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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iOS 14.3 UITextField leak?
Why is the UIKeyboard implementation still holding a reference to this UITextField, thus keeping it from being deallocated? The memory debugger shows: UIKeyboardImpl -> UIKBAutofillController -> NSMutableDictionary -> NSMutable...(Storage) -> UITextField Any idea what's going on there?
Topic: UI Frameworks SubTopic: UIKit Tags:
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2.6k
2w
iPadOS 26 - Status bar overlaps with navigation bar
Hello, I'm experiencing a navigation bar positioning issue with my UIKit iPad app on iPadOS 26 (23A340) using Xcode 26 (17A321). The navigation bar positions under the status bar initially, and after orientation changes to landscape, it positions incorrectly below its expected location. This occurs on both real device (iPad mini A17 Pro) and simulator. My app uses UIKit + Storyboard with a Root Navigation Controller. A stack overflow post has reproduce the bug event if it's not in the same configuration: https://stackoverflow.com/questions/79752945/xcode-26-beta-6-ipados-26-statusbar-overlaps-with-navigationbar-after-presen I have checked all safe areas and tried changing some constraints, but nothing works. Have you encountered this bug before, or do you need additional information to investigate this issue?
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571
Nov ’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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Oct ’25
Live caller id lookup
We are trying to implement live caller id lookup, there is lack of documentation and we would like to understand few blockers that we have: Based on this documentation page: https://developer.apple.com/documentation/identitylookup/setting-up-the-http-endpoints-for-live-caller-id-lookup: What exactly should accept/return these endpoints?. There is no detailed description of the response/request schema for any endpoint. What are the usage scenarios of the "/key" method? If it is possible to get a more detailed explanation regarding Evaluation Key usage as it is not clear from the available documentation. Based on this step by step implementation description: https://github.com/apple/live-caller-id-lookup-example/blob/main/Sources/PIRService/PIRService.docc/Authentication.md: The 6th step: "Authentication server returns the list of public keys (potentially through a proxy)". What is the endpoint path and response format expected by the iOS system? This step refers to calling the '/config' endpoint ? The 8th step: "Authentication server verifies the User Token and returns the public key that is associated with the User Tier. ..." What is the the endpoint path and request/response format expected by the iOS system? The 9th step: "The system constructs a Privacy Pass token request using the specific public key. The token request is sent along with the User Token to the authentication server". What is the request/response format expected by the iOS system? The 11th step: "When a PIR request is made, the system attached an unused Privacy Pass token to the request. The PIR node can use the public key to verify that the token is valid and that assures that the request is authorized". What is the request/response format expected by the iOS system? On executing refreshPIRParameters fom app I get this error: LiveCallerIDLookupManager.shared.refreshPIRParameters(forExtensionWithIdentifier: LiveCallerIdExtensionName) Unable to query status due to errors: server error (Access DeniedAccess DeniedYou don't have permission to access "http://www.example.com/config" on this server.Reference #18.cdde00d4.1738074526.3a38870https://errors.edgesuite.net/18.cdde00d4.1738074526.3a38870) Why it tries to reach example.com/config but not our serviceURL or tokenIssuerURL? Any help would be appreciated.
Topic: UI Frameworks SubTopic: General
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Jan ’25
App Clips don't work
We're building a UGC AR app and are leveraging App Clips to distribute AR experiences without app download. Since earlier this week, many of our users are reporting sharing experiences as App Clip doesn't work anymore. They are getting the message "AppClip unavailable" on a little card. We attached a QR code to try it yourself and a link to a different experience. We tried with multiple experiences and on multiple devices already. https://scenery.app/experience/1C925FDE-E49A-489B-BA14-58A4E532E645 Interestingly, we can't pinpoint the issue to an exact device or OS. We tested on many devices and on most, the AppClip is being displayed as unavailable, stating "App Clip unavailable", whereas it works on a few. It all worked fine last week (before September 12th). iPhone 13 Pro Max, iOS26: works iPhone SE, iOS 17: works iPhone 16 Pro, iOS 26: doesn't work iPhone 12 Pro Max, iOS 26: doesn't work iPhone 12 mini, iOS 18: does not work iPad 9th gen, iOS 26: doesn't work Please help. Our users are very dissatisfied as they expect this to work and it's a crucial feature. We already filed a radar via Feedback assistant: FB20303890
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Oct ’25
String catalogs in packages
We have separated much of our UI into different packages to reduce complexity and compile time. When we recently tested using new .xcstrings string catalogs, we hit an unexpected problem. Strings extracted from SwiftUI components like Text or Button are extracted into the Localizable.xcstrings in the same package, but the default behaviour of Text(_ key:tableName:bundle:comment:) is to use Bundle.main. When the default behaviour of the string extraction isn't to extract to the main app target, this introduces a very fragile system where it's easy to add code that looks localised, but ends up failing lookup at runtime. I don't feel comfortable that we will always remember to define the correct module every time we create a Text. Also, other components like Button doesn't have an init that takes a Bundle, so we would also have to remember that Button(_ titleKey:action:) can now only be used in a package if we make sure that the main bundle contains a matching key. Is there a way for us to make sure that strings are always extracted to the same place as they are resolved against by default? Either by having strings in packages extracted to an xcstrings file in the main app or having Text default to resolving against the module bundle by default?
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2.3k
Jun ’25
CIContext sporadically crashes on macOS 15.4/15.5, iOS 18.4/18.5
We have some rather old code that worked for many years, but recently started to crash sporadically here: The crash looks like this: or Our code is called from many threads concurrently, but as said it worked without any issues until recently. I've found the apparently same crash on iOS at this Reddit post: https://www.reddit.com/r/iOSProgramming/comments/1kle4h4/ios_185_doesnt_fix_cicontext_rendering_crash/ Recap: we believe it started on macOS 18.4 and is still on macOS 18.5. But maybe it was already on macOS 18.3. This matches the observation in the Reddit post well. Should we create a feedback with sysdiagnose? Thanks! :)
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Jun ’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
SwiftUI Slider will cause app to crash on macOS Tahoe RC
Hello, creating a simple-as-it-gets Slider in SwiftUI and then running that app on Mac Catalyst with the macOS idiom enabled, the app crashes: struct ContentView: View { @State private var sliderValue: Double = 0.4 var body: some View { VStack { Slider(value: $sliderValue) } .padding() } } running this will result in an exception: _setMinimumEnabledValue: is not supported on UISlider when running Catalyst apps in the Mac idiom. See UIBehavioralStyle for possible alternatives. This is obviously not ideal and also apparently no documented. Is there a workaround for this? It used to work for on macOS Sonoma. macOS 26 RC Xcode 26 RC FB20191635 Thanks!
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357
Oct ’25
Button taps in scroll views are not cancelled on scroll inside sheets
When you touch down on a button in a scroll view, you can cancel the tap by scrolling. In SwiftUI, this works correctly when the scroll view is not inside a dismissible sheet. However, if the scroll view is inside a sheet that can be dismissed with a drag gesture, scrolling does not cancel the button touch, and after scrolling, the button tap is activated. This happens whether the modal is presented from SwiftUI using the sheet modifier, or wrapped in a UIHostingController and presented from UIKit. This is a huge usability issue for modals with scrollable content that have buttons inside of them. Video of behavior: https://youtube.com/shorts/w6eqsmTrYiU Easily reproducible with this code: import SwiftUI struct ContentView: View { @State private var isPresentingSheet = false var body: some View { ScrollView { LazyVStack { ForEach(0..<100, id: \.self) { index in Button { isPresentingSheet = true } label: { Text("Button \(index)") .padding(.horizontal) .padding(.vertical, 5) .frame(maxWidth: .infinity, alignment: .leading) } } } .padding() } .sheet(isPresented: $isPresentingSheet) { ContentView() } } }
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1.8k
Feb ’25
App Clip links encoded as a QR Code do not load when scanned on an iPhone camera
Using an App Clip link encoded into a QR Code shows an error when scanning the encoded QR Code on an iPhone or iPad. After being scanned, the App Clip's banner is visible, but a message says: "App Clip Unavailable". Accessing the same App Clip URL via Safari works as expected. I've filed a feedback with more details and screenshots of the issue here: FB17891015 Thanks!
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Jun ’25
Exception unarchiving UIToolbar in iOS 18.5 simulator with Xcode 26 beta 2
I'm running into a persistent problem with the iOS 18.5 simulator in Xcode 26 beta 2. I have built a very simple test app with a storyboard that includes only a toolbar added to the ViewController scene in the storyboard. The test app runs fine in iOS 26 simulators.When I try to run it in the iOS 18.5 simulator for iPhone Pro or iPad (16), it fails while unarchiving the storyboard (as far as I can tell) with this error message in the Xcode console: *** Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason: 'Could not instantiate class named TtGC5UIKit17UICoreHostingViewVCS_21ToolbarVisualProvider8RootView because no class named TtGC5UIKit17UICoreHostingViewVCS_21ToolbarVisualProvider8RootView was found; the class needs to be defined in source code or linked in from a library (ensure the class is part of the correct target)' terminating due to uncaught exception of type NSException CoreSimulator 1043 - Device: iPad (A16) (3E70E25F-8434-4541-960D-1B58EB4037F3) - Runtime: iOS 18.5 (22F77) - DeviceType: iPad (A16) I'd love a simple workaround for this.
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Aug ’25
SIGTRAP crash in CoreGraphics font rendering pipeline (iOS 18.4)
We're observing new crashes specifically on iOS 18.4 devices with this pattern: Exception Type: SIGTRAP Exception Codes: fault addr: 0x000000019bc0f088 Crashed Thread: 0 Thread 0 0 libsystem_malloc.dylib _xzm_xzone_malloc_from_tiny_chunk.cold.1 + 36 1 libsystem_malloc.dylib __xzm_xzone_malloc_from_tiny_chunk + 612 2 libsystem_malloc.dylib __xzm_xzone_find_and_malloc_from_tiny_chunk + 112 3 libsystem_malloc.dylib __xzm_xzone_malloc_tiny_outlined + 312 4 CoreGraphics CG::Path::Path(CG::Path const&) + 132 5 CoreGraphics _CGPathCreateMutableCopyByTransformingPath + 112 6 CoreGraphics _CGFontCreateGlyphPath + 144 7 CoreGraphics _CGGlyphBuilderLockBitmaps + 1112 8 CoreGraphics _render_glyphs + 292 9 CoreGraphics _draw_glyph_bitmaps + 1116 10 CoreGraphics _ripc_DrawGlyphs + 1464 11 CoreGraphics CG::DisplayList::executeEntries(std::__1::__wrap_iter<std::__1::shared_ptr<CG::DisplayListEntry const>*>, std::__1::__wrap_iter<std::__1::shared_ptr<CG::DisplayListEntry const>*>, CGContextDelegate*, CGRenderingState*, CGGStack*, CGRect const*, __CFDictionary const*, bool) + 1328 12 CoreGraphics _CGDisplayListDrawInContextDelegate + 340 13 QuartzCore _CABackingStoreUpdate_ + 612 14 QuartzCore ____ZN2CA5Layer8display_Ev_block_invoke + 120 15 QuartzCore -[CALayer _display] + 1512 16 QuartzCore CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 420 17 QuartzCore CA::Context::commit_transaction(CA::Transaction*, double, double*) + 476 18 QuartzCore CA::Transaction::commit() + 644 19 UIKitCore ___34-[UIApplication _firstCommitBlock]_block_invoke_2 + 36 20 CoreFoundation ___CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 28 21 CoreFoundation ___CFRunLoopDoBlocks + 352 22 CoreFoundation ___CFRunLoopRun + 868 23 CoreFoundation _CFRunLoopRunSpecific + 572 24 GraphicsServices _GSEventRunModal + 168 25 UIKitCore -[UIApplication _run] + 816 26 UIKitCore _UIApplicationMain + 336 27 app _main + 132 28 dyld __dyld_process_info_create + 33284 Key Observations: Crash occurs during font glyph path creation (CGFontCreateGlyphPath) Involves memory allocation in malloc's xzone implementation 100% reproducible on iOS 18.4, not seen in prior OS versions Occurs during standard CALayer rendering operations Not tied to any specific font family or glyph content Questions for Apple: Is this crash signature recognized as a known issue in iOS 18.4's CoreGraphics? Could changes to xzone memory management in iOS 18.4 interact poorly with font rendering? Are there specific conditions that might trigger SIGTRAP in CGPathCreateMutableCopyByTransformingPath? Any recommended mitigations for text rendering while awaiting system updates?
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628
May ’25
iOS 18.4 Beta: On iPhones which support Dynamic Island, the AppDelegate method applicationDidBecomeActive() takes longer to be called.
When testing with iOS 18.4 Beta on iPhones which support Dynamic Island, after doing a Face ID authentication, the amount of time it takes before the AppDelegate method applicationDidBecomeActive() is called takes longer than iPhones that do not support Dynamic Island. The time it takes is about double, 1.2 seconds vs 2.5 seconds on average. This does not occur with versions before 18.4 Beta. Anyone else seeing this?
Topic: UI Frameworks SubTopic: UIKit
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348
May ’25
My app doesn't respond on iPhone Air iOS 26.1.
My app doesn't respond on iPhone Air iOS 26.1. After startup, my app shows the main view with a tab bar controller containing 4 navigation controllers. However, when a second-level view controller is pushed onto any navigation controller, the UI freezes and becomes unresponsive. The iPhone simulator running iOS 26.1 exhibits the same problem. The debug profile shows CPU usage at 100%. However, other devices and simulators do not have this problem.
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5d
Small Size Icons and NSToolbar on MacOS 12.0 Monterey -- can it work?
I noticing that Monterey defaults to the NSWindowToolbarStyleAutomatic / NSWindowToolbarStyleUnified toolbar style, which suppresses the "use Small Size" menu item and customization checkbox. So I've set the window to use NSWindowToolbarStyleExpanded. However, the toolbar will no longer change to a smaller icon size, as it did in MacOS 10.14, 10.15, and 11.0. I've tried to set the toolbar item sizing to "Automatic" for all of our toolbar icons, but that results in bad positioning in both Regular and Small Size mode -- the height is way too big. The native size of the icon .png files are 128 x 128. What's odd is that if I resize the window with the toolbar to be wider, the NSToolbarItems in the overflow area will be displayed in the toolbar are 128 x 128, where the rest of the toolbar icons get displayed as a 32 x 32 icon. The only way to get it to layout remotely correct is to make the NSToolbarItem to have an explicit minimum size of 24 x 24 and maximum size of 32 x 32. And that USED to allow "small size", but on Monterey, it no longer does. Anyone had any success with small size icons on Monterey?
Topic: UI Frameworks SubTopic: AppKit Tags:
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1.2k
Sep ’25
tabViewBottomAccessory in 26.1: View's @State is lost when switching tabs
Any view that is content for the tabViewBottomAccessory API fails to retain its state as of the last couple of 26.1 betas (and RC). The loss of state happens (at least) when the currently selected tab is switched (filed as FB20901325). Here's code to reproduce the issue: struct ContentView: View { @State private var selectedTab = TabSelection.one enum TabSelection: Hashable { case one, two } var body: some View { TabView(selection: $selectedTab) { Tab("One", systemImage: "1.circle", value: .one) { BugExplanationView() } Tab("Two", systemImage: "2.circle", value: .two) { BugExplanationView() } } .tabViewBottomAccessory { AccessoryView() } } } struct AccessoryView: View { @State private var counter = 0 // This guy's state gets lost (as of iOS 26.1) var body: some View { Stepper("Counter: \(counter)", value: $counter) .padding(.horizontal) } } struct BugExplanationView: View { var body: some View { ScrollView { VStack(alignment: .leading, spacing: 16) { Text("(1) Manipulate the counter state") Text("(2) Then switch tabs") Text("BUG: The counter state gets unexpectedly reset!") } .multilineTextAlignment(.leading) } } }
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iOS 26 Liquid Glass not showing
I’m not seeing Liquid Glass on any standard components. A month ago around July 17th I ran our app and saw Liquid Glass on our tab view and various standard components. Those components have not been changed and yet I’m no longer seeing Liquid Glass in our app at all. Components that were previously liquid glass but now are not include TabView and back navigation buttons. I set the UIDesignRequiresCompatibility key explicitly to false but no luck. I was seeing this in Beta 7 and Beta 8 on a real device and on a sim.
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288
Oct ’25