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iOS 18 hit testing functionality differs from iOS 17
I created a Radar for this FB14766095, but thought I would add it here for extra visibility, or if anyone else had any thoughts on the issue. Basic Information Please provide a descriptive title for your feedback: iOS 18 hit testing functionality differs from iOS 17 What type of feedback are you reporting? Incorrect/Unexpected Behavior Description: Please describe the issue and what steps we can take to reproduce it: We have an issue in iOS 18 Beta 6 where hit testing functionality differs from the expected functionality in iOS 17.5.1 and previous versions of iOS. iOS 17: When a sheet is presented, the hit-testing logic considers subviews of the root view, meaning the rootView itself is rarely the hit view. iOS 18: When a sheet is presented, the hit-testing logic changes, sometimes considering the rootView itself as the hit view. Code: import SwiftUI struct ContentView: View { @State var isPresentingView: Bool = false var body: some View { VStack { Text("View One") Button { isPresentingView.toggle() } label: { Text("Present View Two") } } .padding() .sheet(isPresented: $isPresentingView) { ContentViewTwo() } } } #Preview { ContentView() } struct ContentViewTwo: View { @State var isPresentingView: Bool = false var body: some View { VStack { Text("View Two") } .padding() } } extension UIWindow { public override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? { /// Get view from superclass. guard let hitView = super.hitTest(point, with: event) else { return nil } print("RPTEST rootViewController = ", rootViewController.hashValue) print("RPTEST rootViewController?.view = ", rootViewController?.view.hashValue) print("RPTEST hitView = ", hitView.hashValue) if let rootView = rootViewController?.view { print("RPTEST rootViewController's view memory address: \(Unmanaged.passUnretained(rootView).toOpaque())") print("RPTEST hitView memory address: \(Unmanaged.passUnretained(hitView).toOpaque())") print("RPTEST Are they equal? \(rootView == hitView)") } /// If the returned view is the `UIHostingController`'s view, ignore. print("MTEST: hitTest rootViewController?.view == hitView", rootViewController?.view == hitView) print("MTEST: -") return hitView } } Looking at the print statements from the provided sample project:
 iOS 17 presenting a sheet from a button tap on the ContentView(): RPTEST rootViewController's view memory address: 0x0000000120009200 RPTEST hitView memory address: 0x000000011fd25000 RPTEST Are they equal? false MTEST: hitTest rootViewController?.view == hitView false RPTEST rootViewController's view memory address: 0x0000000120009200 RPTEST hitView memory address: 0x000000011fd25000 RPTEST Are they equal? false MTEST: hitTest rootViewController?.view == hitView false iOS 17 dismiss from presented view: RPTEST rootViewController's view memory address: 0x0000000120009200 RPTEST hitView memory address: 0x000000011fe04080 RPTEST Are they equal? false MTEST: hitTest rootViewController?.view == hitView false RPTEST rootViewController's view memory address: 0x0000000120009200 RPTEST hitView memory address: 0x000000011fe04080 RPTEST Are they equal? false MTEST: hitTest rootViewController?.view == hitView false iOS 18 presenting a sheet from a button tap on the ContentView(): RPTEST rootViewController's view memory address: 0x000000010333e3c0 RPTEST hitView memory address: 0x0000000103342080 RPTEST Are they equal? false MTEST: hitTest rootViewController?.view == hitView false RPTEST rootViewController's view memory address: 0x000000010333e3c0 RPTEST hitView memory address: 0x000000010333e3c0 RPTEST Are they equal? true MTEST: hitTest rootViewController?.view == hitView true You can see here ☝️ that in iOS 18 the views have the same memory address on the second call and are evaluated to be the same. This differs from iOS 17. iOS 18 dismiss RPTEST rootViewController's view memory address: 0x000000010333e3c0 RPTEST hitView memory address: 0x0000000103e80000 RPTEST Are they equal? false MTEST: hitTest rootViewController?.view == hitView false RPTEST rootViewController's view memory address: 0x000000010333e3c0 RPTEST hitView memory address: 0x0000000103e80000 RPTEST Are they equal? false MTEST: hitTest rootViewController?.view == hitView false The question I want to ask: Is this an intended change, meaning the current functionality in iOS 18 is expected? Or is this a bug and it's something that needs to be fixed? As a user, I would expect that the hit testing functionality would remain the same from iOS 17 to iOS 18. Thank you for your time.
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4.5k
Aug ’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:
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1.1k
4d
Widget link broken by `.desaturated` image rendering mode
Using desaturated mode on an image in a widget will break any links or buttons that use the image as their 'label'. Using the following will just open the app as if there was no link at all - therefore just using the fallback userActivity handler, or any .widgetURL() urls provided. Link(destination: URL(string: "bug://never-works")!) { Image("puppy") .widgetAccentedRenderingMode(.desaturated) } The same goes for buttons: Button(intent: MyDemoIntent()) { Image("puppy") .widgetAccentedRenderingMode(.desaturated) } I've tried hacky solutions like putting the link behind the image using a ZStack, and disabling hit testing on the image, but they don't work. Anything else to try? Logged as Feedback #15152620.
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2w
Xcode 26 - Crashing Loading Custom TabBarViewController
When I build my app for iPad OS, either 26, or 18.5, as well as iOS on 16.5 from Xcode 26 with UIDesignRequiresCompatibility enabled my app is crashing as it loads the main UIViewController, a subclassed UITabBarController which is being loaded programatically from a Storyboard from another SplashScreen ViewController. On i(Pad)OS 18.5 I get this error: Thread 1: "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)" On iPadOS 26 I get this error: UIKitCore/UICoreHostingView.swift:54: Fatal error: init(coder:) has not been implemented There is no issue building from Xcode 16.4, regardless of targeted i(Pad)OS.
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1.2k
Aug ’25
iOS 26 Beta bug - keyboard toolbar with bottom safe area inset
Hello! I have experienced a weird bug in iOS 26 Beta (8) and previous beta versions. The safe area inset is not correctly aligned with the keyboard toolbar on real devices and simulators. When you focus a new textfield the bottom safe area is correctly placed aligned the keyboard toolbar. On real devices the safe area inset view is covered slightly by the keyboard toolbar, which is even worse than on the simulator. Here's a clip from a simulator: Here's the code that reproduced the bug I experienced in our app. #Preview { NavigationStack { ScrollView { TextField("", text: .constant("")) .padding() .background(Color.secondary) TextField("", text: .constant("")) .padding() .background(Color.green) } .padding() .safeAreaInset(edge: .bottom, content: { Color.red .frame(maxWidth: .infinity) .frame(height: 40) }) .toolbar { ToolbarItem(placement: .keyboard) { Button {} label: { Text("test") } } } } }
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Sep ’25
SwiftUI ScrollView performance in macOS 15
There seems to be a performance issue when scrolling using the track pad with SwiftUI scroll views in macOS 15. This issue is NOT present in macOS 14. When using the track pad the scrolling is not smooth, but "stutters". However scrolling using the scroll bars is very smooth. The "stuttering" is worse if the SwiftUI ScrollView is in the detail view of a NavigationSplitView. The problem is not noticeable in scroll views with a small number views, but when the more views inside the scroll view, the more prominent the problem becomes. I have a simple example app that illustrates the problem here (the example app is a simplification of my app Yammixer): https://github.com/danwaltin/SwiftUIScrollViewPerformance When running this example app on macOS 14 (Sonoma) on an Intel i7 Mac book pro from 2019 the scrolling is "buttery smooth". But on macOS 15 (Sequoia) on my Apple Silicon M1 Mac book pro the issue is very obvious. When using Instruments I see that on macOS 15 "flame graph" shows that 85% of the execution time is in a "_hitTestForEvent" method. If the test app does not use NavigationSplitView about 70% of execution time is in the _hitTestForEvent method.
Topic: UI Frameworks SubTopic: SwiftUI
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2.4k
Feb ’25
interactive glassEffect bug?
Applying glass effect, providing a shape isn't resulting in the provided shape rendering the interaction correctly. .glassEffect(.regular.tint(Color(event.calendar.cgColor)).interactive(), in: .rect(cornerRadius: 20)) results in properly drawn view but interactive part of it is off. light and shimmer appear as a capsule within the rect.
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Jun ’25
Xcode 15 Breaks Usage Of TextField.focused()
My usage of TextField.focused() works fine in Xcode 14.3.1 but is broken as of Xcode 15. I first noticed it in the second beta and it's still broken as of the 4th beta. Feedback / OpenRadar # FB12432084 import SwiftUI struct ContentView: View { @State private var text = "" @FocusState var isFocused: Bool var body: some View { ScrollView { TextField("Test", text: $text) .textFieldStyle(.roundedBorder) .focused($isFocused) Text("Text Field Is Focused: \(isFocused.description)") } } }
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1.6k
Feb ’25
Keep ScrollView position when adding items on the top
I am using a LayzVStack embedded into a ScrollView. The list items are fetched from a core data store by using a @FetchResult or I tested it also with the new @Query command coming with SwiftData. The list has one hundred items 1, 2, 3, ..., 100. The user scrolled the ScrollView so that items 50, 51, ... 60 are visible on screen. Now new data will be fetched from the server and updates the CoreData or SwiftData model. When I add new items to the end of the list (e.g 101, 102, 103, ...) then the ScrollView is keeping its position. Opposite to this when I add new items to the top (0, -1, -2, -3, ...) then the ScrollView scrolls down. Is there a way with the new SwiftData and SwiftUI ScrollView modifiers to update my list model without scrolling like with UIKit where you can query and set the scroll offset pixel wise?
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9.7k
May ’25
Combining NavigationSplitView and TabView in iOS 18
Hi folks, I've used a NavigationSplitView within one of the tabs of my app since iOS 16, but with the new styling in iOS 18 the toolbar region looks odd. In other tabs using e.g. simple stacks, the toolbar buttons are horizontally in line with the new tab picker, but with NavigationSplitView, the toolbar leaves a lot of empty space at the top (see below). Is there anything I can do to adjust this, or alternatively, continue to use the old style? Thanks!
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2.8k
Oct ’25
[macOS Sequoia] Using RegisterEventHotkey with option and shift modifiers doesn't working anymore
Hello. In my app, I use RegisterEventHotkey to implement global keyboard shortcuts to trigger actions. Up until macOS Sequoia, I was able to use a keyboard shortcut with option and shift as the modifiers, like option shift 2 (⌥ ⇧ 2). Now, on macOS Sequoia, using RegisterEventHotkey to register a hotkey with those exact modifiers (option and shift), regardless of the key, fails with the error -9868 (eventInternalErr). Is this a documented and wanted change, or is this a bug? Other modifier keys (just command, command option, command shift, command control, control shift, etc), all work. Any insight into this would be appreciated. (Feedback filed: FB15163561) Thank you, Matthias
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Nov ’25
LazyVGrid (embedded in a List) does not resize automatically when content increases and layout changes
I have a List in a sidebar style which contains a LazyVGrid and a Section with a simple list contents. Every thing works well except when content increases and layout changes (from two columns to one column) for the LazyVGrid with editMode changing to .active ... LazyVGrid does not expand/resize when the content increases (the increased content gets clipped)...but does when user expands/folds on the section below :(. However LazyVGrid resizes to show the entire content when the content shrinks with editMode reverting to .inactive Note: If I replace the List with a ScrollView...lazyVGrid resizes perfectly when content increases in editMode = .active....but then I would lose all the Sidebar and List characteristics for the Section below :( Also, looks like .onMove is not supported in LazyVGrids Any pointers to solve the LazyVGrid (embedded in a List) not resizing or expanding when content increases ... will be deeply appreciated. var body: some View {         List {             LazyVGrid(columns: editMode?.wrappedValue == .active ? singleColumn : twoColumns, alignment: .leading, spacing: 10) {                 ForEach(editMode?.wrappedValue == .active ? allDashItems : selectedDashItems) { dashitem in                     DashItemCell(dashitem)                                         }                 .onMove(perform: moveDashItem)                 .environment(\.editMode, editMode)             }             Section(header: Text("Bottom Section")) {                     ForEach (sectionList)	{ item in                         ListItemCell(item)                     }                     .onDelete(perform: deleteFolder)                     .onMove(perform: moveFolder)                 }         }         .listStyle(SidebarListStyle()) }
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1.7k
May ’25
Navigation broken in iOS 18.4
All of a sudden, after iOS 18.4 was released, I am having tons of navigation problems in my app in production. Buttons navigating to empty pages, views seeming to 'freeze', top navigation bar mismatched with the content of the page. It seems that iOS 18.4 broke a critical piece of UIKit + SwiftUI bridging functionality that my project relies on. My application is written with both UIKit and SwiftUI components. Here is a breakdown of my setup: UIApplicationDelegate > UIWindow > rootViewController of window is a UITabBarController > each tab is a UINavigationController rootViewController of nav controller is a UIHostingController > rootView of the hosting controller is a SwiftUI View In my SwiftUI views, I have been using NavigationLink for horizontal 'push' style navigation in my SwiftUI views. I do not use NavigationView, I only rely on the bridging capabilities of UINavigationController to action on my NavigationLinks. This has never been an issue, until iOS 18.4 was released. Now, when running iOS 18.4, I am having all sorts of unexpected behavior in the UI. I will break down 2 of these use cases here: Use case A: In one of my SwiftUI views, I have a ForEach for which each element's view is a NavigationLink. This is using the NavigationLink(_ destination:,label:) initializer. Navigating forward from here works/looks normal. However, once I try to navigate backward from that destination (tap the 'Back' button in top left), the view goes blank and the navigation bar at the top of the page (which is maintained by the UINavigationController instance) does not change. If I call popToRootViewController on that nav controller, the navigation bar at the top of the page returns to its normal state, but the view is still blank. It is not until after I have called popToRootViewController, and then navigate to a different tab of the UITabBarController and return to the initial tab, does the SwiftuI content view (the one with the ForEach) finally redraw and the view hierarchy is restored. Here is a warning that is logged in the console when I tap the 'Back ' button: Top view controller's view unexpectedly not in window for navigation transition. Skipping layout. nav = <UINavigationController: 0x1110bbe00>, topVC = <TtGC7SwiftUI19UIHostingControllerV5MyApp10MyPage: 0x106814e00> EDIT: If I replace the NavigationLink with a call to UINavigationController.pushViewController, I am still seeing the exact same behavior. Pressing back button makes the view empty > need to pop to root view controller and switch tabs in order to restore the view. Use case B Another instance of this issue happens whenever I try to use a NavigationLink inside of a view that itself was the destination of a NavigationLink in its parent view (i.e.: Root view > detail view > sub-detail view). For example, take the detail view destination in use case A. I have tapped a NavigationLink from the ForEach and landed on the detail view. Again, so far things work/look normal. Now, if I tap on another NavigationLink from that detail view, the view does not transition to the new page. The top navigation bar does transition, and shows the title and actions associated with this second destination. However, the view of this second destination is not displayed. It is worth noting that the same warning I mentioned above is also logged when I tap the NavigationLink to navigate to this second destination. Top view controller's view unexpectedly not in window for navigation transition. Skipping layout. nav = <UINavigationController: 0x109859400>, topVC = <TtGC7SwiftUI19UIHostingControllerVVS_19BridgedPresentation8RootView: 0x300ab8000> Strangely, if I switch to a different tab of the UITabBarController and back to the initial tab, this second destination's view is successfully rendered. It seems that switching tabs in this UITabBarController is calling something in either SwiftUI or UIKit that is redrawing my views. Conclusion This is a serious issue with UIKit + SwiftUI bridging support. I have never had problems like this until devices started running iOS 18.4, and there is nothing in the iOS 18.4 changelog that suggests this was an intentional change. All of a sudden, after updating to the latest iOS version, my app is totally broken. I want to be clear that I'm not using deprecated NavigationLink methods in these instances. My app's minimum deployment target is iOS 16. I know that there are more modern navigation APIs like navigation stack, etc. I am looking for answers about my use case: whether it is officially unsupported as of iOS 18.4, whether this setup should be supported and this is indeed some sort of bug in iOS, or anything in-between. I'm happy to provide formatted code if needed for discussion purposes. This is about my entire app's view hierarchy so there are a lot of disparate lines of code that make up this problem.
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Apr ’25
Infinite loop refreshing view with EnvironmentValue
Adding environment value openURL or dismiss to a View in a NavigationStack, without even using it, causes an infinite refresh loop. What doesn't work: a) struct ViewA: View { @State private var path = NavigationPath() var body: some View { NavigationStack(path: $path) { ViewB() } } } struct ViewB: View { @Environment(\.openURL) var openURL var body: some View { NavigationLink("Next", value: 1) .navigationDestination(for: Int.self, destination: itemView) } func itemView(_ item: Int) -> some View { Text("Item \(item)") } } Prints ViewB: _openURL changed. infinitely. b) Passing the path to ViewB and appending the value with a Button What works: a) .navigationDestination(for: Int.self) { Text("Item \($0)") } Prints ViewB: @self, @identity, _openURL changed. ViewB: @self, _openURL changed. ViewB: _openURL changed. (3 times) b) Handling the destination on ViewA, which is not ideal for my use case. Prints ViewB: @self, @identity, _openURL changed. ViewB: _openURL changed. (5 times) While the workaround would work, it is still unclear how the environment value can cause the freeze (and eventual crash). Also that passing a function as parameter fails, while providing the destination in place does not. The code is stripped down to the minimal reproducible version. Any thoughts?
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966
Mar ’25
SwiftUI Popover Crash During Resizing in Stage Manager
SwiftUI Popover Crash on iPad During Resizing in Stage Manager with Exception. *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Trying to layout popover in the delegate callback popoverPresentationController:willRepositionPopoverToRect:inView: will lead to recursion. Do not force the popover's container view or an ancestor to layout in this callback.' (Occurred from iPadOS 18.1) struct ContentView: View { @State var showPopover: Bool = false var body: some View { VStack { Text("Hello, world!") Button(action: { showPopover = true }, label: { Text("Open Popover") }) } .padding() .popover(isPresented: $showPopover, attachmentAnchor: .point(.trailing), content: { VStack { Text("Popover Content") } }) } }
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1.3k
Feb ’25
iOS 18 SwiftUI navigation bar problem
Okay I know, fill a bug... but here is a super simple app that will demostrate that the navigation bar chnages from Dark scheme to light scheme when you tap back after it goes to the second view. import SwiftUI struct ContentView: View { var body: some View { NavigationStack { NavigationLink { Text("Tap back and notice the navigation title changes to black text instead of white") .toolbarBackground(.visible, for: .navigationBar) .toolbarBackground(Color.orange, for: .navigationBar) .toolbarColorScheme(.dark, for: .navigationBar) } label: { VStack { Text("First page is the sweetest") } .padding() } .navigationTitle("First Page") .toolbarBackground(.visible, for: .navigationBar) .toolbarBackground(Color.orange, for: .navigationBar) .toolbarColorScheme(.dark, for: .navigationBar) } } } #Preview { ContentView() }
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4.7k
Feb ’25