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How do you support Preferred Font Size / Dynamic Type on macOS?
On macOS 26, how do you support the Preferred Text Size value as defined in the Accessibility Settings? Historically, "Dynamic Type" has not been available on macOS. However, the user has some control over text size through the Accessibility Settings. On macOS 26, a small subset of applications are honouring changes to that value include Finder, Mail, and sidebars in many applications. Dynamic sizing in table views has been available on macOS for awhile. But Mail.app, in particular, is also adjusting the font sizes used in the message's body pane while the Finder is adjusting font sizes used for Desktop icons. I can't find an NSNotification that is fired when the user adjusts the Accessibility Text Size slider, nor can I find an API to read the current value. NSFont.preferredFont(forTextStyle:options:) looks promising but the fonts returned do not appear to take the user's Accessibility setting into account. (Nor do they update dynamically.) SwiftUI's Text("Apple").font(.body) performs similarly to NSFont in that it does respect the style, but it does not honour dynamic sizing. NSFontDescriptor has a bunch of interesting methods, but none that seem to apply to Accessibility Text Size. Given an AppKit label: let label = NSTextField(labelWithString: "AppKit") label.font = NSFont.preferredFont(forTextStyle: .body) Or a SwiftUI label: Text("SwiftUI").font(.body) How do I make either of them responsive to the user's Text Size setting under Accessibility? Note this is on macOS 26 / Xcode 26. I realize there have been some previous forum posts related to this issue but hoping that things might have improved since then.
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Button in ToolbarItem is not completely tapable on iOS 26
I have an icon button in toolbar but only the icon is triggering tap events while outside icon button gives tap feedback but event is not firing. Code: ToolbarItem(placement: .navigationBarTrailing) { Button(action: toggleBookmark) { Image(systemName: isBookmarked ? "bookmark.fill" : "bookmark") .resizable() .aspectRatio(0.8, contentMode: .fit) .frame(width: 20, height: 20) } } Here toggleBookmark function is only called if I click on Image but not if I click outside image but on the circular button that appears on iOS 26. See this screen recording.
Topic: UI Frameworks SubTopic: SwiftUI
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UI Testing for iPadOS 26 Menu Bar items
I need to validate whether specific menu items are correctly enabled/disabled. The XCUIAutomation elements for my menu items do not appear in the tree shown by displaying the XCUIApplication object in the debugger when building and testing the iPadOS version of my application. When running the application in an iPad simulator, I can make the menu bar appear by swiping down. The testing works as expected for the MacOS build and test. I did try to use the recording feature, but was not successful in creating a series of commands that worked for a test run.
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Performance degradation and redraw loops when syncing SwiftUI Charts with custom AxisMarks
I am reporting a reproducible performance issue in iOS 18.6 where synchronizing the scroll position of two Chart views via chartScrollPosition(id:) causes a complete redraw loop when custom AxisMarks are used. This occurs even when the axis marks are technically "hidden," leading to significant frame drops and stuttering on modern hardware like the iPhone 15. Environment Device: iPhone 15 OS: iOS 18.6 (22G86) Frameworks: SwiftUI, Swift Charts, Observation The Issue When using a shared @Observable state to sync two charts, the scrolling is fluid only if the axes are at their default settings. As soon as a custom AxisMarks block is added to either chart, the following behavior is observed: Diffing Failure: The framework appears unable to maintain the identity of the axis components during the scroll update. Redraw Loop: Instead of an incremental scroll translation, the diffing algorithm triggers a full reload/re-render of both charts on every scroll offset change. Impact: CPU spikes to 100% and the UI becomes unresponsive. This happens even if the custom AxisMarks is used solely to hide the axis (e.g., AxisMarks { _ in }), suggesting the issue is with the custom declaration itself rather than the complexity of the marks being rendered. Steps to Reproduce Create two Chart views in a VStack. Bind both to a single @Observable property using .chartScrollPosition(id: $state.pos). Add any .chartXAxis { AxisMarks(...) { ... } } modifier. Scroll either chart; observe the stuttering. import SwiftUI import Charts import Observation @Observable class ChartState { var scrollPos: Date = .now } struct PerformanceBugView: View { @State private var state = ChartState() var body: some View { VStack { Chart(data) { ... } .chartScrollPosition(id: $state.scrollPos) .chartXAxis { // This custom mark triggers the performance issue AxisMarks { _ in AxisValueLabel() } } Chart(data) { ... } .chartScrollPosition(id: $state.scrollPos) } } } Questions for the Community/Apple Engineers: Is there a way to provide a stable identifier to AxisMarks to prevent them from being treated as "new" during a scroll update? Why does even an empty AxisMarks block (used for hiding) trigger a layout invalidation that standard axes do not? Are there internal optimizations for chartScrollPosition that are bypassed when the axis layout is customized?
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TabView with .page style vibrates and reloads content during sheet detent drag
FeedBack Id: FB22031397 (Demo proj Attached to Feedback) Description: When a TabView using .page tabViewStyle is placed inside a sheet configured with multiple presentationDetents, dragging the sheet handle to resize between detents causes the TabView to re-render all its pages on every frame of the drag gesture. This results in visible content vibration, scroll position jumping, and tab content flashing during the drag. The issue is fully reproducible with the attached minimal demo project. Steps to Reproduce: Run the attached TabViewSheetVibrationDemo.swift on any iOS device or simulator Tap "Open Sheet" on the main screen Swipe left to any tab Scroll down inside the tab so content is not at the top Grab the sheet drag indicator at the top and slowly drag upward or downward to resize between medium and large detent Observe the tab content while dragging Expected Results: The TabView page content should remain completely stable during sheet resize. Scroll positions should be preserved and no re-rendering should occur because the underlying data has not changed. The sheet should resize smoothly while tab content stays still. Actual Results: The TabView re-renders all pages on every frame of the drag gesture. This causes: Visible content vibration and jitter while dragging the sheet handle Scroll position jumping back toward the top mid-drag Tab content flashing as pages are recreated The problem is proportional to drag speed — slower drags show a stuttering effect, faster drags cause a full content flash Configuration: All Xcode including beta iOS 26 (also reproduced on iOS 16, iOS 17 and iOS 18) Reproducible on both Simulator and real device Affects iPhone and iPad
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Wrong appearance of decimalPad keyboard in dark mode
Hi. The following code causes UI mismatch on iOS26. Keyboard with type decimalPad and appearance as dark is displayed as popUp with wrong colors. Before iOS26 keyboard was regular with correct color scheme. Please advice either how to make the scheme correct or force to display regular keyboard instead of popup. class ViewController: UIViewController { @IBOutlet weak var textField: UITextField! override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view. textField.keyboardType = .decimalPad textField.keyboardAppearance = .dark view.backgroundColor = .darkGray } }
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Crown Sequencer warning on Scroll
I have a Form (scrollable) that contains 2 inputs as a Picker and a Stepper where frequency is an enum and time an Int. struct ConfigurationView: View { @Bindable var configuration: ConfigurationModel var body: some View { NavigationStack { Form { Picker(.frequency, selection: $configuration.frequency) { /* ... */ } Stepper(value: $configuration.time, in: 1...8) { // Stepper Label } .focusable() Button(.save) { configuration.save() } .buttonStyle(.borderedProminent) .listRowBackground(Color.clear) } .navigationTitle(.configuration) } } } The main issue I'm facing is a delay in the UI (1-3 seconds) while interacting with the Digital Crown over the focused Stepper which prints a Crown Sequencer warning: Crown Sequencer was set up without a view property. This will inevitably lead to incorrect crown indicator states This mainly happens when the Picker, which is showed as a modal or Sheet, changes its value, so the Stepper no longer gets focusable again. Looking into the docs, lectures and WWDC videos I just found that we need to provide a some sort of a focus, that's why the Stepper control has a focusable() modifier. I don't know if there is an overlap between the scroll and the focus event on the control.
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Increase Contrast reduces List selection contrast in dark appearance in SwiftUI NavigationSplitView
[Submitted as FB22200608] With Increase Contrast turned on, the selected row highlight in a List behaves inconsistently between light and dark appearance on iPad. In light appearance the blue selection highlight correctly becomes darker, but in dark appearance it becomes lighter instead. The text contrast ratio drops from about 3:1 to about 1.5:1, well below accessibility guidelines. This reproduces both in the simulator and on a physical device. The sample uses a standard SwiftUI List inside NavigationSplitView with built-in selection styling. No custom colors or styling are applied. REPRO STEPS Create a new Multiplatform project. Replace ContentView with code below. Build and run on iPad. Select an item in the list. Turn on Dark appearance (Cmd-Shift-A in Simulator). Turn on Increase Contrast (Cmd-Control-Shift-A in Simulator). Observe the selected row highlight. ACTUAL In light appearance, the blue selection highlight becomes darker when Increase Contrast is on, improving contrast as expected. In dark appearance, the blue selection highlight becomes lighter when Increase Contrast is on, reducing contrast between the selection background and the white text. EXPECTED Increase Contrast should consistently increase contrast. In dark appearance, the selection highlight should become darker—or otherwise increase contrast with the foreground text—not lighter. SAMPLE CODE struct ContentView: View { @State private var selection: String? var body: some View { NavigationSplitView { Text("Sidebar") } content: { List(selection: $selection) { Text("Item One") .tag("One") Text("Item Two") .tag("Two") } } detail: { if let selection { Text(selection) } else { Text("Select an item") } } } } SCREEN RECORDING CONTACTS The Contacts app behaves correctly. When Increase Contrast is turned on, the selection blue becomes darker, improving contrast. PASSWORDS The Passwords app, however, exhibits the issue. With Increase Contrast turned on, the selection blue becomes lighter instead of darker, reducing contrast.
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.contactAccessPicker shows blank sheet on iOS 26.1
I’m running into an issue using .contactAccessPicker on a device running iOS 26.1 - a blank sheet appears instead of the expected Contact Access Picker. It works on: Simulator (iOS 26.0) Device + Simulator (iOS 18.6) The issue appears specific to real devices on iOS 26.0+. Environment: Device: iPhone 16 Pro iOS Versions Tested: 26.0 and 26.1 Xcode 26.0.1 SwiftUI app, deployment target: iOS 17+ @available(iOS 18.0, *) private var contactPicker: some View { contactsSettingsButton("Title") { showContactPicker = true } .contactAccessPicker(isPresented: $showContactPicker) { _ in Task { await contactManager.fetchContacts() showSelectContacts = true } } } Filed a Feedback: FB20929400 Is there a known workaround?
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CarPlay: CPListImageRowItem images and CPNowPlayingTemplate buttons occasionally not displaying (requires device reboot)
Device: iPhone 17 Pro Max iOS version: iOS 26.3 CarPlay type: Wired We are encountering two intermittent UI issues in CarPlay when running our music application. The problems occur occasionally and cannot be recovered without restarting the device. Issue 1: CPListImageRowItem image not displaying On the CarPlay home page, some images occasionally fail to appear. Implementation details: The list is updated using CPListTemplate.updateSections. Each item is a CPListImageRowItem. On iOS versions below 26, images are updated using updateImages. On iOS 26, images are provided through CPListImageRowItem.elements, where each element is a CPListImageRowItemRowElement. Observed behavior: Logs confirm that the data is correctly provided. However, in failing cases the CPListImageRowItemRowElement appears with both title and subtitle equal to nil. The image is not rendered in the UI even though the item exists. Issue 2: Now Playing bottom buttons occasionally missing On the Now Playing screen, the bottom control buttons sometimes fail to appear. Implementation details: Buttons are updated using CPNowPlayingTemplate.updateNowPlayingButtons. The buttons are instances of CPNowPlayingImageButton. Observed behavior: Occasionally the buttons are not displayed. Once this occurs, the UI does not recover. Restarting the phone immediately resolves the issue. Additional observations The issue appears to occur intermittently. Once triggered, it persists until the device is rebooted. Similar behavior has been observed in other music apps (for example, QQ Music). Questions Are there known CarPlay UI rendering issues related to CPListImageRowItem or CPNowPlayingTemplate in recent iOS versions? Is there any recommended workaround or lifecycle handling that might prevent these UI elements from failing to render? Any guidance would be greatly appreciated.
Topic: UI Frameworks SubTopic: UIKit Tags:
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ShareLink "save Image" action dismiss parent view
ShareLink works fine except for save image action which dismiss the presenting view first time system shows the premission alert so image get saved without any problem but for the next saves image get saved then share sheet dismiss and also presenting view dismiss as well here is a sample code ` internal import System import UniformTypeIdentifiers import SwiftUI struct RootView: View { @State private var isPresented: Bool = false var body: some View { ZStack { Color.white Button("Show parent view") { isPresented = true } } .sheet(isPresented: $isPresented) { ParentView() } } } struct ParentView: View { @State private var isPresented: Bool = false var body: some View { NavigationStack { ZStack { Color.red.opacity(0.5) } .toolbar { ToolbarItem() { let name = "\(UUID().uuidString)" let image = UIImage(named: "after")! return ShareLink( item: ShareableImage(image: image, fileName: name), preview: SharePreview( name, image: Image(uiImage: image) ) ) { Image(uiImage: UIImage(resource: .Icons.share24)) .resizable() .foregroundStyle(Color.black) .frame(width: 24, height: 24) } } } } } } struct ShareableImage: Transferable { let image: UIImage let fileName: String static var transferRepresentation: some TransferRepresentation { FileRepresentation(exportedContentType: .png) { item in let fileURL = FileManager.default.temporaryDirectory .appendingPathComponent(item.fileName) .appendingPathExtension("png") guard let data = item.image.pngData() else { throw NSError(domain: "ImageEncodingError", code: 0) } try data.write(to: fileURL) return SentTransferredFile(fileURL) } } } `
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Gesture & SimultaneousGesture interfere with ScrollView behaviour.
I have faced a problem while I was trying to implement a reorder drag & drop view. I found that when I add any kind of .gesture or .simultaneousGesture, a ScrollView's scrolling behavior wasn't working properly (does not scroll at all). ScrollView(.vertical, showsIndicators: false) { ForEach($items) { $item in EditorCard(stepDetails: item) .simultaneousGesture( customCombinedGesture(item) ) } } This ScrollView worked fine with .onLongPressGesture(), however, I wanted to use custom gestures sequences.
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macOS 26: NSTokenField crashes due to NSGenericException caused by too many Update Constraints
This example application crashes when entering any text to the token field with FAULT: NSGenericException: The window has been marked as needing another Update Constraints in Window pass, but it has already had more Update Constraints in Window passes than there are views in the window. The app uses controlTextDidChange to update a live preview where it accesses the objectValue of the token field. If one character is entered, it also looks like the NSTokenFieldDelegate methods tokenField(_:styleForRepresentedObject:) tokenField(_:editingStringForRepresentedObject:) tokenField(_:representedObjectForEditing:) are called more than 10000 times until the example app crashes on macOS Tahoe 26 beta 6. I've reported this issue with beta 1 as FB18088608, but haven't heard back so far. I have multiple occurrences of this issue in my app, which is working fine on previous versions of macOS. I haven't found a workaround yet, and I’m getting anxious of this issue persisting into the official release.
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Cross-domain issue in wkwebview
Subject: Cross-Domain Access Behaviour in WKWebView – Clarification Required Description: We are facing a cross-domain issue in our iOS application where WKWebView loads content from one domain and attempts to access resources/data from another domain. Current Setup: App Platform: iOS WebView: WKWebView iOS Version: 26 Primary Domain: *.franconnectqa.net Data/Analytics Domain: analytics.franconnectdev.net SSL: Valid certificates configured ATS: Enabled Issue: When WKWebView loads content from franconnectqa.net, it attempts to access resources or analytics from analytics.franconnectdev.net, resulting in cross-domain restrictions. We would like to understand: Does WKWebView support cross-domain resource access by default? Are there any configuration settings that allow controlled cross-domain access? Are there known limitations regarding cookies, local storage, or session sharing across domains? Does WKWebView enforce additional restrictions beyond standard browser CORS policies? Are there recommended best practices for handling cross-domain scenarios in WKWebView? Expected Behavior: We want to determine whether: Cross-domain access is supported under certain configurations, OR The recommended approach is to align all resources under the same domain. Kindly provide guidance on the supported architecture and any configuration recommendations.
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Is there a way in AppKit to apply the Liquid Glass soft edge effect to a view placed outside an NSScrollView?
I’m developing a text editor that provides a line number view. This view is placed next to the NSScrollView that contains the main text view, rather than inside the scroll view. The line number view updates its drawing in sync with the NSScrollView’s scrolling and text editing in the NSTextView, so it can display the correct line numbers. This approach worked fine through macOS 15, but on macOS 26 with Liquid Glass, the line numbers end up being drawn without the expected blur/soft edge effect under the window toolbar area. In AppKit, some view controllers provide APIs to switch edge effects between soft/hard, but I can’t find any API to control this for the window toolbar region. I considered simply not drawing the numbers outside the content area, but if possible I’d like to apply the Tahoe-style soft edge effect instead. Does anyone have ideas? Is this currently impossible, meaning the only option is to file a feedback/API request? Also, for various reasons, the traditional approach of implementing line numbers by subclassing NSRulerView is difficult for my app.
Topic: UI Frameworks SubTopic: AppKit
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iOS 26: default gray background on UITabBarItem
In iOS 26, when a UITabBarItem is selected, a gray background appears behind the selected item. This seems to happen automatically with the new tab bar design. I tried configuring the tab bar using UITabBarAppearance, but the background highlight still appears. Is this the expected behavior in iOS 26 or is there a recommended way to configure the tab bar so that only the icon and title change color when selected?
Topic: UI Frameworks SubTopic: UIKit
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Crash in SwiftUICore SDFStyle.distanceRange.getter
I've been receiving crash reports about a crash in SDFStyle.distanceRange.getter. I haven't been able to reproduce this, and users haven't given me much information about the circumstances or can't reliably reproduce this either. Googling didn't give any results. I'm happy for any pointers in the right direction. All reports have been on iOS 26 so far. 2026-03-02_23-35-03.7381_+0800-93830d0f537cfb381b42a7e9812953d772adfe64.crash
Topic: UI Frameworks SubTopic: SwiftUI
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TextKit 2 + SwiftUI (NSViewRepresentable): NSTextLayoutManager rendering attributes don’t reliably draw/update
I’m embedding an NSTextView (TextKit 2) inside a SwiftUI app using NSViewRepresentable. I’m trying to highlight dynamic subranges (changing as the user types) by providing per-range rendering attributes via NSTextLayoutManager’s rendering-attributes mechanism. The issue: the highlight is unreliable. Often, the highlight doesn’t appear at all even though the delegate/data source is returning attributes for the expected range. Sometimes it appears once, but then it stops updating even when the underlying “highlight range” changes. This feels related to SwiftUI - AppKit layout issue when using NSViewRepresentable (as said in https://developer.apple.com/documentation/swiftui/nsviewrepresentable). What I’ve tried Updating the state that drives the highlight range and invalidating layout fragments / asking for relayout Ensuring all updates happen on the main thread. Calling setNeedsDisplay(_:) on the NSViewRepresentable’s underlying view. Toggling the SwiftUI view identity (e.g. .id(...)) to force reconstruction (works, but too expensive / loses state). Question In a SwiftUI + NSViewRepresentable setup with TextKit 2, what is the correct way to make NSTextLayoutManager re-query and redraw rendering attributes when my highlight ranges change? Is there a recommended invalidation call for TextKit 2 to trigger re-rendering of rendering attributes? Or is this a known limitation when hosting NSTextView inside SwiftUI, where rendering attributes aren’t reliably invalidated? If this approach is fragile, is there a better pattern for dynamic highlights that avoids mutating the attributed string (to prevent layout/scroll jitter)?
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Switching to custom keyboard size glitches
I've created a custom keyboard and implemented the: class KeyboardViewController: UIInputViewController The imlementation looks like this: override func viewDidLoad() { super.viewDidLoad() var stack = UIStackView() stack.axis = .vertical stack.spacing = 8 stack.translatesAutoresizingMaskIntoConstraints = false stack.distribution = .fill stack.heightAnchor.constraint(equalToConstant: 200).isActive = true .... view.addSubview(stack) NSLayoutConstraint.activate([ stack.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20), stack.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20), stack.topAnchor.constraint(equalTo: view.topAnchor, constant: 10), stack.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -10) ]) The problem is that the keyboard seems to start showing in the size (I've printed the parent frame): Optional(<UIView: 0x101008480; frame = (0 0; 390 844); autoresize = W+H; layer = <CALayer: 0x600000207b80>>) and than resizes to my given height. But it's not fast enough so that I can see some glitches whenever I switch from another keyboard to my custom keyboard. Is there a way to prevent this resizing or start the keyboard in a given size? This is just not the best user experience.
Topic: UI Frameworks SubTopic: UIKit
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How do you support Preferred Font Size / Dynamic Type on macOS?
On macOS 26, how do you support the Preferred Text Size value as defined in the Accessibility Settings? Historically, "Dynamic Type" has not been available on macOS. However, the user has some control over text size through the Accessibility Settings. On macOS 26, a small subset of applications are honouring changes to that value include Finder, Mail, and sidebars in many applications. Dynamic sizing in table views has been available on macOS for awhile. But Mail.app, in particular, is also adjusting the font sizes used in the message's body pane while the Finder is adjusting font sizes used for Desktop icons. I can't find an NSNotification that is fired when the user adjusts the Accessibility Text Size slider, nor can I find an API to read the current value. NSFont.preferredFont(forTextStyle:options:) looks promising but the fonts returned do not appear to take the user's Accessibility setting into account. (Nor do they update dynamically.) SwiftUI's Text("Apple").font(.body) performs similarly to NSFont in that it does respect the style, but it does not honour dynamic sizing. NSFontDescriptor has a bunch of interesting methods, but none that seem to apply to Accessibility Text Size. Given an AppKit label: let label = NSTextField(labelWithString: "AppKit") label.font = NSFont.preferredFont(forTextStyle: .body) Or a SwiftUI label: Text("SwiftUI").font(.body) How do I make either of them responsive to the user's Text Size setting under Accessibility? Note this is on macOS 26 / Xcode 26. I realize there have been some previous forum posts related to this issue but hoping that things might have improved since then.
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Button in ToolbarItem is not completely tapable on iOS 26
I have an icon button in toolbar but only the icon is triggering tap events while outside icon button gives tap feedback but event is not firing. Code: ToolbarItem(placement: .navigationBarTrailing) { Button(action: toggleBookmark) { Image(systemName: isBookmarked ? "bookmark.fill" : "bookmark") .resizable() .aspectRatio(0.8, contentMode: .fit) .frame(width: 20, height: 20) } } Here toggleBookmark function is only called if I click on Image but not if I click outside image but on the circular button that appears on iOS 26. See this screen recording.
Topic: UI Frameworks SubTopic: SwiftUI
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Partially disable liquid glass effect from navigation bars but retain on tabbar
I want to be able to disable all liquid glass effects from my Navigation bar, and it's bar buttons. But I still want to be able to have the liquid glass effect on my UITabbar. Is there a way to disable glass effects from navbar and still retain them all for tabbars using UIKit?
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UI Testing for iPadOS 26 Menu Bar items
I need to validate whether specific menu items are correctly enabled/disabled. The XCUIAutomation elements for my menu items do not appear in the tree shown by displaying the XCUIApplication object in the debugger when building and testing the iPadOS version of my application. When running the application in an iPad simulator, I can make the menu bar appear by swiping down. The testing works as expected for the MacOS build and test. I did try to use the recording feature, but was not successful in creating a series of commands that worked for a test run.
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Performance degradation and redraw loops when syncing SwiftUI Charts with custom AxisMarks
I am reporting a reproducible performance issue in iOS 18.6 where synchronizing the scroll position of two Chart views via chartScrollPosition(id:) causes a complete redraw loop when custom AxisMarks are used. This occurs even when the axis marks are technically "hidden," leading to significant frame drops and stuttering on modern hardware like the iPhone 15. Environment Device: iPhone 15 OS: iOS 18.6 (22G86) Frameworks: SwiftUI, Swift Charts, Observation The Issue When using a shared @Observable state to sync two charts, the scrolling is fluid only if the axes are at their default settings. As soon as a custom AxisMarks block is added to either chart, the following behavior is observed: Diffing Failure: The framework appears unable to maintain the identity of the axis components during the scroll update. Redraw Loop: Instead of an incremental scroll translation, the diffing algorithm triggers a full reload/re-render of both charts on every scroll offset change. Impact: CPU spikes to 100% and the UI becomes unresponsive. This happens even if the custom AxisMarks is used solely to hide the axis (e.g., AxisMarks { _ in }), suggesting the issue is with the custom declaration itself rather than the complexity of the marks being rendered. Steps to Reproduce Create two Chart views in a VStack. Bind both to a single @Observable property using .chartScrollPosition(id: $state.pos). Add any .chartXAxis { AxisMarks(...) { ... } } modifier. Scroll either chart; observe the stuttering. import SwiftUI import Charts import Observation @Observable class ChartState { var scrollPos: Date = .now } struct PerformanceBugView: View { @State private var state = ChartState() var body: some View { VStack { Chart(data) { ... } .chartScrollPosition(id: $state.scrollPos) .chartXAxis { // This custom mark triggers the performance issue AxisMarks { _ in AxisValueLabel() } } Chart(data) { ... } .chartScrollPosition(id: $state.scrollPos) } } } Questions for the Community/Apple Engineers: Is there a way to provide a stable identifier to AxisMarks to prevent them from being treated as "new" during a scroll update? Why does even an empty AxisMarks block (used for hiding) trigger a layout invalidation that standard axes do not? Are there internal optimizations for chartScrollPosition that are bypassed when the axis layout is customized?
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TabView with .page style vibrates and reloads content during sheet detent drag
FeedBack Id: FB22031397 (Demo proj Attached to Feedback) Description: When a TabView using .page tabViewStyle is placed inside a sheet configured with multiple presentationDetents, dragging the sheet handle to resize between detents causes the TabView to re-render all its pages on every frame of the drag gesture. This results in visible content vibration, scroll position jumping, and tab content flashing during the drag. The issue is fully reproducible with the attached minimal demo project. Steps to Reproduce: Run the attached TabViewSheetVibrationDemo.swift on any iOS device or simulator Tap "Open Sheet" on the main screen Swipe left to any tab Scroll down inside the tab so content is not at the top Grab the sheet drag indicator at the top and slowly drag upward or downward to resize between medium and large detent Observe the tab content while dragging Expected Results: The TabView page content should remain completely stable during sheet resize. Scroll positions should be preserved and no re-rendering should occur because the underlying data has not changed. The sheet should resize smoothly while tab content stays still. Actual Results: The TabView re-renders all pages on every frame of the drag gesture. This causes: Visible content vibration and jitter while dragging the sheet handle Scroll position jumping back toward the top mid-drag Tab content flashing as pages are recreated The problem is proportional to drag speed — slower drags show a stuttering effect, faster drags cause a full content flash Configuration: All Xcode including beta iOS 26 (also reproduced on iOS 16, iOS 17 and iOS 18) Reproducible on both Simulator and real device Affects iPhone and iPad
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Wrong appearance of decimalPad keyboard in dark mode
Hi. The following code causes UI mismatch on iOS26. Keyboard with type decimalPad and appearance as dark is displayed as popUp with wrong colors. Before iOS26 keyboard was regular with correct color scheme. Please advice either how to make the scheme correct or force to display regular keyboard instead of popup. class ViewController: UIViewController { @IBOutlet weak var textField: UITextField! override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view. textField.keyboardType = .decimalPad textField.keyboardAppearance = .dark view.backgroundColor = .darkGray } }
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Crown Sequencer warning on Scroll
I have a Form (scrollable) that contains 2 inputs as a Picker and a Stepper where frequency is an enum and time an Int. struct ConfigurationView: View { @Bindable var configuration: ConfigurationModel var body: some View { NavigationStack { Form { Picker(.frequency, selection: $configuration.frequency) { /* ... */ } Stepper(value: $configuration.time, in: 1...8) { // Stepper Label } .focusable() Button(.save) { configuration.save() } .buttonStyle(.borderedProminent) .listRowBackground(Color.clear) } .navigationTitle(.configuration) } } } The main issue I'm facing is a delay in the UI (1-3 seconds) while interacting with the Digital Crown over the focused Stepper which prints a Crown Sequencer warning: Crown Sequencer was set up without a view property. This will inevitably lead to incorrect crown indicator states This mainly happens when the Picker, which is showed as a modal or Sheet, changes its value, so the Stepper no longer gets focusable again. Looking into the docs, lectures and WWDC videos I just found that we need to provide a some sort of a focus, that's why the Stepper control has a focusable() modifier. I don't know if there is an overlap between the scroll and the focus event on the control.
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Increase Contrast reduces List selection contrast in dark appearance in SwiftUI NavigationSplitView
[Submitted as FB22200608] With Increase Contrast turned on, the selected row highlight in a List behaves inconsistently between light and dark appearance on iPad. In light appearance the blue selection highlight correctly becomes darker, but in dark appearance it becomes lighter instead. The text contrast ratio drops from about 3:1 to about 1.5:1, well below accessibility guidelines. This reproduces both in the simulator and on a physical device. The sample uses a standard SwiftUI List inside NavigationSplitView with built-in selection styling. No custom colors or styling are applied. REPRO STEPS Create a new Multiplatform project. Replace ContentView with code below. Build and run on iPad. Select an item in the list. Turn on Dark appearance (Cmd-Shift-A in Simulator). Turn on Increase Contrast (Cmd-Control-Shift-A in Simulator). Observe the selected row highlight. ACTUAL In light appearance, the blue selection highlight becomes darker when Increase Contrast is on, improving contrast as expected. In dark appearance, the blue selection highlight becomes lighter when Increase Contrast is on, reducing contrast between the selection background and the white text. EXPECTED Increase Contrast should consistently increase contrast. In dark appearance, the selection highlight should become darker—or otherwise increase contrast with the foreground text—not lighter. SAMPLE CODE struct ContentView: View { @State private var selection: String? var body: some View { NavigationSplitView { Text("Sidebar") } content: { List(selection: $selection) { Text("Item One") .tag("One") Text("Item Two") .tag("Two") } } detail: { if let selection { Text(selection) } else { Text("Select an item") } } } } SCREEN RECORDING CONTACTS The Contacts app behaves correctly. When Increase Contrast is turned on, the selection blue becomes darker, improving contrast. PASSWORDS The Passwords app, however, exhibits the issue. With Increase Contrast turned on, the selection blue becomes lighter instead of darker, reducing contrast.
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259
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.contactAccessPicker shows blank sheet on iOS 26.1
I’m running into an issue using .contactAccessPicker on a device running iOS 26.1 - a blank sheet appears instead of the expected Contact Access Picker. It works on: Simulator (iOS 26.0) Device + Simulator (iOS 18.6) The issue appears specific to real devices on iOS 26.0+. Environment: Device: iPhone 16 Pro iOS Versions Tested: 26.0 and 26.1 Xcode 26.0.1 SwiftUI app, deployment target: iOS 17+ @available(iOS 18.0, *) private var contactPicker: some View { contactsSettingsButton("Title") { showContactPicker = true } .contactAccessPicker(isPresented: $showContactPicker) { _ in Task { await contactManager.fetchContacts() showSelectContacts = true } } } Filed a Feedback: FB20929400 Is there a known workaround?
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322
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CarPlay: CPListImageRowItem images and CPNowPlayingTemplate buttons occasionally not displaying (requires device reboot)
Device: iPhone 17 Pro Max iOS version: iOS 26.3 CarPlay type: Wired We are encountering two intermittent UI issues in CarPlay when running our music application. The problems occur occasionally and cannot be recovered without restarting the device. Issue 1: CPListImageRowItem image not displaying On the CarPlay home page, some images occasionally fail to appear. Implementation details: The list is updated using CPListTemplate.updateSections. Each item is a CPListImageRowItem. On iOS versions below 26, images are updated using updateImages. On iOS 26, images are provided through CPListImageRowItem.elements, where each element is a CPListImageRowItemRowElement. Observed behavior: Logs confirm that the data is correctly provided. However, in failing cases the CPListImageRowItemRowElement appears with both title and subtitle equal to nil. The image is not rendered in the UI even though the item exists. Issue 2: Now Playing bottom buttons occasionally missing On the Now Playing screen, the bottom control buttons sometimes fail to appear. Implementation details: Buttons are updated using CPNowPlayingTemplate.updateNowPlayingButtons. The buttons are instances of CPNowPlayingImageButton. Observed behavior: Occasionally the buttons are not displayed. Once this occurs, the UI does not recover. Restarting the phone immediately resolves the issue. Additional observations The issue appears to occur intermittently. Once triggered, it persists until the device is rebooted. Similar behavior has been observed in other music apps (for example, QQ Music). Questions Are there known CarPlay UI rendering issues related to CPListImageRowItem or CPNowPlayingTemplate in recent iOS versions? Is there any recommended workaround or lifecycle handling that might prevent these UI elements from failing to render? Any guidance would be greatly appreciated.
Topic: UI Frameworks SubTopic: UIKit Tags:
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ShareLink "save Image" action dismiss parent view
ShareLink works fine except for save image action which dismiss the presenting view first time system shows the premission alert so image get saved without any problem but for the next saves image get saved then share sheet dismiss and also presenting view dismiss as well here is a sample code ` internal import System import UniformTypeIdentifiers import SwiftUI struct RootView: View { @State private var isPresented: Bool = false var body: some View { ZStack { Color.white Button("Show parent view") { isPresented = true } } .sheet(isPresented: $isPresented) { ParentView() } } } struct ParentView: View { @State private var isPresented: Bool = false var body: some View { NavigationStack { ZStack { Color.red.opacity(0.5) } .toolbar { ToolbarItem() { let name = "\(UUID().uuidString)" let image = UIImage(named: "after")! return ShareLink( item: ShareableImage(image: image, fileName: name), preview: SharePreview( name, image: Image(uiImage: image) ) ) { Image(uiImage: UIImage(resource: .Icons.share24)) .resizable() .foregroundStyle(Color.black) .frame(width: 24, height: 24) } } } } } } struct ShareableImage: Transferable { let image: UIImage let fileName: String static var transferRepresentation: some TransferRepresentation { FileRepresentation(exportedContentType: .png) { item in let fileURL = FileManager.default.temporaryDirectory .appendingPathComponent(item.fileName) .appendingPathExtension("png") guard let data = item.image.pngData() else { throw NSError(domain: "ImageEncodingError", code: 0) } try data.write(to: fileURL) return SentTransferredFile(fileURL) } } } `
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Gesture & SimultaneousGesture interfere with ScrollView behaviour.
I have faced a problem while I was trying to implement a reorder drag & drop view. I found that when I add any kind of .gesture or .simultaneousGesture, a ScrollView's scrolling behavior wasn't working properly (does not scroll at all). ScrollView(.vertical, showsIndicators: false) { ForEach($items) { $item in EditorCard(stepDetails: item) .simultaneousGesture( customCombinedGesture(item) ) } } This ScrollView worked fine with .onLongPressGesture(), however, I wanted to use custom gestures sequences.
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macOS 26: NSTokenField crashes due to NSGenericException caused by too many Update Constraints
This example application crashes when entering any text to the token field with FAULT: NSGenericException: The window has been marked as needing another Update Constraints in Window pass, but it has already had more Update Constraints in Window passes than there are views in the window. The app uses controlTextDidChange to update a live preview where it accesses the objectValue of the token field. If one character is entered, it also looks like the NSTokenFieldDelegate methods tokenField(_:styleForRepresentedObject:) tokenField(_:editingStringForRepresentedObject:) tokenField(_:representedObjectForEditing:) are called more than 10000 times until the example app crashes on macOS Tahoe 26 beta 6. I've reported this issue with beta 1 as FB18088608, but haven't heard back so far. I have multiple occurrences of this issue in my app, which is working fine on previous versions of macOS. I haven't found a workaround yet, and I’m getting anxious of this issue persisting into the official release.
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313
Activity
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Cross-domain issue in wkwebview
Subject: Cross-Domain Access Behaviour in WKWebView – Clarification Required Description: We are facing a cross-domain issue in our iOS application where WKWebView loads content from one domain and attempts to access resources/data from another domain. Current Setup: App Platform: iOS WebView: WKWebView iOS Version: 26 Primary Domain: *.franconnectqa.net Data/Analytics Domain: analytics.franconnectdev.net SSL: Valid certificates configured ATS: Enabled Issue: When WKWebView loads content from franconnectqa.net, it attempts to access resources or analytics from analytics.franconnectdev.net, resulting in cross-domain restrictions. We would like to understand: Does WKWebView support cross-domain resource access by default? Are there any configuration settings that allow controlled cross-domain access? Are there known limitations regarding cookies, local storage, or session sharing across domains? Does WKWebView enforce additional restrictions beyond standard browser CORS policies? Are there recommended best practices for handling cross-domain scenarios in WKWebView? Expected Behavior: We want to determine whether: Cross-domain access is supported under certain configurations, OR The recommended approach is to align all resources under the same domain. Kindly provide guidance on the supported architecture and any configuration recommendations.
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Is there a way in AppKit to apply the Liquid Glass soft edge effect to a view placed outside an NSScrollView?
I’m developing a text editor that provides a line number view. This view is placed next to the NSScrollView that contains the main text view, rather than inside the scroll view. The line number view updates its drawing in sync with the NSScrollView’s scrolling and text editing in the NSTextView, so it can display the correct line numbers. This approach worked fine through macOS 15, but on macOS 26 with Liquid Glass, the line numbers end up being drawn without the expected blur/soft edge effect under the window toolbar area. In AppKit, some view controllers provide APIs to switch edge effects between soft/hard, but I can’t find any API to control this for the window toolbar region. I considered simply not drawing the numbers outside the content area, but if possible I’d like to apply the Tahoe-style soft edge effect instead. Does anyone have ideas? Is this currently impossible, meaning the only option is to file a feedback/API request? Also, for various reasons, the traditional approach of implementing line numbers by subclassing NSRulerView is difficult for my app.
Topic: UI Frameworks SubTopic: AppKit
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iOS 26: default gray background on UITabBarItem
In iOS 26, when a UITabBarItem is selected, a gray background appears behind the selected item. This seems to happen automatically with the new tab bar design. I tried configuring the tab bar using UITabBarAppearance, but the background highlight still appears. Is this the expected behavior in iOS 26 or is there a recommended way to configure the tab bar so that only the icon and title change color when selected?
Topic: UI Frameworks SubTopic: UIKit
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301
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Crash in SwiftUICore SDFStyle.distanceRange.getter
I've been receiving crash reports about a crash in SDFStyle.distanceRange.getter. I haven't been able to reproduce this, and users haven't given me much information about the circumstances or can't reliably reproduce this either. Googling didn't give any results. I'm happy for any pointers in the right direction. All reports have been on iOS 26 so far. 2026-03-02_23-35-03.7381_+0800-93830d0f537cfb381b42a7e9812953d772adfe64.crash
Topic: UI Frameworks SubTopic: SwiftUI
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292
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TextKit 2 + SwiftUI (NSViewRepresentable): NSTextLayoutManager rendering attributes don’t reliably draw/update
I’m embedding an NSTextView (TextKit 2) inside a SwiftUI app using NSViewRepresentable. I’m trying to highlight dynamic subranges (changing as the user types) by providing per-range rendering attributes via NSTextLayoutManager’s rendering-attributes mechanism. The issue: the highlight is unreliable. Often, the highlight doesn’t appear at all even though the delegate/data source is returning attributes for the expected range. Sometimes it appears once, but then it stops updating even when the underlying “highlight range” changes. This feels related to SwiftUI - AppKit layout issue when using NSViewRepresentable (as said in https://developer.apple.com/documentation/swiftui/nsviewrepresentable). What I’ve tried Updating the state that drives the highlight range and invalidating layout fragments / asking for relayout Ensuring all updates happen on the main thread. Calling setNeedsDisplay(_:) on the NSViewRepresentable’s underlying view. Toggling the SwiftUI view identity (e.g. .id(...)) to force reconstruction (works, but too expensive / loses state). Question In a SwiftUI + NSViewRepresentable setup with TextKit 2, what is the correct way to make NSTextLayoutManager re-query and redraw rendering attributes when my highlight ranges change? Is there a recommended invalidation call for TextKit 2 to trigger re-rendering of rendering attributes? Or is this a known limitation when hosting NSTextView inside SwiftUI, where rendering attributes aren’t reliably invalidated? If this approach is fragile, is there a better pattern for dynamic highlights that avoids mutating the attributed string (to prevent layout/scroll jitter)?
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Switching to custom keyboard size glitches
I've created a custom keyboard and implemented the: class KeyboardViewController: UIInputViewController The imlementation looks like this: override func viewDidLoad() { super.viewDidLoad() var stack = UIStackView() stack.axis = .vertical stack.spacing = 8 stack.translatesAutoresizingMaskIntoConstraints = false stack.distribution = .fill stack.heightAnchor.constraint(equalToConstant: 200).isActive = true .... view.addSubview(stack) NSLayoutConstraint.activate([ stack.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20), stack.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20), stack.topAnchor.constraint(equalTo: view.topAnchor, constant: 10), stack.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -10) ]) The problem is that the keyboard seems to start showing in the size (I've printed the parent frame): Optional(<UIView: 0x101008480; frame = (0 0; 390 844); autoresize = W+H; layer = <CALayer: 0x600000207b80>>) and than resizes to my given height. But it's not fast enough so that I can see some glitches whenever I switch from another keyboard to my custom keyboard. Is there a way to prevent this resizing or start the keyboard in a given size? This is just not the best user experience.
Topic: UI Frameworks SubTopic: UIKit
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