Construct and manage graphical, event-driven user interfaces for iOS or tvOS apps using UIKit.

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How to add view below navigation bar to extend scroll edge effect
Hello! What UIKit API enables you to add a view below the navigation bar and extend the scroll edge effect below it in iOS 26? safeAreaBar is how you do it in SwiftUI but I need to achieve this design in my UIKit app (which has a collection view in a view controller in a navigation controller). struct ContentView: View { let segments = ["First", "Second", "Third"] @State private var selectedSegment = "First" var body: some View { NavigationStack { List(0..<50, id: \.self) { i in Text("Row \(i + 1)") } .safeAreaBar(edge: .top) { Picker("Segment", selection: $selectedSegment) { ForEach(segments, id: \.self) { Text($0) } } .pickerStyle(.segmented) .padding(.horizontal) .padding(.bottom, 8) } .navigationTitle("Title") .navigationBarTitleDisplayMode(.inline) } } }
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Navigation Bar Elements Disappear When Using UIPageViewController in SwiftUI Under Low Power Mode
Problem Description: In a SwiftUI application, I've wrapped UIKit's UIPageViewController using UIViewControllerRepresentable, naming the wrapped class PagedInfiniteScrollView. This component causes navigation bar elements (title and buttons) to disappear. This issue only occurs in Low Power Mode on a physical device. Steps to Reproduce: Enable Low Power Mode on a physical device and open the app's home page. From the home page, open a detail sheet containing PagedInfiniteScrollView. This detail page include a navigation title and a toolbar button in the top-right corner. PagedInfiniteScrollView supports horizontal swiping to switch pages. Tap the toolbar button in the top-right corner of the detail page to open an edit sheet. Without making any changes, close the edit sheet and return to the detail page. On the detail page, swipe left and right on the PagedInfiniteScrollView. Expected Result: When swiping the PagedInfiniteScrollView, the navigation title and top-right toolbar button of the detail page should remain visible. Actual Result: When swiping the PagedInfiniteScrollView, the navigation title and top-right toolbar button of the detail page disappear. import SwiftUI @main struct CalendarApp: App { var body: some Scene { WindowGroup { ContentView() } } } import SwiftUI struct ContentView: View { @State private var showDetailSheet = false @State private var currentPage: Int = 0 var body: some View { NavigationStack { Button { showDetailSheet = true } label: { Text("show Calendar sheet") } .sheet(isPresented: $showDetailSheet) { DetailSheet(currentPage: $currentPage) } } } } struct DetailSheet: View { @Binding var currentPage: Int @State private var showEditSheet = false var body: some View { NavigationStack { PagedInfiniteScrollView(content: { pageIndex in Text("\(pageIndex)") .frame(width: 200, height: 200) .background(Color.blue) }, currentPage: $currentPage) .sheet(isPresented: $showEditSheet, content: { Text("edit") }) .navigationTitle("Detail") .navigationBarTitleDisplayMode(.inline) .toolbar { ToolbarItemGroup(placement: .topBarTrailing) { Button { showEditSheet = true } label: { Text("Edit") } } } } } } import SwiftUI import UIKit struct PagedInfiniteScrollView<Content: View>: UIViewControllerRepresentable { typealias UIViewControllerType = UIPageViewController let content: (Int) -> Content @Binding var currentPage: Int func makeCoordinator() -> Coordinator { Coordinator(self) } func makeUIViewController(context: Context) -> UIPageViewController { let pageViewController = UIPageViewController(transitionStyle: .scroll, navigationOrientation: .horizontal) pageViewController.dataSource = context.coordinator pageViewController.delegate = context.coordinator let initialViewController = UIHostingController(rootView: IdentifiableContent(index: currentPage, content: { content(currentPage) })) pageViewController.setViewControllers([initialViewController], direction: .forward, animated: false, completion: nil) return pageViewController } func updateUIViewController(_ uiViewController: UIPageViewController, context: Context) { let currentViewController = uiViewController.viewControllers?.first as? UIHostingController<IdentifiableContent<Content>> let currentIndex = currentViewController?.rootView.index ?? 0 if currentPage != currentIndex { let direction: UIPageViewController.NavigationDirection = currentPage > currentIndex ? .forward : .reverse let newViewController = UIHostingController(rootView: IdentifiableContent(index: currentPage, content: { content(currentPage) })) uiViewController.setViewControllers([newViewController], direction: direction, animated: true, completion: nil) } } class Coordinator: NSObject, UIPageViewControllerDataSource, UIPageViewControllerDelegate { var parent: PagedInfiniteScrollView init(_ parent: PagedInfiniteScrollView) { self.parent = parent } func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? { guard let currentView = viewController as? UIHostingController<IdentifiableContent<Content>>, let currentIndex = currentView.rootView.index as Int? else { return nil } let previousIndex = currentIndex - 1 return UIHostingController(rootView: IdentifiableContent(index: previousIndex, content: { parent.content(previousIndex) })) } func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController? { guard let currentView = viewController as? UIHostingController<IdentifiableContent<Content>>, let currentIndex = currentView.rootView.index as Int? else { return nil } let nextIndex = currentIndex + 1 return UIHostingController(rootView: IdentifiableContent(index: nextIndex, content: { parent.content(nextIndex) })) } func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) { if completed, let currentView = pageViewController.viewControllers?.first as? UIHostingController<IdentifiableContent<Content>>, let currentIndex = currentView.rootView.index as Int? { parent.currentPage = currentIndex } } } } extension PagedInfiniteScrollView { struct IdentifiableContent<Content: View>: View { let index: Int let content: Content init(index: Int, @ViewBuilder content: () -> Content) { self.index = index self.content = content() } var body: some View { content } } }
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Liquid Glass TabBar animations causes Hangs, bug with UIKitCore?
With iOS 26.1 we started seeing a bug that only appears on iPhone Air. This bug is visible with simulators too. I have tried so many different ways to fix the issue, but Instruments Profiler is pointing at UIKitCore. We load a tab bar, when the user attempts to switch a tab, the app hangs and never recovers. It happens right as the animation of the Glass bubble is in progress. I have tried a UIKit Tab bar, a SwiftUI Tab bar. I tore out AppDelegate and did a direct @main SwiftUI entry for my application. This issue appears with every tab bar instance I try. I attempted to disable LiquidGlass by utilizing this flag UIDesignRequiresCompatibility in my plist, but the flag seems to be ignored by the system. I am not sure what else to try. I have a trace file if that is helpful. What else can I upload? Here is what the code looks like. struct ContentView: View { @State private var selectedTab = 2 var body: some View { TabView(selection: $selectedTab) { Text("Profile") .tabItem { Label("Me", systemImage: "person") } .tag(0) Text("Training") .tabItem { Label("Training", systemImage: "calendar") } .tag(1) Text("Home") .tabItem { Label("Home", systemImage: "house") } .tag(2) Text("Goals") .tabItem { Label("Goals", systemImage: "target") } .tag(3) Text("Coach") .tabItem { Label("Coach", systemImage: "person.2") } .tag(4) } } } #Preview { ContentView() } and AppView entry point import SwiftUI @main struct RunCoachApp: App { var body: some Scene { WindowGroup { ContentView() } } }
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How to prevent window scene restoration
We have an iOS app running on macOS (not Mac Catalyst). The preferences are in a dedicated UIWindowScene. We don't want this scene to be restored, so when you start the app the preferences shouldn't be visible. How can we prevent the UIWindowScene restoration? Alternatively, if we can't prevent it, how can we ensure the main window scene is in front of the preferences window scene on app start?
Topic: UI Frameworks SubTopic: UIKit Tags:
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iOS26 UISearchbar and UISearchController cancellation issues
Is the Cancel button intentionally removed from UISearchBar (right side)? Even when using searchController with navigationItem also. showsCancelButton = true doesn’t display the cancel button. Also: When tapping the clear ("x") button inside the search field, the search is getting canceled, and searchBarCancelButtonClicked(_:) is triggered (Generally it should only clear text, not cancel search). If the search text is empty and I tap outside the search bar, the search is canceled. Also when I have tableview in my controller(like recent searches) below search bar and if I try to tap when editing started, action is not triggered(verified in sample too). Just cancellation is happening. In a split view controller, if the search is on the right side and I try to open the side panel, the search also gets canceled. Are these behaviors intentional changes, beta issues, or are we missing something in implementation?
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How to move focus across multiple textfields using arrow keys/enter key in iOS
Hi. I have an iOS application with multiple input fields. I have to design an experience such that whenever the user presses enter key on a textfield, it should move focus to the next input field. Similarly, consider a stack of 3 textfields, I want to cycle the focus as and when the user presses up/down arrow keys. Other platforms like Android, have this feature out-of-the-box. I wanted to understand if iOS also supports this kind of behavior. I know how to manually code such UX, but just wanted to confirm whether there is some inherent feature like on android which i can leverage? Thanks.
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UITabBar ignores font in iOS 26.2
Our app has a UITabBar and the compactInlineLayoutAppearance has a custom font set. This worked fine on iOS 26.0 and 26.1. [self.bottomTabBar.standardAppearance.compactInlineLayoutAppearance.normal setTitleTextAttributes: @{ NSFontAttributeName:[UIFont fontWithName:@"AvenirNext-DemiBold" size:18.0] }]; But on iOS 26.2, the system ignores this custom font. How can I apply a custom font to a UITabBar on iOS 26.2?
Topic: UI Frameworks SubTopic: UIKit Tags:
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UITabBar Appears During Swipe-Back Gesture on iOS 26 Liquid Glass UI
Hello, While integrating the Liquid Glass UI introduced in iOS 26 into my existing app, I encountered an unexpected issue. My app uses a UITabBarController, where each tab contains a UINavigationController, and the actual content resides in each UIViewController. Typically, I perform navigation using navigationController?.pushViewController(...) and hide the TabBar by setting vc.hidesBottomBarWhenPushed = true when needed. This structure worked perfectly fine prior to iOS 26, and I believe many apps use a similar approach. However, after enabling Liquid Glass UI, a problem occurs. Problem Description From AViewController, I push BViewController with hidesBottomBarWhenPushed = true. BViewController appears, and the TabBar is hidden as expected. When performing a swipe-back gesture, as soon as AViewController becomes visible, the TabBar immediately reappears (likely due to A’s viewWillAppear). The TabBar remains visible for a short moment even if the gesture is canceled — during that time, it is also interactable. Before iOS 26, the TabBar appeared synchronized with AViewController and did not prematurely show during the swipe transition. Tried using the new iOS 18 API: tabBarController?.setTabBarHidden(false, animated: true) It slightly improves the animation behavior, but the issue persists. If hidesBottomBarWhenPushed is now deprecated or discouraged, migrating entirely to setTabBarHidden would require significant refactoring, which is not practical for many existing apps. Is this caused by a misuse of hidesBottomBarWhenPushed, or could this be a regression or design change in iOS 26’s Liquid Glass UI?
Topic: UI Frameworks SubTopic: UIKit Tags:
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Incorrect system color on popover view, and does not update while switching dark mode on iOS 26 beta 3
All system colors are displayed incorrectly on the popover view. Those are the same views present as a popover in light and dark mode. And those are the same views present as modal. And there is also a problem that when the popover is presented, switching to dark/light mode will not change the appearance. That affected all system apps. The following screenshot is already in dark mode. All those problem are occured on iOS 26 beta 3.
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CoreAutoLayout -[NSISEngine _flushPendingRemovals] crash
crash stack: Crashed: com.apple.main-thread 0 libsystem_pthread.dylib 0x90c thread_chkstk_darwin + 60 1 libsystem_pthread.dylib 0x90c ___chkstk_darwin + 60 2 CoreAutoLayout 0x14c4 -[NSISEngine _flushPendingRemovals] + 56 3 CoreAutoLayout 0x2de08 -[NSISEngine _coreReplaceMarker:withMarkerPlusDelta:].cold.1 + 64 4 CoreAutoLayout 0x15d78 -[NSISEngine _coreReplaceMarker:withMarkerPlusDelta:] + 204 5 CoreAutoLayout 0x2ce38 -[NSISEngine constraintDidChangeSuchThatMarker:shouldBeReplacedByMarkerPlusDelta:] + 108 6 CoreAutoLayout 0x15f1c -[NSISEngine tryToChangeConstraintSuchThatMarker:isReplacedByMarkerPlusDelta:undoHandler:] + 100 7 CoreAutoLayout 0x2fdbc -[NSLayoutConstraint _tryToChangeContainerGeometryWithUndoHandler:] + 252 8 CoreAutoLayout 0x3020c -[NSLayoutConstraint _setSymbolicConstant:constant:symbolicConstantMultiplier:] + 452 9 CoreAutoLayout 0x30378 -[NSLayoutConstraint setConstant:] + 84 10 UIKitCore 0x51c3c __74-[UIView(UIConstraintBasedLayout) _autoresizingConstraints_frameDidChange]_block_invoke + 140 11 UIKitCore 0x1841174 -[UIView(AdditionalLayoutSupport) _withUnsatisfiableConstraintsLoggingSuspendedIfEngineDelegateExists:] + 112 12 UIKitCore 0x51b28 -[UIView(UIConstraintBasedLayout) _autoresizingConstraints_frameDidChange] + 452 13 UIKitCore 0x2c894 -[UIView _constraints_frameDidChange] + 100 14 UIKitCore 0x18fac08 -[UIView(Geometry) setFrame:] + 576 15 UIKitCore 0x96712c -[UITabBar setFrame:] + 128 16 UIKitCore 0x1666f4 -[_UITabBarControllerVisualStyle updateTabBarLayout] + 360 17 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 18 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 19 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 20 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 21 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 22 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 23 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 24 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 25 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 26 UIKitCore 0x16671c -[_UITabBarControllerVisualStyle updateTabBarLayout] + 400 27 UIKitCore 0x16642c -[UITabBarController _prepareTabBar] + 128 28 UIKitCore 0x166a10 -[UITabBarController _layoutContainerView] + 376 29 UIKitCore 0x1677a8 -[UITabBarController __viewWillLayoutSubviews] + 28 30 UIKitCore 0x147078 -[UILayoutContainerView layoutSubviews] + 176 31 UIKit 0xb14a0 -[UILayoutContainerViewAccessibility layoutSubviews] + 60 for a more detail crash stack, can see attach file: crash.txt crash probabilistic happed after app enter background, and our app support landscape, when crash appear, the system method: /* This method is called when the view controller's view's size is changed by its parent (i.e. for the root view controller when its window rotates or is resized). If you override this method, you should either call super to propagate the change to children or manually forward the change to children. */ - (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id <UIViewControllerTransitionCoordinator>)coordinator API_AVAILABLE(ios(8.0)); is called; but for a normal not crash case, when enter background and rotate device, the viewWillTransitionToSize method is not called until app enter foreground; Are there any suggestions that can help solve this problem, thank you.
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Xcode26+iOS26系统,UICollectionView的reloadData不会触发调用UICollectionViewCell的layoutSubviews方法。
问题场景: Xcode26+iOS26系统,UICollectionView的reloadData不会触发调用UICollectionViewCell的layoutSubviews方法。 正常场景: Xcode26+iOS18及以下系统,UICollectionView的reloadData能够触发调用UICollectionViewCell的layoutSubviews方法。 UITableView的reloadData,会正常调用UITableViewCell的layoutSubviews方法。
Topic: UI Frameworks SubTopic: UIKit Tags:
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How to Implement Dynamic Type for UITextFields Without Resetting Data
Hello! I was doing some accessibility testing for my app and found out that when the user switches the text size, all of the data in the text fields is reset, which causes major disruption. I've tried looking for documentation, but all I've found is information on how to dynamically scale the UI for different text sizes, which I've already implemented. My guess is that every time Dynamic Type registers a change, it redraws my UI instead of just updating it. How can I make sure the data is not reset when the text size changes?
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iOS 18.1 crash UIHostingView.layoutSubviews() / swift_unknownObjectWeakAssign / objc_storeWeak
We're seeing sporadic crashes on devices running iOS 18.1 - both beta and release builds (22B83). The stack trace is always identical, a snippet of it below. As you can tell from the trace, it's happening in places we embed SwiftUI into UIKit via UIHostingController. Anyone else seeing this? 4 libobjc.A.dylib 0xbe2c _objc_fatalv(unsigned long long, unsigned long long, char const*, char*) + 30 5 libobjc.A.dylib 0xb040 weak_register_no_lock + 396 6 libobjc.A.dylib 0xac50 objc_storeWeak + 472 7 libswiftCore.dylib 0x43ac34 swift_unknownObjectWeakAssign + 24 8 SwiftUI 0xeb74c8 _UIHostingView.base.getter + 160 9 SwiftUI 0x92124 _UIHostingView.layoutSubviews() + 112 10 SwiftUI 0x47860 @objc _UIHostingView.layoutSubviews() + 36
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Menu presentation in UIHostingController issues
Looking to see if anyone has experienced this issue, and is aware of any workarounds. With an app migrating towards SwiftUI Views but still using UIKit for primary navigation, my app makes use of UIHostingController to push SwiftUI Views onto a UINavigationController stack in a lot of areas. With iOS 26, I notice that SwiftUI's Menu view really struggles to present when contained in a UIHostingController. An error is logged to the console on presentation, and depending on the UI, the Menu won't present inside of it's container, or will jump around the screen. The bug, it seems is based in a private class UIReparentingView and I am curious if anyone has found a work around for this issue. The error reported is: Adding '_UIReparentingView' as a subview of UIHostingController.view is not supported and may result in a broken view hierarchy. Add your view above UIHostingController.view in a common superview or insert it into your SwiftUI content in a UIViewRepresentable instead. The simplest way to see this issue is to create a new storyboard based project. From the ViewController present a UIHostingController with a SwiftUI view that has a Menu and then simply tap to open the Menu. Thanks for any input!
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AVPlayer loading performance problem in iOS 26
Hi, I have an app that displays tens of short (<1mb) mp4 videos stored in a remote server in a vertical UICollectionView that has horizontally scrollable sections. I'm caching all mp4 files on disk after downloading, and I also have a in-memory cache that holds a limited number (around 30) of players. The players I'm using are simple views that wrap an AVPlayerLayer and its AVPlayerItem, along with a few additional UI components. The scrolling performance was good before iOS 26, but with the release of iOS 26, I noticed that there is significant stuttering during scrolling while creating players with a fileUrl. It happens even if use the same video file cached on disk for each cell for testing. I also started getting this kind of log messages after the players are deinitialized: <<<< PlayerRemoteXPC >>>> signalled err=-12785 at <>:1107 <<<< PlayerRemoteXPC >>>> signalled err=-12785 at <>:1095 <<<< PlayerRemoteXPC >>>> signalled err=-12785 at <>:1095 There's also another log message that I see occasionally, but I don't know what triggers it. << FigXPC >> signalled err=-16152 at <>:1683 Is there anyone else that experienced this kind of problem with the latest release? Also, I'm wondering what's the best way to resolve the issue. I could increase the size of the memory cache to something large like 100, but I'm not sure if it is an acceptable solution because: 1- There will be 100 player instance in memory at all times. 2- There will still be stuttering during the initial loading of the videos from the web. Any help is appreciated!
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Detecting marked range in UI/NSTextViews at the time of shouldChangeTextIn
We have submitted a feedback for this issue: FB21230723 We're building a note-taking app for iOS and macOS that uses both UITextView and NSTextView. When performing text input that involves a marked range (such as Japanese input) in a UITextView or NSTextView with a UITextViewDelegate or NSTextViewDelegate set, the text view's marked range (markedTextRange / markedRange()) has not yet been updated at the moment when shouldChangeTextIn is invoked. UITextViewDelegate.textView(_:shouldChangeTextIn:replacementText:) NSTextViewDelegate.textView(_:shouldChangeTextIn:replacementString:) The current behavior is this when entering text in Japanese: (same for NSTextView) func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool { print(textView.markedTextRange != nil) // prints out false DispatchQueue.main.async { print(textView.markedTextRange != nil) // prints out true } } However, we need the value of markedTextRange right away in order to determine whether to return true or false from this method. Is there any workaround for this issue?
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Unwanted animations appear on UIButton (iOS 26)
After the iOS 26 update, unwanted animations appear on UIButton. I'm using the attributedTitle property of UIButton.Configuration to change the button's text, and an animation appears after iOS 26. (It's unclear whether it's after iOS 26.0 or iOS 26.1, but it likely started with 26.1.) The peculiar thing is that the animation only starts appearing on buttons that have been pressed once. I tried using UIView.performWithoutAnimation and CATransaction's begin(), setDisableActions(true), commit(), but it didn't work. How should I solve this? Below is the code for changing the button's text. func updateTitle() { let keys = type.keys if keys.count == 1 { guard let key = keys.first else { return } if key.count == 1 { if Character(key).isLowercase { self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 24, weight: .regular), .foregroundColor: UIColor.label])) } else if Character(key).isUppercase { self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 22, weight: .regular), .foregroundColor: UIColor.label])) } else { self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 22, weight: .regular), .foregroundColor: UIColor.label])) } } else { self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 18, weight: .regular), .foregroundColor: UIColor.label])) } } else { let joined = keys.joined(separator: "") self.configuration?.attributedTitle = AttributedString(joined, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 22, weight: .regular), .foregroundColor: UIColor.label])) } }
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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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