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How do I pass a binding to a focus state?
In a SwiftUI lab, I was asking about setting the focus state down a view hierarchy. The answer I got was to pass the focus state down the views as a binding. Conceptually, that made sense, so I moved on to other questions. But now that I am trying to implement it, I am having problems. In the parent view, I have something like this: @FocusState private var focusElement: UUID? Then I am setting a property like this in the child view: @Binding var focusedId: UUID? When I try to create the detail view, I'm trying this: DetailView(focusedId: $focusElement) But this doesn't work. The error I get is: Cannot convert value of type 'FocusState<UUID?>.Binding' to expected argument type 'Binding<UUID?>' What is the right way to pass down the focus state to a child view so that it can update back up to the parent view? I am trying to update from one child view, and have a TextField in a sibling view get focus.
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13k
Jun ’21
How is Record Zone Sharing done?
My use case is the following: Every user of my app can create as an owner a set of items.  These items are private until the owner invites other users to share all of them as participant. The participants can modify the shared items and/or add other items. So, sharing is not done related to individual items, but to all items of an owner. I want to use CoreData & CloudKit to have local copies of private and shared items. To my understanding, CoreData & CloudKit puts all mirrored items in a special zone „com.apple.coredata.cloudkit.zone“. So, this zone should be shared, i.e. all items in it. In the video it is said that NSPersistentCloudKitContainer uses Record Zone Sharing optionally in contrast to hierarchically record sharing using a root record. But how is this done? Maybe I can declare zone „com.apple.coredata.cloudkit.zone“ as a shared zone?
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1k
Jun ’21
onGeometryChange: Assertion failed: Block was expected to execute on queue
Hello! After upgrading to Xcode 16 & Swift 6 & iOS 18 I starting receiveing strange crashes. Happens randomly in different view and pointing to onGeometryChange action block. I added DispatchQueue.main.async { in hopes it will help but it didn't. HStack { ... } .onGeometryChange(for: CGSize.self, of: \.size) { value in DispatchQueue.main.async { self.width = value.width self.height = value.height } } As far as I understand, onGeometryChange is defined as nonisolated and Swift 6 enforce thread checking for the closures, SwiftUI views are always run on the main thread. Does it mean we can not use onGeometryChange safely in swiftui? BUG IN CLIENT OF LIBDISPATCH: Assertion failed: Block was expected to execute on queue [com.apple.main-thread (0x1eacdce40)] Crashed: com.apple.SwiftUI.AsyncRenderer 0 libdispatch.dylib 0x64d8 _dispatch_assert_queue_fail + 120 1 libdispatch.dylib 0x6460 _dispatch_assert_queue_fail + 194 2 libswift_Concurrency.dylib 0x62b58 <redacted> + 284 3 Grit 0x3a57cc specialized implicit closure #1 in closure #1 in PurchaseModalOld.body.getter + 4377696204 (<compiler-generated>:4377696204) 4 SwiftUI 0x5841e0 <redacted> + 60 5 SwiftUI 0x5837f8 <redacted> + 20 6 SwiftUI 0x586b5c <redacted> + 84 7 SwiftUICore 0x68846c <redacted> + 48 8 SwiftUICore 0x686dd4 <redacted> + 16 9 SwiftUICore 0x6ecc74 <redacted> + 160 10 SwiftUICore 0x686224 <redacted> + 872 11 SwiftUICore 0x685e24 $s14AttributeGraph12StatefulRuleP7SwiftUIE15withObservation2doqd__qd__yKXE_tKlF + 72 12 SwiftUI 0x95450 <redacted> + 1392 13 SwiftUI 0x7e438 <redacted> + 32 14 AttributeGraph 0x952c AG::Graph::UpdateStack::update() + 540 15 AttributeGraph 0x90f0 AG::Graph::update_attribute(AG::data::ptr<AG::Node>, unsigned int) + 424 16 AttributeGraph 0x8cc4 AG::Subgraph::update(unsigned int) + 848 17 SwiftUICore 0x9eda58 <redacted> + 348 18 SwiftUICore 0x9edf70 <redacted> + 36 19 AttributeGraph 0x148c0 AGGraphWithMainThreadHandler + 60 20 SwiftUICore 0x9e7834 $s7SwiftUI9ViewGraphC18updateOutputsAsync2atAA11DisplayListV4list_AG7VersionV7versiontSgAA4TimeV_tF + 560 21 SwiftUICore 0x9e0fc0 $s7SwiftUI16ViewRendererHostPAAE11renderAsync8interval15targetTimestampAA4TimeVSgSd_AItF + 524 22 SwiftUI 0xecfdfc <redacted> + 220 23 SwiftUI 0x55c84 <redacted> + 312 24 SwiftUI 0x55b20 <redacted> + 60 25 QuartzCore 0xc7078 <redacted> + 48 26 QuartzCore 0xc52b4 <redacted> + 884 27 QuartzCore 0xc5cb4 <redacted> + 456 28 CoreFoundation 0x555dc <redacted> + 176 29 CoreFoundation 0x55518 <redacted> + 60 30 CoreFoundation 0x55438 <redacted> + 524 31 CoreFoundation 0x54284 <redacted> + 2248 32 CoreFoundation 0x535b8 CFRunLoopRunSpecific + 572 33 Foundation 0xb6f00 <redacted> + 212 34 Foundation 0xb6dd4 <redacted> + 64 35 SwiftUI 0x38bc80 <redacted> + 792 36 SwiftUI 0x1395d0 <redacted> + 72 37 Foundation 0xc8058 <redacted> + 724 38 libsystem_pthread.dylib 0x637c _pthread_start + 136 39 libsystem_pthread.dylib 0x1494 thread_start + 8
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1.2k
Sep ’24
UIDocumentPickerViewController provides corrupt copy of file when user taps multiple times on file
We're trying to implement a backup/restore data feature in our business productivity iPad app using UIDocumentPickerViewController and AppleArchive, but discovered odd behavior of [UIDocumentPickerViewController initForOpeningContentTypes: asCopy:YES] when reading large archive files from a USB drive. We've duplicated this behavior with iPadOS 16.6.1 and 17.7 when building our app with Xcode 15.4 targeting minimum deployment of iPadOS 16. We haven't tested this with bleeding edge iPadOS 18. Here's our Objective-C code which presents the picker: NSArray* contentTypeArray = @[UTTypeAppleArchive]; UIDocumentPickerViewController* docPickerVC = [[UIDocumentPickerViewController alloc] initForOpeningContentTypes:contentTypeArray asCopy:YES]; docPickerVC.delegate = self; docPickerVC.allowsMultipleSelection = NO; docPickerVC.shouldShowFileExtensions = YES; docPickerVC.modalPresentationStyle = UIModalPresentationPopover; docPickerVC.popoverPresentationController.sourceView = self.view; [self presentViewController:docPickerVC animated:YES completion:nil]; The UIDocumentPickerViewController remains visible until the selected external archive file has been copied from the USB drive to the app's local tmp sandbox. This may take several seconds due to the slow access speed of the USB drive. During this time the UIDocumentPickerViewController does NOT disable its tableview rows displaying files found on the USB drive. Even the most patient user will tap the desired filename a second (or third or fourth) time since the user's initial tap appears to have been ignored by UIDocumentPickerViewController, which lacks sufficient UI feedback showing it's busy copying the selected file. When the user taps the file a second time, UIDocumentPickerViewController apparently begins to copy the archive file once again. The end result is a truncated copy of the selected file based on the time between taps. For instance, a 788 MB source archive may be copied as a 56 MB file. Here, the UIDocumentPickerDelegate receives a 56 MB file instead of the original 788 MB of data. Not surprisingly, AppleArchive fails to decrypt the local copy of the archive because it's missing data. Instead of failing gracefully, AppleArchive crashes in AAArchiveStreamClose() (see forums post 765102 for details). Does anyone know if there's a workaround for this strange behavior of UIDocumentPickerViewController?
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1k
Sep ’24
Landscape safe area is incorrect when presenting SKStoreProductViewController
Hi. If the app is in landscape only and when the SKStoreProductViewController is presented, the safeArea changes to what looks like a portrait mode safe area. When the SKStoreProductViewController is dismissed, the safeArea does NOT revert back to the original values. Is there a way to force the safeArea to "reset"? I've submitted some bug tickets through Apple Feedback but I haven't received any response about it. The below code will pop up the SKStoreProductViewController and if you have a UIView that is constrained to the safe area, then you can visibly notice that the safe area is changed and doesn't go back. I have tested this on iPhone 14 Pro, iPhone 15, and iPhone 16 Pro and in the Simulators. The incorrect behavior happens on those and probably more. Thanks. #import "ViewController.h" #import &amp;lt;StoreKit/StoreKit.h&amp;gt; @interface ViewController () @property (nonatomic, strong) SKStoreProductViewController *productViewController; @end @implementation ViewController - (IBAction)buttonTapped:(id)sender { self.productViewController = [[SKStoreProductViewController alloc] init]; NSDictionary *parameters = @{ @"id" : @"6443575749" }; [self.productViewController loadProductWithParameters:parameters completionBlock:^(BOOL result, NSError * _Nullable error) { [self presentViewController:self.productViewController animated:YES completion:^{ // presented // The panel that is constraint to the safe area visibly shows that the safe area is no longer correct. }]; }]; } @end
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713
Nov ’24
PHPickerViewController No Auto Focus
The issue is, I cannot auto acquire bluetooth keyboard focus in PHPickerViewController after enabling 'Full Keyboard Access' in my IPhone 14 with iOS version 18.3.1. The keyboard focus in PHPickerViewController will show, however, after I tapped on the blank space of the PHPickerViewController. How to make the focus on at the first place then? I'm using UINavigationController and calling setNavigationBarHidden(true, animated: false). Then I use this controller to present PHPickerViewController using some configuration setup below. self.configuration = PHPickerConfiguration() configuration.filter = .any(of: filters) configuration.selectionLimit = selectionLimit if #available(iOS 15.0, *), allowOrdering { configuration.selection = .ordered } configuration.preferredAssetRepresentationMode = .current Finally I set the delegate to PHPickerViewController and call UINavigationController.present(PHPickerViewController, animated: true) to render it. Also I notice animation showing in first video then disappear.
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304
Mar ’25
Unexpected onAppear behavior in NavigationStack with ViewThatFits
Hello, My goal is to have a NavigationStack whose root view is determined based on its height and width. To do so, I'm using ViewThatFits, which should choose the right view to display. It is working fine, but unexpectedly both views trigger onAppear, whereas only the appropriate one should. This causes the logic in both closures to be executed, which is not intended. The code below demonstrates the problem: struct NavigationStackContentView: View { var body: some View { NavigationStack { ViewThatFits(in: .vertical) { Color.yellow .onAppear { print("|-> on appear: yellow") } .onDisappear { print("|-> on disappear: yellow") } Color.red .frame(width: 1500, height: 1500) .onAppear { print("|-> on appear: red") } .onDisappear { print("|-> on disappear: red") } } } } } this produces: |-> on appear: red |-> on disappear: red |-> on appear: yellow When ViewThatFits is not nested within NavigationStack, the problem does not occur — only the yellow view (in this sample) triggers onAppear, which is the expected behavior. I also checked the macOS version, and the problem does not occur at all, whether within NavigationStack or not. This example is simple and demonstrates that the larger view is the second one. When I switch their places, the problem does not occur because it recognizes that the first view would not fit at this point. However, in my case I will have these views without knowing which one will not fit, so switching their order is not a viable solution if this works without NavigationStack. Am I doing something wrong, or is this a bug? // iOS: 18.3.1 Xcode: 16.2
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204
Mar ’25
listRowSeparatorTint not updated
This sample code exhibits two issues: struct ContentView: View { @State private var myColor = Color.red var body: some View { VStack() { List() { Text("Object") Text("Object") Text("Object") .listRowSeparatorTint(myColor) Text("Object") } Button(action:{myColor = Color.green}) {Text("Change color")} } .foregroundColor(myColor) } } the row separator isn't redraws when the @State property change listRowSeparatorTint apply to two lines The first point is really disappointing. Is there anyone which know if this is a bug or there is a more correct way to use listRowSeparatorTint with changing parameter?
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176
Apr ’25
Get MacOS menubar size in Swift
To get menubar size, we can call. let menuBarHeight = NSStatusBar.system.thickness That is returning 24 and it is the same as my external screen. I did command + shift + 5 and use the screen capture tool to rougly measure the size of menubar. It is roughly 24px. However, for my macbook pro 14 inches m2 pro. The menubar seem thicker because of the webcam. Is there a way to find out the size in Swift?
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200
Apr ’25
memory leak/increased memory by NSTextField setString
I just put the TextField on UI and call the NSTextField setString, but it is memory usage is increasing. StoryBoard Objective C put TextField and button to UI set TextField variable to "ABC" in ViewController.h @property (weak) IBOutlet NSTextView* ABC; on button event function //dispatch_sync(dispatch_get_main_queue(), ^{ [_ABC setString:str]; //}); How to block the memory usage increase? Also I was check on Instruments app, and there are many malloc 48bytes, its count is almost same with setString count. Thank you!
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111
May ’25
The NSTextViewDelegate method textViewDidChangeSelection(:) will not fire, while all other text view delegate methods do.
I am trying to implement the NSTextViewDelegate function textViewDidChangeSelection(_ notification: Notification). My text view's delegate is the Coordinator of my NSViewRepresentable. I've found that this delegate function never fires, but any other delegate function that I implement, as long as it doesn't take a Notification as an argument, does fire (e.g., textView(:willChangeSelectionFromCharacterRange:toCharacterRange:), fires and is called on the delegate exactly when it should be). For context, I've verified all of the below: textView.isSelectable = true textView.isEditable = true textView.delegate === my coordinator I can call textViewDidChangeSelection(:) directly on the delegate without issue. I can select and edit text without issues. I.e., the selections are being set correctly. But the delegate method is never called when they are. I am able to add the intended delegate as an observer for the selector textViewDidChangeSelection via NotificationCenter. If I do this, the function executes when it should, but fires for every text view in my view hierarchy, which can number in the hundreds. I'm using an NSLayoutManager, so I figure this should only fire once. I've added a check within my code: func textViewDidChangeSelection(_ notification: Notification) { guard let textView = notification.object as? NSTextView, textView === layoutManager.firstTextView else { return } // Any code I want to execute... } But the above guard check lets through every notification, so, no matter what, my closure executes hundreds of times if I have hundreds of text views, all of them being sent by textView === layoutManager.firstTextView, but once for each and every text view managed by that layoutManager. Does anyone know why this method isn't ever called on the delegate, while seemingly all other delegate methods are? I could go the NotificationCenter route, but I'd love to know why this won't execute as a delegate method when documentation says that it should, and I don't want to have to implement a counter to make sure my code only executes once per selection update. And for more reasons than that, implementing via delegate method is preferable to using notifications for my use case. Thanks for any help!
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185
May ’25
Using .glassEffect in Charts
Hi, I was wondering if it's possible (and advisable) to use the new glass effects available in iOS 26 in Swift Charts? For example, in a chart like the one in the image I've attached to this post, I was looking to try adding a .glassEffect modifier to the BarMarks to see how that would look and feel. However, it seems it's not available directly on the BarMark (ChartContent) type, and I'm having trouble adding it in other ways too, such as using in on the types I supply to modifiers like foregroundStyle or clipShape. Am I missing anything? Maybe it's just not advisable or necessary to use glass effects within Charts?
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273
Jun ’25
Issues with .zoom NavigationTransition to a sheet with a .medium detent
When using a .zoom navigation transition, where .matchedTransitionSource is applied to a button in a toolbar and the destination view is a sheet which is presented with PresentationDetent.medium, the transition works initially, but shortly after it completes, the sheet's background is dimmed and the text of the source button reappears abruptly. Code and a screenshot are below, though the effect is best observed when interacting with the view. // // ContentView.swift // ZoomNavigationTransitionSample // // Created by Matthew DuBois on 6/15/25. // import SwiftUI struct ContentView: View { @State private var isPresentingSheet = false @Namespace private var namespace var body: some View { NavigationStack { List { Text("Some content") } .navigationTitle("Sample") .toolbar { ToolbarItem(placement: .topBarTrailing) { Button("Button") { isPresentingSheet = true } .matchedTransitionSource(id: "button", in: namespace) } } .sheet(isPresented: $isPresentingSheet) { Text("Some sheet content") .navigationTransition(.zoom(sourceID: "button", in: namespace)) .presentationDetents([.medium]) } } } } #Preview { ContentView() }
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120
Jun ’25
encounter memory leak for SVG image
I have a memory leak for SVG image that located in Assets.xcassets file when using SwiftUI Image, but when I use UIImage then convert it to SwiftUI Image the issue is not found. import SwiftUI struct ContentView: View { var body: some View { NavigationStack { VStack { NavigationLink("Show", destination: SecondView()) } .padding() } } } struct SecondView: View { @Environment(\.dismiss) var dismiss var body: some View { NavigationStack { VStack { IM.svgImage .resizable() .scaledToFit() .frame(width: 200, height: 200) Button("Dismiss") { dismiss() } } } } } enum IM { static let testImage: Image = "test_image".image static let svgImage: Image = "svgImage".image } extension String { var image: Image { Image(self) // Memory leak } var imageFromUIImage: Image { guard let uiImage = UIImage(named: self) else { return Image(self) } return Image(uiImage: uiImage) // No Memory leak } } Environment that produces the issue: Xcode: 16.2 Simulator: iPhone 15 Pro (iOS 17.5)
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118
Jun ’25
SwiftUI buttons behind NSToolbarView are not clickable on macOS 26 beta
Overview Starting with macOS 26 beta 1, a new NSGlassContainerView is added inside NSToolbarView. This view intercepts mouse events, so any SwiftUI Button (or other interactive view) overlaid on the title‑bar / toolbar area no longer receives clicks. (The same code works fine on macOS 15 and earlier.) Filed as FB18201935 via Feedback Assistant. Reproduction (minimal project) macOS 15 or earlier → button is clickable macOS 26 beta → button cannot be clicked (no highlight, no action call) @main struct Test_macOS26App: App { init() { // Uncomment to work around the issue (see next section) // enableToolbarClickThrough() } var body: some Scene { WindowGroup { ContentView() } .windowStyle(.hiddenTitleBar) // ⭐️ hide the title bar } } struct ContentView: View { var body: some View { NavigationSplitView { List { Text("sidebar") } } detail: { HSplitView { listWithOverlay listWithOverlay } } } private var listWithOverlay: some View { List(0..<30) { Text("item: \($0)") } .overlay(alignment: .topTrailing) { // ⭐️ overlay in the toolbar area Button("test") { print("test") } .glassEffect() .ignoresSafeArea() } } } Investigation In Xcode View Hierarchy Debugger, a layer chain NSToolbarView > NSGlassContainerView sits in front of the button. -[NSView hitTest:] on NSGlassContainerView returns itself, so the event never reaches the SwiftUI layer. Swizzling hitTest: to return nil when the result is the view itself makes the click go through: func enableToolbarClickThrough() { guard let cls = NSClassFromString("NSGlassContainerView"), let m = class_getInstanceMethod(cls, #selector(NSView.hitTest(_:))) else { return } typealias Fn = @convention(c)(AnyObject, Selector, NSPoint) -> Unmanaged<NSView>? let origIMP = unsafeBitCast(method_getImplementation(m), to: Fn.self) let block: @convention(block)(AnyObject, NSPoint) -> NSView? = { obj, pt in guard let v = origIMP(obj, #selector(NSView.hitTest(_:)), pt)?.takeUnretainedValue() else { return nil } return v === (obj as AnyObject) ? nil : v // ★ make the container transparent } method_setImplementation(m, imp_implementationWithBlock(block)) } Questions / Call for Feedback Is this an intentional behavioral change? If so, what is the recommended public API or pattern for allowing clicks to reach views overlaid behind the toolbar? Any additional data points or confirmations are welcome—please reply if you can reproduce the issue or know of an official workaround. Thanks in advance!
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271
Jun ’25
UINavigationController retain cycle in iOS 26
Verbatim of a feedback report (FB18431713) I submitted, duplicated here since we can't see each other's feedbacks, and I wanted a centralized place to track the resolution of this as I'm surely not the only one facing this. When building the app using Xcode 26 beta 2 and running it in an iOS 26 simulator, I'm experiencing a retain cycle in the UINavigationController. From the data I saw in Xcode's memory graph debugger, it seems that _UIViewControllerOneToOneTransitionContext is retaining it. I base this on the fact that the line connecting a view controller and _UIViewControllerOneToOneTransitionContext has a "strong" reference, as indicated in Xcode. (However, I'm reporting this as a retain cycle in UINavigationController, as that's what seems to hold onto this transition-context.)
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180
Jun ’25