Explore the various UI frameworks available for building app interfaces. Discuss the use cases for different frameworks, share best practices, and get help with specific framework-related questions.

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DocumentGroupLaunchScene corrupts the toolbar for DocumentGroup content views.
The sample code provided in "Building a document-based app with SwiftUI" (https://developer.apple.com/documentation/swiftui/building-a-document-based-app-with-swiftui) does not work as expected. The DocumentGroup/StoryView toolbar does not appear for documents opened in the App. By removing the DocumentGroupLaunchScene block from the App the toolbar does appear and works as expected - but of course the App's DocumentGroupLaunchScene customizations are lost. I've tested this on 18.0 devices, as well as production 18.0 and 18.1 beta 6 simulators. If I modify the StoryView by wrapping the content in a NavigationStack I can make some progress - but the results are unstable and hard to pin down - with this change the first time a document is opened in the WritingApp the toolbar appears as expected. When opening a document subsequently the toolbar is corrupted. Please is this a bug or is there a good example of incorporate both DocumentGroupLaunchScene customizations at the App level and retina the toolbar in documents presented via DocumentGroup?
Topic: UI Frameworks SubTopic: SwiftUI
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662
May ’25
Source view disappearing when interrupting a zoom navigation transition
When I use the .zoom transition in a navigation stack, I get a glitch when interrupting the animation by swiping back before it completes. When doing this, the source view disappears. I can still tap it to trigger the navigation again, but its not visible on screen. This seems to be a regression in iOS 26, as it works as expected when testing on iOS 18. Has someone else seen this issue and found a workaround? Is it possible to disable interrupting the transition? Filed a feedback on the issue FB19601591 Screen recording: https://share.icloud.com/photos/04cio3fEcbR6u64PAgxuS2CLQ Example code @State var showDetail = false @Namespace var namespace var body: some View { NavigationStack { ScrollView { showDetailButton } .navigationTitle("Title") .navigationBarTitleDisplayMode(.inline) .navigationDestination(isPresented: $showDetail) { Text("Detail") .navigationTransition(.zoom(sourceID: "zoom", in: namespace)) } } } var showDetailButton: some View { Button { showDetail = true } label: { Text("Show detail") .padding() .background(.green) .matchedTransitionSource(id: "zoom", in: namespace) } } }
Topic: UI Frameworks SubTopic: SwiftUI
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16
865
Nov ’25
UITabBarController crashes when editing the items
I'm using one UITabBarController which leads to 6 NavigationController. Therefore the user will get 4 icons displayed and one icon with three points to see the rest of the Navigation Controller. If the user now tries to edit the list and moves one item from the hidden area towards the TabBar at the bottom, the App crashes with the error: Exception NSException * "Can't add self as subview" 0x0000600000d16040 I can see this effect at least on both my apps. If the same compilation is run on a older iOS version, there is no crash. Is there anything I have to take care of the configuration of the TabBar, when it comes to iOS26?
Topic: UI Frameworks SubTopic: UIKit
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3w
iOS 26 UIKIt: Where's the missing cornerConfiguration property of UIViewEffectView?
In WWDC25 video 284: Build a UIKit app with the new design, there is mention of a cornerConfiguration property on UIVisualEffectView. But this properly isn't documented and Xcode 26 isn't aware of any such property. I'm trying to replicate the results of that video in the section titled Custom Elements starting at the 19:15 point. There is a lot of missing details and typos in the code associated with that video. My attempts with UIGlassEffect and UIViewEffectView do not result in any capsule shapes. I just get rectangles with no rounded corners at all. As an experiment, I am trying to recreate the capsule with the layers/location buttons in the iOS 26 version of the Maps app. I put the following code in a view controller's viewDidLoad method let imgCfgLayer = UIImage.SymbolConfiguration(hierarchicalColor: .systemGray) let imgLayer = UIImage(systemName: "square.2.layers.3d.fill", withConfiguration: imgCfgLayer) var cfgLayer = UIButton.Configuration.plain() cfgLayer.image = imgLayer let btnLayer = UIButton(configuration: cfgLayer, primaryAction: UIAction(handler: { _ in print("layer") })) var cfgLoc = UIButton.Configuration.plain() let imgLoc = UIImage(systemName: "location") cfgLoc.image = imgLoc let btnLoc = UIButton(configuration: cfgLoc, primaryAction: UIAction(handler: { _ in print("location") })) let bgEffect = UIGlassEffect() bgEffect.isInteractive = true let bg = UIVisualEffectView(effect: bgEffect) bg.contentView.addSubview(btnLayer) bg.contentView.addSubview(btnLoc) view.addSubview(bg) btnLayer.translatesAutoresizingMaskIntoConstraints = false btnLoc.translatesAutoresizingMaskIntoConstraints = false bg.translatesAutoresizingMaskIntoConstraints = false NSLayoutConstraint.activate([ btnLayer.leadingAnchor.constraint(equalTo: bg.contentView.leadingAnchor), btnLayer.trailingAnchor.constraint(equalTo: bg.contentView.trailingAnchor), btnLayer.topAnchor.constraint(equalTo: bg.contentView.topAnchor), btnLoc.centerXAnchor.constraint(equalTo: bg.contentView.centerXAnchor), btnLoc.topAnchor.constraint(equalTo: btnLayer.bottomAnchor, constant: 15), btnLoc.bottomAnchor.constraint(equalTo: bg.contentView.bottomAnchor), bg.centerXAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor), bg.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor, constant: 40), ]) The result is pretty close other than the complete lack of capsule shape. What changes would be needed to get the capsule shape? Is this even the proper approach?
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763
Sep ’25
iOS 18 beta bug: NavigationStack pushes the same view twice
Hello, community and Apple engineers. I need your help. Our app has the following issue: NavigationStack pushes a view twice if the NavigationStack is inside TabView and NavigationStack uses a navigation path of custom Hashable elements. Our app works with issues in Xcode 18 Beta 13 + iOS 18.0. The same issue happened on previous beta versions of Xcode 18. The issue isn’t represented in iOS 17.x and everything worked well before iOS 18.0 beta releases. I was able to represent the same issue in a clear project with two simple views. I will paste the code below. Several notes: We use a centralised routing system in our app where all possible routes for navigation path are implemented in a View extension called withAppRouter(). We have a enum RouterDestination that contains all possible routes and is resolved in withAppRouter() extension. We use Router class that contains @Published var path: [RouterDestination] = [] and this @Published property is bound to NavigationStack. In the real app, we need to have an access to this path property for programmatic navigation purposes. Our app uses @ObservableObject / @StateObject approach. import SwiftUI struct ContentView: View { @StateObject private var router = Router() var body: some View { TabView { NavigationStack(path: $router.path) { NavigationLink(value: RouterDestination.next, label: { Label("Next", systemImage: "plus.circle.fill") }) .withAppRouter() } } } } enum RouterDestination: Hashable { case next } struct SecondView: View { var body: some View { Text("Screen 2") } } class Router: ObservableObject { @Published var path: [RouterDestination] = [] } extension View { func withAppRouter() -> some View { navigationDestination(for: RouterDestination.self) { destination in switch destination { case .next: return SecondView() } } } } Below you can see the GIF with the issue: What I tried to do: Use iOS 17+ @Observable approach. It didn’t help. Using @State var path: [RouterDestination] = [] directly inside View seems to help. But it is not what we want as we need this property to be @Published and located inside Router class where we can get an access to it, and use for programmatic navigation if needed. I ask Apple engineers to help with that, please, and if it is a bug of iOS 18 beta, then please fix it in the next versions of iOS 18.0
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1.9k
Jun ’25
PHPickerViewController unusable via Mac Catalyst on macOS 26 when interface is "Scaled to Match iPad"
There is a serious usability issue with PHPickerViewController in a UIKit app running on macOS 26 via Mac Catalyst when the Mac Catalyst interface is set to “Scaled to Match iPad”. Mouse click and other pointer interactions do not take place in the correct position. This means you have to click in the wrong position to select a photo and to close the picker. This basically makes it unusable. To demonstrate, use Xcode 26 on macOS 26 to create a new iOS app project based on Swift/Storyboard. Then update ViewController.swift with the following code: import UIKit import PhotosUI class ViewController: UIViewController { override func viewDidLoad() { super.viewDidLoad() var cfg = UIButton.Configuration.plain() cfg.title = "Photo Picker" let button = UIButton(configuration: cfg, primaryAction: UIAction(handler: { _ in self.showPicker() })) button.translatesAutoresizingMaskIntoConstraints = false view.addSubview(button) NSLayoutConstraint.activate([ button.centerXAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor), button.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor), ]) } private func showPicker() { var config = PHPickerConfiguration() config.selectionLimit = 10 config.selection = .ordered let vc = PHPickerViewController(configuration: config) vc.delegate = self self.present(vc, animated: true) } } extension ViewController: PHPickerViewControllerDelegate { func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) { print("Picked \(results.count) photos") dismiss(animated: true) } } Then go to the "Supported Destinations" section of the project target. Add a "Mac (Mac Catalyst)" destination. Then under the "Deployment Information" section, make sure the "Mac Catalyst Interface" setting is "Scaled to Match iPad". Then build and run the app on a Mac (using the Mac Catalyst destination) with macOS 26.0.1. Make sure the Mac has a dozen or so pictures in the Photo Library to fully demonstrate the issue. When the app is run, a simple screen appears with one button in the middle. Click the button to bring up the PHPickerViewController. Now try to interact with the picker interface. Note that all pointer interactions are in the wrong place on the screen. This makes it nearly impossible to choose the correct photos and close the picker. Quit the app. Select the project and go to the General tab. In the "Deployment Info" change the “Mac Catalyst Interface” setting to “Optimize for Mac” and run the app again. Now the photo picker works just fine. If you run the app on a Mac running macOS 15 then the photo picker works just fine with either “Mac Catalyst Interface” setting. The problem only happens under macOS 26.0 (I do not have macOS 26.1 beta to test) when the “Mac Catalyst Interface” setting is set to “Scaled to Match iPad”. This is critical for my app. I cannot use “Optimize for Mac”. There are far too many issues with that setting (I use UIStepper and UIPickerView to start). So it is critical to the usability of my app under macOS 26 that this issue be resolved. It is expected that PHPickerViewController responds correctly to pointer events on macOS 26 when running a Mac Catalyst app set to “Scaled to Match iPad”. A version of this has been filed as FB20503207
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612
Oct ’25
SwiftUI Preview Runtime linking failure
I'm using GoogleMaps in my project. Legacy preview works well but new preview (Xcode 16.3.1 beta) produces error. It doesn't seem to find Googlemaps.a. == PREVIEW UPDATE ERROR: FailedToLaunchAppError: Failed to launch *** ================================== | [Remote] JITError | | ================================== | | | [Remote] CouldNotLoadInputStaticArchiveFile: Could not load static archive during preview: /Users/xxx/Library/Developer/Xcode/DerivedData/BOA-eiluspltxasszsfkpqrnnsxsjhth/Build/Products/Debug_BOA_Inhouse-iphonesimulator/GoogleMaps.a | | | | path: /Users/xxx/Library/Developer/Xcode/DerivedData/BOA-eiluspltxasszsfkpqrnnsxsjhth/Build/Products/Debug_BOA_Inhouse-iphonesimulator/GoogleMaps.a | | | | ================================== | | | | | [Remote] XOJITError | | | | | | XOJITError: arm64 slice of /Users/xxx/Library/Developer/Xcode/DerivedData/BOA-eiluspltxasszsfkpqrnnsxsjhth/Build/Products/Debug_BOA_Inhouse-iphonesimulator/GoogleMaps.a does not contain an archive
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0
1.2k
Jun ’25
Setting launch screen image through info.plist - image stretches to cover full screen
I am developing an app in swiftUI using Xcode 12.3, deployment target iOS 14.0. The launch screen is setup through info.plist by specifying 'background color' and 'image name'. The file used in 'image name' is from Assets catalog. (PNG format, size300 x 300 and corresponding @2x and @3x resolutions) What I have observed, when the app is installed for the first time the launch image is centered and have original resolutions but all subsequent launches show launch images stretched to cover full screen. Any ideas why this is happening and how to have more consistent behavior either way? I have tried 'respect safe area' option but it does not make a difference. Thank you.
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13k
Mar ’25
HELP: App Clip Card Doesn't Appear!
I integrated an Advanced App Clip Experience to my app. In trying to test the App Clip Card, the card does not appear when I tap the link on my device that is associated to the Advanced App Clip Experience. Listed are some contextual information: Testing on device running on iOS 18.3.1 Associated Domains: Main target app: applinks: App clips target app: applinks: and appclips: Archived and uploaded build to App Store Connect. Green "Testing" status via Testflight. On Distribution tab, green "Valid" status for build domain. Advanced App Clip Experience green "Received" status. Developer App Clip Testing Diagnostics: Green "Register Advanced Experience" status Green "App Clip Code" status Warning "App Clip Published on App Store" Orange Circle "Associated Domains" After looking at countless threads, I still cannot for the life of me find a solution to test the App Clip. Any guidance would be extremely appreciated. I had also submitted a support ticket with case ID #102552504973.
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479
Apr ’25
SwiftData with shared and private containers
I was hoping for an update of SwiftData which adopted the use of shared and public CloudKit containers, in the same way it does for the private CloudKit container. So firstly, a big request to any Apple devs reading, for this to be a thing! Secondly, what would be a sensible way of adding a shared container in CloudKit to an existing app that is already using SwiftData? Would it be possible to use the new DataStore method to manage CloudKit syncing with a public or shared container?
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3.6k
Feb ’25
self.window.isVisible = NO not working in windowDidLoad
The following code won't work: - (void)windowDidLoad { [super windowDidLoad]; self.window.isVisible = NO; } The only main window still shows on application startup (in a minimal newly created app). One of my published apps in App Store relies on this behavior which had been working for many years since I started Xcode development.
Topic: UI Frameworks SubTopic: AppKit
11
0
159
Apr ’25
Changing the live activity without push notification
I am trying to implement "Live activity" to my app. I am following the Apple docs. Link: https://developer.apple.com/documentation/activitykit/displaying-live-data-with-live-activities Example code: struct LockScreenLiveActivityView: View { let context: ActivityViewContext<PizzaDeliveryAttributes> var body: some View { VStack { Spacer() Text("\(context.state.driverName) is on their way with your pizza!") Spacer() HStack { Spacer() Label { Text("\(context.attributes.numberOfPizzas) Pizzas") } icon: { Image(systemName: "bag") .foregroundColor(.indigo) } .font(.title2) Spacer() Label { Text(timerInterval: context.state.deliveryTimer, countsDown: true) .multilineTextAlignment(.center) .frame(width: 50) .monospacedDigit() } icon: { Image(systemName: "timer") .foregroundColor(.indigo) } .font(.title2) Spacer() } Spacer() } .activitySystemActionForegroundColor(.indigo) .activityBackgroundTint(.cyan) } } Actually, the code is pretty straightforward. We can use the timerInterval for count-down animation. But when the timer ends, I want to update the Live Activity view. If the user re-opens the app, I can update it, but what happens if the user doesn't open the app? Is there a way to update the live activity without using push notifications?
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6.3k
Mar ’25
@Observable and didSet?
I'm in the process of migrating to the Observation framework but it seems like it is not compatible with didSet. I cannot find information about if this is just not supported or a new approach needs to be implemented? import Observation @Observable class MySettings { var windowSize: CGSize = .zero var isInFullscreen = false var scalingMode: ScalingMode = .scaled { didSet { ... } } ... } This code triggers this error: Instance member 'scalingMode' cannot be used on type 'MySettings'; did you mean to use a value of this type instead? Anyone knows what needs to be done? Thanks!
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3
4.6k
Jan ’25
UISlider valueChanged has uninitialized UIEvent
This issue was in the first iOS 26 beta and it still there with Xcode 26 beta 6 (17A5305f). Feedback is FB18581605 and contains sample project to reproduce the issue. I assign a target and action to a UISlider for the UIControl.Event.valueChanged value: addTarget(self, action: #selector(sliderValueDidChange), for: .valueChanged) Here’s the function. @objc func sliderValueDidChange(_ sender: UISlider, event: UIEvent) { print(event) } When printing the event value, there is a crash. When checking the event value with lldb, it appears uninitialized.
Topic: UI Frameworks SubTopic: UIKit Tags:
11
6
910
Oct ’25
Cell Delegate Method Not Being Called
I have set up a collection view cell programmatically which I am registering in the cell registration of a diffable data source. I have set up a delegate for the cell, and the view controller which contains the collection view as the delegate for the cell. However, calling the cell delegate method from the cell is not calling the method in the view controller. This is my code: `// in my view controller: cell.delegate = self // in my collection view cell: delegate?.repromptLLMForIconName(iconName, index: index, emotion: emotion, red: red, green: green, blue: blue) ` But although the delegate method in the collection view gets called, my method implementation in the view controller does not. What could possibly be going wrong?
Topic: UI Frameworks SubTopic: UIKit
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0
153
Jul ’25
Sheet presentationDetents breaks after rapid open/dismiss cycles
Basic Information Please provide a descriptive title for your feedback: Sheet presentationDetents breaks after rapid open/dismiss cycles Which platform is most relevant for your report? iOS Description Steps to Reproduce: Create a sheet with presentationDetents([.medium]) Rapidly perform these actions multiple times (usually 3-4 times): a. Open the sheet b. Immediately scroll down to dismiss Open the sheet again Observe that the sheet now appears at .large size, ignoring the .medium detent Expected Result: Sheet should consistently maintain .medium size regardless of how quickly it is opened and dismissed. Actual Result: After rapid open/dismiss cycles, the sheet ignores .medium detent and appears at .large size. Reproduction Rate: Occurs consistently after 3-4 rapid open/dismiss cycles More likely to occur with faster open/dismiss actions Configuration: iOS 18 Xcode 16.0 (16A242d) SwiftUI Device: iPhone 14
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1.2k
Mar ’25
Is there a tech note for menuBuilder?
I'm trying to piece together how I should reason about multiple windows, activating menus and items. For instance, I have an email command. If a document is open, it emails just that document. If the collection view holding that document is open, it generates an attachment representing the collection. (this happens with buttons right now but this really feels like a menu item) How do I tell which window is active (document/collection) in order to have the right menu item available. If the user is adding a document I don't want the "new" command open, I only want one editing view. I saw sample code to include or remove commands but not disable them. I feel like there's a whole conceptual layer I want to understand with the interplay with scenes but don't know where to look for documentation. I searched here but there's hardly any threads on this. TIA
Topic: UI Frameworks SubTopic: UIKit
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218
Oct ’25
Crash when assigning NSImage to `@objc dynamic var` property
Xcode downloaded a crash report for my app which I don't quite understand. It seems the following line caused the crash: myEntity.image = newImage where myEntity is of type MyEntity: class MyEntity: NSObject, Identifiable { @objc dynamic var image: NSImage! ... } The code is called on the main thread. According to the crash report, thread 0 makes that assignment, and at the same time thread 16 is calling [NSImageView asynchronousPreparation:prepareResultUsingParameters:]. What could cause such a crash? Could I be doing something wrong or is this a bug in macOS? crash.crash
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202
Aug ’25