file then lets the user start editing it (1), (2), and (4) are done and fairly trivial. (3) seems impossible, though...? This really only needs to support macOS but any pointers would be appreciated.

iOS 18.4.1 When I change a Google type event to an iCloud type, a "Cannot Save Event" prompt box pops up. We have also received user feedback that recurring events also fail to save. After updating to iOS 18.4 when trying to save changes to an existing repeating event, the message "Cannot Save Event" will appear. EventKitUI

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 Team! Has anyone found a reliable way to detect CarPlay connection without the app needing to be in the foreground? I’m exploring a concept where, for example, as someone nears home while driving, a prompt appears on the CarPlay screen asking “Would you like to turn on the lights / open garage?” triggered by proximity and CarPlay connection. Would be cool to have it work automatically, but knowing you're in the car is kind of important. From what I can see, apps can’t reliably detect CarPlay connection unless they’re actively open on the CarPlay screen. Most background detection methods (like external screen connect notifications) appear deprecated. That is, unless you're specifically approved as a "messaging" or "navigation" app that appear to get special privilages to send alerts from the background. If I send an alert (or poll Carplay periodically) it just gives silent/dead response. Is there any approach, framework, entitlement, or UI pattern that could allow a passive trigger or background detection while driving with CarPlay connected? I can't see any way to bring an app to the foreground either. Not looking to abuse any rules... just want to understand if anyone’s found a clean, approved workaround. Thanks in advance!

We've seen a spike in crashes on iOS 18.4 across both iPhone & iPad. We can't reproduce it, but it looks like it happens when the app goes into the background. Crash Log

I am attempting to start my application on iOS 26 with Xcode 26. It uses an UISplitViewController that is instantiated through a Storyboard. It uses the "Unspecified" style, which is a holdover from a previous version of iOS. I'm not sure if this is a bug in iOS, or if I am supposed to change it now. The viewControllers property only has the primary view controller on iOS, although it has the primary and detail view controllers on iPadOS. When I start the application on iOS 18.5, it has both primary and detail controllers on both platforms.

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, I've got an app that displays markdown in UITextView / NSTextView. I would like it to behave like Notes app does, that is if user types the line start modifier, e.g: "# " or "> " I would like the keyboard to show a capitalized letters. I've tried looking into overriding insertText - and it breaks the predictive text (can not insert white space). I've tried implementing UITextInputTokenizer but no luck either. Like I said, I see the Notes app does it perfectly, so maybe I'm missing something obvious or there is a way to do it without interrupting the auto-correction and predictive text. Ideally same thing can be applied to the NSTextView as the app support both platforms.

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 } } } } }