Explore the various UI frameworks available for building app interfaces. Discuss the use cases for different frameworks, share best practices, and get help with specific framework-related questions.

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SwiftData/ModelSnapshot.swift:46: Fatal error: A ModelSnapshot must be initialized with a known-keys dictionary
I'm running into a crash when trying to delete an item from a list that's loaded using SwiftData. The app works fine when selecting or displaying the data, but the moment I confirm a deletion, it crashes with this error: SwiftData/ModelSnapshot.swift:46: Fatal error: A ModelSnapshot must be initialized with a known-keys dictionary This happens right after I delete an item from the list using modelContext.delete(). I’ve double-checked that the item exists and is valid, and I'm not sure what I'm doing wrong. The data is loaded using @Query and everything seems normal until deletion. For further information, I have tried this on a new IOS project where I have one super Model class with a cascading relationship on a child class. When trying to delete the parent class while connected to one or more children, it still gives me the error. The same thing is happening with my original project. Class A has a relationship (cascading) with Class B. Attempting to delete Class A while there are relationships with Class B throws this error. If anyone has experienced this or knows what causes it, please let me know. I’m not even sure where to start debugging this one. Thanks in advance!
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245
May ’25
ScreenBlur is not happening always when app goes to app switcher.
We have written code to blur the app screen in "applicationWillResignActive" when app goes to app switcher. But the blur affect is observed only some times. Is there is any specific reason for this? We have a doubt that applicationWillResignActive is not always completely executed or is dismissed by OS for other priority activities. Is this is expected behaviour or are we missing anything here?
Topic: UI Frameworks SubTopic: UIKit
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302
May ’25
Regarding ARKit camera feed zoom and macro support for closer object
I am currently developing an AR experience using ARKit with SceneKit and am looking to implement functionality that enables: Zooming into the AR camera feed, ideally leveraging the ultra-wide or telephoto lenses available on supported devices. Macro-style focus capabilities, allowing users to view and interact with virtual content closely aligned with small or nearby real-world objects (within a few centimeters). My objective is to ensure that ARKit continues to render the scene accurately while enabling a zoomed-in view or macro-level focus for better detail visibility and alignment. Could you please advise on: Whether ARKit currently supports camera zoom or allows access to macro or ultra-wide cameras within an ARSession. Limitations or considerations when using multi-camera setups in conjunction with ARKit. Any guidance or references to documentation or sample code would be greatly appreciated. Best regards, Ayush
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191
May ’25
ARKit Camera Feed Zoom & Macro Support for Close-Range Objects
I am currently developing an AR experience using ARKit with SceneKit and am looking to implement functionality that enables: Zooming into the AR camera feed, ideally leveraging the ultra-wide or telephoto lenses available on supported devices. Macro-style focus capabilities, allowing users to view and interact with virtual content closely aligned with small or nearby real-world objects (within a few centimeters). My objective is to ensure that ARKit continues to render the scene accurately while enabling a zoomed-in view or macro-level focus for better detail visibility and alignment. Could you please advise on: Whether ARKit currently supports camera zoom or allows access to macro or ultra-wide cameras within an ARSession. Limitations or considerations when using multi-camera setups in conjunction with ARKit. Any guidance or references to documentation or sample code would be greatly appreciated.
0
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238
May ’25
Room Plan Issue (structure.capturedStructure)
Hi everyone, My app crashed when using the merge room feature. I suspect the issue might be caused by a wall having more than 4 edges. Has anyone experienced a similar problem and found a solution? I’d really appreciate any advice or suggestions. Thank you all, and have a great day! let capturedStructure = try await structure.capturedStructure(from: self.rooms)
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278
May ’25
[StoreKit] Runtime warning with manageSubscriptionsSheet and ObservableObject
The following runtime warning is emitted by Xcode when using the manageSubscriptionsSheet with an ObservableObject: \ContentViewModel.isPresented is isolated to the main actor. Accessing it via Binding from a different actor will cause undefined behaviors, and potential data races; This warning will become a runtime crash in a future version of SwiftUI. Publishing changes from background threads is not allowed; make sure to publish values from the main thread (via operators like receive(on:)) on model updates. This minimal sample project reproduces the issue: class ContentViewModel: ObservableObject { @Published var isPresented = false func didTapButton() { self.isPresented = true } } struct ContentView: View { @ObservedObject var viewModel: ContentViewModel var body: some View { Button("Tap me") { self.viewModel.didTapButton() } .manageSubscriptionsSheet(isPresented: self.$viewModel.isPresented) } } Reproduced on: Xcode 16.2 Xcode 16.3 beta both with a simulator and a real device. This doesn't happen when using @Observable.
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288
May ’25
Deadline for Adopting Scene-Based Life-Cycle in UIKit Apps
I found the following statement on the site https://developer.apple.com/documentation/technotes/tn3187-migrating-to-the-uikit-scene-based-life-cycle: "Soon, all UIKit based apps will be required to adopt the scene-based life-cycle, after which your app won’t launch if you don’t. While supporting multiple scenes is encouraged, only adoption of scene life-cycle is required." Could you please clarify when exactly apps will no longer be able to launch if they do not adopt the scene-based life-cycle? I would like to confirm the deadline as the impact of this change is significant.
Topic: UI Frameworks SubTopic: UIKit Tags:
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328
May ’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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134
May ’25
Crash when minimizing on external display and unplugging it (iOS App on Mac)
Our iOS app, when running as an iOS App on Mac, crashes consistently under the following scenario: 1. Launch the app on an external display. 2. Minimize the app window. 3. Disconnect the external display. The app crashes every time under these conditions. The crash log shows the following call stack: *** Assertion failure in -[UINSWorkspace _maximumContentSizeForWindowOnScreen:], UINSWorkspace.m:401 -[UINSWorkspace _maximumContentSizeForWindowOnScreen:]: screen parameter should not be nil ( 0 CoreFoundation 0x000000018e841df0 __exceptionPreprocess + 176 1 libobjc.A.dylib 0x000000018e306b60 objc_exception_throw + 88 2 Foundation 0x000000018fb6aa78 -[NSCalendarDate initWithCoder:] + 0 3 UIKitMacHelper 0x00000001a9a59110 -[UINSWorkspace _maximumContentSizeForWindowOnScreen:] + 184 4 UIKitMacHelper 0x00000001a9a3e748 -[UINSSceneViewController _usableScreenSizeWithSceneSize:shouldOverride:] + 412 5 UIKitMacHelper 0x00000001a9a3d55c -[UINSSceneViewController _effectiveScaleFactorForLayoutWithOverride:] + 88 6 UIKitMacHelper 0x00000001a9a3f3a8 -[UINSSceneViewController _updateZoomFactors] + 28 7 UIKitMacHelper 0x00000001a9a3f248 -[UINSSceneViewController _updateZoomFactorsAndDoLayout] + 24 8 UIKitMacHelper 0x00000001a9a3df80 -[UINSSceneViewController _doUpdates:] + 104 9 UIKitMacHelper 0x00000001a99ad460 -[UINSSceneViewController observeValueForKeyPath:ofObject:change:context:] + 176 10 Foundation 0x000000018facb0d8 -[NSKeyValueObservance observeValueForKeyPath:ofObject:change:context:] + 388 11 Foundation 0x000000018facb0d8 -[NSKeyValueObservance observeValueForKeyPath:ofObject:change:context:] + 388 12 Foundation 0x000000018fa8f7b4 NSKeyValueNotifyObserver + 252 13 Foundation 0x000000018fb3c560 NSKeyValueDidChange + 388 14 Foundation 0x00000001903149a0 NSKeyValueDidChangeWithPerThreadPendingNotifications + 160 15 AppKit 0x00000001924673d4 -[NSThemeFrame _didChangeContentLayoutRect] + 76 16 AppKit 0x000000019246521c -[NSWindow _oldPlaceWindow:fromServer:] + 744 ) It seems like the system attempts to access a screen object that is already nil after the external monitor is removed. This leads to an assertion failure in UINSWorkspace. Is there any known workaround or update planned to address this issue? Thank you.
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257
May ’25
SwiftUI List - onInsert not called on iOS (works on macOS)
I am working with a simple SwiftUI List and I want to enable functionality that allows files and images to be dropped onto the List from outside the app. There is an onInsert modifier with List that allows for this, but I found that it works on macOS, but not when running the same view on iOS. I have sample code that I can't seem to post on this forum because it keeps giving me a validation error about "This post contains sensitive language". Maybe this will work: Code to reproduce issue Is there anything I can do to make this work on iOS?
1
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119
May ’25
visionOS NavigationSplitView - Refreshable ProgressView Disappears
Description I've encountered an issue with NavigationSplitView on visionOS when using a refreshable ScrollView or List in the detail view. The Problem: When implementing pull-to-refresh in the detail view of a NavigationSplitView, the ProgressView disappears and generates this warning: Trying to convert coordinates between views that are in different UIWindows, which isn't supported. Use convertPoint:fromCoordinateSpace: instead. I discovered that if the detail view includes a .navigationTitle(), the ProgressView remains visible and works correctly! Below is a minimal reproducible example showing this behavior. When you run this code, you'll notice: The sidebar refreshable works fine The detail refreshable works only when .navigationTitle("Something") is present Remove the navigationTitle and the detail view's refresh indicator disappears minimal Demo import SwiftUI struct MinimalRefreshableDemo: View { @State private var items = ["Item 1", "Item 2", "Item 3"] @State private var detailItems = ["Detail 1", "Detail 2", "Detail 3"] @State private var selectedItem: String? = "Item 1" var body: some View { NavigationSplitView { List(items, id: \.self, selection: $selectedItem) { item in Text(item) } .refreshable { items = ["Item 1", "Item 2", "Item 3"] } .navigationTitle("Chat") } detail: { List { ForEach(detailItems, id: \.self) { item in Text(item) .frame(height: 100) .frame(maxWidth: .infinity) } } .refreshable { detailItems = ["Detail 1", "Detail 2", "Detail 3"] } .navigationTitle("Something") } } } #Preview { MinimalRefreshableDemo() } Is this expected behavior? Has anyone else encountered this issue or found a solution that doesn't require adding a navigation title?
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102
May ’25
CollectionViewCell switch back to single column once UImage is assigned
Hi I am building a simple multi column CollectionView here and trying to add 3 cell in a row. Well, in short the column and rows looks all fine if I comment the below code. which is no image and text assigned to cells. let framework = list[indexPath.item] cell.configure(framework) However, once uncommented, only a single cell is displayed per row and the image doesn't seem to be resizing automatically. Can you please advise. Below is the ViewController. import UIKit class FrameworkListViewController: UIViewController { @IBOutlet weak var collectionView: UICollectionView! let list: [AppleFramework] = AppleFramework.list override func viewDidLoad() { super.viewDidLoad() collectionView.dataSource = self collectionView.delegate = self } } extension FrameworkListViewController: UICollectionViewDataSource { func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return list.count } func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "FrameworkCell", for: indexPath) as? FrameworkCell else { return UICollectionViewCell() } let framework = list[indexPath.item] cell.configure(framework) return cell } } extension FrameworkListViewController: UICollectionViewDelegateFlowLayout { func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize { let interItemSpacing: CGFloat = 10 let width = (collectionView.bounds.width - interItemSpacing * 2) / 3 let height = width * 1.5 return CGSize(width: width, height: height) } func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat { return 10 } func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat { return 10 } } This is Cell class FrameworkCell: UICollectionViewCell { @IBOutlet weak var thumbnailImageView: UIImageView! @IBOutlet weak var nameLabel: UILabel! func configure(_ framework: AppleFramework) { thumbnailImageView.image = UIImage(named: framework.imageName) nameLabel.text = framework.name } }
Topic: UI Frameworks SubTopic: UIKit
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77
May ’25
tvOS: Using .onExitCommand to Navigate to Home Tab Before Exiting — Is This Acceptable?
Hi Apple Developer Team, In my tvOS app built with SwiftUI, I have a tab-based interface with several sections. The first tab (index 0) is the Home tab. Other tabs include Contact, WiFi, Welcome, etc. I want to handle the remote's Menu / Back button (.onExitCommand) so that: If the user is on any tab other than Home (tabs 1, 2, 3, etc.), pressing the Menu button takes them back to the Home tab. If the user is already on the Home tab, then pressing the TV/Home button (not Menu) behaves as expected — suspending or exiting the app (handled by the system, no code involved). Here's a simplified version of what I implemented: .onExitCommand { if selectedTab != 0 { selectedTab = 0 focusedTab = 0 } else { // Let system handle the exit when user presses the TV/Home button } } This behavior ensures users don’t accidentally exit the app when they're browsing other tabs, and provides a consistent navigation experience. Question: Is this an acceptable and App Store-compliant use of .onExitCommand on tvOS? I'm not calling exit(0) or trying to force-terminate the app — just using .onExitCommand for in-app navigation purposes. Any official guidance or best practices would be greatly appreciated! Thanks, Prashant
Topic: UI Frameworks SubTopic: SwiftUI Tags:
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122
May ’25
Does adding a bar button item to the navigation bar programmatically when offering scene support differ from the old app delegate approach
I have used the following code for years to add a right bar button item to the navigation bar, but for some unknown reason, this no longer works. It stopped working when I updated my app to have Scene support. I don't understand what is preventing this code from working. @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. NSLog(@"viewDidLoad"); // Add a Share Button UIBarButtonItem *shareButton; shareButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self action:@selector(editProject:)]; self.navigationItem.rightBarButtonItem = shareButton; self.navigationItem.rightBarButtonItem.tintColor = [UIColor blueColor]; } -(void) editProject:(id)sender { } @end To test this, I created a brand new test app that does nothing except for attempting to add this button. The autogenerated code gives you the following project and I simply modified the ViewController class as shown above: What do I need to do differently to make the right bar button item to display? I know that I can add buttons using the storyboard that can be controlled via IBOutlets, but just want to know if its still possible to do this programmatically.
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172
May ’25
Crash due to likely infinitely recursive call in SwiftUI `Color.Resolved.init`
So I'm dealing with a really obtuse crash that appears to be a stack overflow in an internal SwiftUI code path creating a Color.Resolved. I haven't found anyone one else with this issue online, and I cannot get it to reproduce on my own device. Interestingly enough, it is only happening on 1 device in the field (according to XCode crash logs). Here are some lines from the crashed thread. You can see that my code is never called, and it appears to be starting in some Array equality check checking the equality of colors (which I can't think of anywhere in my app I am doing anyway). You can see from this trace here that it appears to be a recursive call through Color.Resolved and NSColor.withColorAppearance. I don't have any idea how to solve this, but it keeps happening with at least one in-the-field device across multiple app updates. So my whole app is open source on github at https://github.com/msdrigg/roam, but I don't even use NSColor explicitly anywhere except for here which doesn't match the stack trace. I also tried changing the accent color of the app with defaults write com.msdrigg.roam AppleAccentColor -integer 1 to see if that somehow caused the crash, but my app opened up totally fine (and respected the change). Besides this, the only places I think I could be using dynamic colors is I when define an AccentColor and a WidgetBackground color for my app using xcassets, and then I use these colors from SwiftUI. In most of my app I stick to the system colors (Color.gray and such). Thread 0 Crashed: 0 libsystem_pthread.dylib 0x000000018601213c ___chkstk_darwin + 60 1 CoreFoundation 0x0000000186108434 -[NSArray isEqualToArray:] + 52 (NSArray.m:454) 2 AppKit 0x000000018a21fcd4 -[NSCoreUICatalogColor resolvedCUINamedColorForAppearance:] + 164 (NSColor.m:5057) 3 AppKit 0x0000000189c32cd4 -[NSCoreUICatalogColor resolvedColor] + 48 (NSColor.m:5148) 4 AppKit 0x0000000189c31e74 -[NSDynamicNamedColor colorUsingColorSpace:] + 32 (NSColor.m:4410) 5 SwiftUICore 0x0000000221ca9fd8 CoreColorPlatformColorGetComponents + 116 (CoreColorFunctions.m:149) 6 SwiftUICore 0x0000000221faaf28 specialized Color.Resolved.init(platformColor:) + 92 (CoreColor.swift:14) 7 SwiftUICore 0x0000000221faa5b0 Color.Resolved.init(platformColor:) + 16 (<compiler-generated>:0) 8 SwiftUI 0x00000001b53b1dc4 closure #1 in NSColor.resolve(in:) + 20 (AppKitColorConversions.swift:156) 9 SwiftUI 0x00000001b53b222c partial apply for closure #1 in static NSColor.withColorAppearance(in:_:) + 32 (<compiler-generated>:0) 10 SwiftUI 0x00000001b46b1e54 closure #1 in SubmitTriggerSource.dispatchUpdate(_:) + 28 (PlatformViewCoordinator.swift:12) 11 SwiftUI 0x00000001b5484488 thunk for @escaping @callee_guaranteed () -> () + 28 (<compiler-generated>:0) 12 AppKit 0x0000000189c174a4 +[NSAppearance _performWithCurrentAppearance:usingBlock:] + 72 (NSAppearance.m:2408) 13 SwiftUI 0x00000001b53b2088 specialized static NSColor.withColorAppearance(in:_:) + 324 (AppKitColorConversions.swift:142) 14 SwiftUI 0x00000001b53b1e7c protocol witness for ColorProvider.resolve(in:) in conformance NSColor + 68 (<compiler-generated>:151) 15 SwiftUICore 0x0000000222436e6c ColorBox.resolve(in:) + 124 (Color.swift:288) 16 SwiftUICore 0x0000000222435e30 Color.resolve(in:) + 72 (Color.swift:87) 17 SwiftUI 0x00000001b53b1c88 closure #1 in NSColor.init(_:) + 196 (AppKitColorConversions.swift:124) 18 SwiftUI 0x00000001b4542714 thunk for @escaping @callee_guaranteed (@guaranteed NSAppearance) -> (@owned NSColor) + 56 (<compiler-generated>:0) 19 AppKit 0x0000000189c31e74 -[NSDynamicNamedColor colorUsingColorSpace:] + 32 (NSColor.m:4410) //// ... Repeating for 500 lines 500 SwiftUICore 0x0000000221ca9fd8 CoreColorPlatformColorGetComponents + 116 (CoreColorFunctions.m:149) 501 SwiftUICore 0x0000000221faaf28 specialized Color.Resolved.init(platformColor:) + 92 (CoreColor.swift:14) 502 SwiftUICore 0x0000000221faa5b0 Color.Resolved.init(platformColor:) + 16 (<compiler-generated>:0) 503 SwiftUI 0x00000001b53b1dc4 closure #1 in NSColor.resolve(in:) + 20 (AppKitColorConversions.swift:156) 504 SwiftUI 0x00000001b53b222c partial apply for closure #1 in static NSColor.withColorAppearance(in:_:) + 32 (<compiler-generated>:0) 505 SwiftUI 0x00000001b46b1e54 closure #1 in SubmitTriggerSource.dispatchUpdate(_:) + 28 (PlatformViewCoordinator.swift:12) 506 SwiftUI 0x00000001b5484488 thunk for @escaping @callee_guaranteed () -> () + 28 (<compiler-generated>:0) 507 AppKit 0x0000000189c174a4 +[NSAppearance _performWithCurrentAppearance:usingBlock:] + 72 (NSAppearance.m:2408) 508 SwiftUI 0x00000001b53b2088 specialized static NSColor.withColorAppearance(in:_:) + 324 (AppKitColorConversions.swift:142) 509 SwiftUI 0x00000001b53b1e7c protocol witness for ColorProvider.resolve(in:) in conformance NSColor + 68 (<compiler-generated>:151) 510 SwiftUICore 0x0000000222436e6c ColorBox.resolve(in:) + 124 (Color.swift:288) full-log.crash
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146
May ’25
Mixing ReferenceFileDocument and @Observable
I have an app in which the data model is @Observable, and views see it through @Environment(dataModel.self) private var dataModel. Since there are a large number of views, only some of which may need to be redrawn at a given time, I believe that @Observable is more efficient at run time than @Published and @ObservedObject I’ve been trying to make the app document based. Although I started using SwiftData, it has trouble with Codable, and a long thread in the Developer forum suggests that SwiftData does not support the Undo manager - and in any event, simple JSON serialization is all that this app requires. Unfortunately, ReferenceFileDocument inherits from ObservableObject, which seems to not play nice with @Observable. I’d like to keep using @Observable, but haven’t been able to figure out how. When I deserialize a JSON ReferenceFileDocument, I can’t seem to connect it to an @Observable class instance and to let the various views and view models know where to find and update it. I’d appreciate advice on how to implement document persistence in this app. Also, the default behaviour of DoumentGroup provides a nice menu to, another things, rename a new file to something other than Untitled xx, but it doesn’t appear to work (there is an extensive thread on the Developer website discussing this issue). Is there a solution to this problem? Thanks for any help you can offer.
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177
May ’25
onDrop() modifier with multiple UTTypes giving the least helpful one?
Hey folks I'm trying to use .onDrop() on a view that needs to accept files. This works fine, I specify a supportedContentTypes of [.fileURL] and it works great. I got a request to add support for dragging the macOS screenshot previews into my app and when I looked at it, they aren't available as a URL, only an image, so I changed my array to [.fileURL, .image]. As soon as I did that, I noticed that dragging any image file, even from Finder, calls my onDrop() closure with an NSItemProvider that only knows how to give me an image, with no suggestedName. Am I missing something here? I had been under the impression that: The order of my supportedContentTypes indicates which types I prefer (although I now can't find this documented anywhere) Where an item could potentially vend multiple UTTypes, the resulting NSItemProvider would offer up the union of types that both it, and I, support. If it helps, I put together a little test app which lets you select which UTTypes are in supportedContentTypes and then when a file is dragged onto it, it'll tell you which content types are available - as far as I can tell, it's only ever one, and macOS strongly prefers to send me an image vs a URL. Is there anything I can do to convince it otherwise?
4
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225
May ’25
UIPageViewController embedded in UIScrollView ignores the first pan gesture on its pages
I have a UIPageViewController embedded in a UIScrollView and each page has a drawing view with a UIPanGestureRecognizer to free-draw. With this setup, the 1st time I attempt to draw, the pan gesture is ignored. It works the 2nd time I perform the gesture. In my case I need to wrap the UIPageViewController in a UIScrollView to have a pull to refresh mechanism (set thescrollView.refreshControl). I’ve tried every combination of UIGestureRecognizerDelegate methods (shouldRecognizeSimultaneously…, require(toFail:), etc.) with no luck. This is my view hierarchy: ScrollView |- UIPageViewController |- Page 1 | |- DrawingView with UIPanGestureRecognizer |- Page 2 |- DrawingView with UIPanGestureRecognizer Is this a known limitation when a UIPageViewController is nested inside another scroll view? Reproduction steps (tested on iOS 18.4 / Xcode 16.3, iPhone 16 Pro) Launch the app; the first page shows a white canvas in the bottom part. Try to draw immediately → nothing happens. Lift your finger and draw again → works. Here is a link for the sample project with the reproducible code: https://github.com/marcod-storyteller/page-controller-sample P.S: If the UIPageViewController has a .pageCurl transition style instead, the problem disappears.
Topic: UI Frameworks SubTopic: UIKit Tags:
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126
May ’25
The URL authorization read and write obtained by UIDocumentPickerViewController
The URL directory obtained by UIDocumentPickerVieweController can be read and written in the directory after calling startAccessingDecurityScopeResource. However, after restarting the app, if the URL saved in the package is called startAccessingDecurityScopeResource again and returns NO, UIDocumentPickerVieweController must be called again to retrieve the URL, and then startAccessingDecurityScopeResource must be called again before continuing the operation. This is too troublesome. Is there a way to continue reading and writing operations in the URL directory after restarting the app?
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84
May ’25
SwiftData/ModelSnapshot.swift:46: Fatal error: A ModelSnapshot must be initialized with a known-keys dictionary
I'm running into a crash when trying to delete an item from a list that's loaded using SwiftData. The app works fine when selecting or displaying the data, but the moment I confirm a deletion, it crashes with this error: SwiftData/ModelSnapshot.swift:46: Fatal error: A ModelSnapshot must be initialized with a known-keys dictionary This happens right after I delete an item from the list using modelContext.delete(). I’ve double-checked that the item exists and is valid, and I'm not sure what I'm doing wrong. The data is loaded using @Query and everything seems normal until deletion. For further information, I have tried this on a new IOS project where I have one super Model class with a cascading relationship on a child class. When trying to delete the parent class while connected to one or more children, it still gives me the error. The same thing is happening with my original project. Class A has a relationship (cascading) with Class B. Attempting to delete Class A while there are relationships with Class B throws this error. If anyone has experienced this or knows what causes it, please let me know. I’m not even sure where to start debugging this one. Thanks in advance!
Replies
2
Boosts
1
Views
245
Activity
May ’25
ScreenBlur is not happening always when app goes to app switcher.
We have written code to blur the app screen in "applicationWillResignActive" when app goes to app switcher. But the blur affect is observed only some times. Is there is any specific reason for this? We have a doubt that applicationWillResignActive is not always completely executed or is dismissed by OS for other priority activities. Is this is expected behaviour or are we missing anything here?
Topic: UI Frameworks SubTopic: UIKit
Replies
13
Boosts
0
Views
302
Activity
May ’25
Regarding ARKit camera feed zoom and macro support for closer object
I am currently developing an AR experience using ARKit with SceneKit and am looking to implement functionality that enables: Zooming into the AR camera feed, ideally leveraging the ultra-wide or telephoto lenses available on supported devices. Macro-style focus capabilities, allowing users to view and interact with virtual content closely aligned with small or nearby real-world objects (within a few centimeters). My objective is to ensure that ARKit continues to render the scene accurately while enabling a zoomed-in view or macro-level focus for better detail visibility and alignment. Could you please advise on: Whether ARKit currently supports camera zoom or allows access to macro or ultra-wide cameras within an ARSession. Limitations or considerations when using multi-camera setups in conjunction with ARKit. Any guidance or references to documentation or sample code would be greatly appreciated. Best regards, Ayush
Replies
0
Boosts
0
Views
191
Activity
May ’25
ARKit Camera Feed Zoom & Macro Support for Close-Range Objects
I am currently developing an AR experience using ARKit with SceneKit and am looking to implement functionality that enables: Zooming into the AR camera feed, ideally leveraging the ultra-wide or telephoto lenses available on supported devices. Macro-style focus capabilities, allowing users to view and interact with virtual content closely aligned with small or nearby real-world objects (within a few centimeters). My objective is to ensure that ARKit continues to render the scene accurately while enabling a zoomed-in view or macro-level focus for better detail visibility and alignment. Could you please advise on: Whether ARKit currently supports camera zoom or allows access to macro or ultra-wide cameras within an ARSession. Limitations or considerations when using multi-camera setups in conjunction with ARKit. Any guidance or references to documentation or sample code would be greatly appreciated.
Replies
0
Boosts
0
Views
238
Activity
May ’25
Room Plan Issue (structure.capturedStructure)
Hi everyone, My app crashed when using the merge room feature. I suspect the issue might be caused by a wall having more than 4 edges. Has anyone experienced a similar problem and found a solution? I’d really appreciate any advice or suggestions. Thank you all, and have a great day! let capturedStructure = try await structure.capturedStructure(from: self.rooms)
Replies
2
Boosts
1
Views
278
Activity
May ’25
[StoreKit] Runtime warning with manageSubscriptionsSheet and ObservableObject
The following runtime warning is emitted by Xcode when using the manageSubscriptionsSheet with an ObservableObject: \ContentViewModel.isPresented is isolated to the main actor. Accessing it via Binding from a different actor will cause undefined behaviors, and potential data races; This warning will become a runtime crash in a future version of SwiftUI. Publishing changes from background threads is not allowed; make sure to publish values from the main thread (via operators like receive(on:)) on model updates. This minimal sample project reproduces the issue: class ContentViewModel: ObservableObject { @Published var isPresented = false func didTapButton() { self.isPresented = true } } struct ContentView: View { @ObservedObject var viewModel: ContentViewModel var body: some View { Button("Tap me") { self.viewModel.didTapButton() } .manageSubscriptionsSheet(isPresented: self.$viewModel.isPresented) } } Reproduced on: Xcode 16.2 Xcode 16.3 beta both with a simulator and a real device. This doesn't happen when using @Observable.
Replies
1
Boosts
1
Views
288
Activity
May ’25
Deadline for Adopting Scene-Based Life-Cycle in UIKit Apps
I found the following statement on the site https://developer.apple.com/documentation/technotes/tn3187-migrating-to-the-uikit-scene-based-life-cycle: "Soon, all UIKit based apps will be required to adopt the scene-based life-cycle, after which your app won’t launch if you don’t. While supporting multiple scenes is encouraged, only adoption of scene life-cycle is required." Could you please clarify when exactly apps will no longer be able to launch if they do not adopt the scene-based life-cycle? I would like to confirm the deadline as the impact of this change is significant.
Topic: UI Frameworks SubTopic: UIKit Tags:
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328
Activity
May ’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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134
Activity
May ’25
Crash when minimizing on external display and unplugging it (iOS App on Mac)
Our iOS app, when running as an iOS App on Mac, crashes consistently under the following scenario: 1. Launch the app on an external display. 2. Minimize the app window. 3. Disconnect the external display. The app crashes every time under these conditions. The crash log shows the following call stack: *** Assertion failure in -[UINSWorkspace _maximumContentSizeForWindowOnScreen:], UINSWorkspace.m:401 -[UINSWorkspace _maximumContentSizeForWindowOnScreen:]: screen parameter should not be nil ( 0 CoreFoundation 0x000000018e841df0 __exceptionPreprocess + 176 1 libobjc.A.dylib 0x000000018e306b60 objc_exception_throw + 88 2 Foundation 0x000000018fb6aa78 -[NSCalendarDate initWithCoder:] + 0 3 UIKitMacHelper 0x00000001a9a59110 -[UINSWorkspace _maximumContentSizeForWindowOnScreen:] + 184 4 UIKitMacHelper 0x00000001a9a3e748 -[UINSSceneViewController _usableScreenSizeWithSceneSize:shouldOverride:] + 412 5 UIKitMacHelper 0x00000001a9a3d55c -[UINSSceneViewController _effectiveScaleFactorForLayoutWithOverride:] + 88 6 UIKitMacHelper 0x00000001a9a3f3a8 -[UINSSceneViewController _updateZoomFactors] + 28 7 UIKitMacHelper 0x00000001a9a3f248 -[UINSSceneViewController _updateZoomFactorsAndDoLayout] + 24 8 UIKitMacHelper 0x00000001a9a3df80 -[UINSSceneViewController _doUpdates:] + 104 9 UIKitMacHelper 0x00000001a99ad460 -[UINSSceneViewController observeValueForKeyPath:ofObject:change:context:] + 176 10 Foundation 0x000000018facb0d8 -[NSKeyValueObservance observeValueForKeyPath:ofObject:change:context:] + 388 11 Foundation 0x000000018facb0d8 -[NSKeyValueObservance observeValueForKeyPath:ofObject:change:context:] + 388 12 Foundation 0x000000018fa8f7b4 NSKeyValueNotifyObserver + 252 13 Foundation 0x000000018fb3c560 NSKeyValueDidChange + 388 14 Foundation 0x00000001903149a0 NSKeyValueDidChangeWithPerThreadPendingNotifications + 160 15 AppKit 0x00000001924673d4 -[NSThemeFrame _didChangeContentLayoutRect] + 76 16 AppKit 0x000000019246521c -[NSWindow _oldPlaceWindow:fromServer:] + 744 ) It seems like the system attempts to access a screen object that is already nil after the external monitor is removed. This leads to an assertion failure in UINSWorkspace. Is there any known workaround or update planned to address this issue? Thank you.
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257
Activity
May ’25
SwiftUI List - onInsert not called on iOS (works on macOS)
I am working with a simple SwiftUI List and I want to enable functionality that allows files and images to be dropped onto the List from outside the app. There is an onInsert modifier with List that allows for this, but I found that it works on macOS, but not when running the same view on iOS. I have sample code that I can't seem to post on this forum because it keeps giving me a validation error about "This post contains sensitive language". Maybe this will work: Code to reproduce issue Is there anything I can do to make this work on iOS?
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119
Activity
May ’25
visionOS NavigationSplitView - Refreshable ProgressView Disappears
Description I've encountered an issue with NavigationSplitView on visionOS when using a refreshable ScrollView or List in the detail view. The Problem: When implementing pull-to-refresh in the detail view of a NavigationSplitView, the ProgressView disappears and generates this warning: Trying to convert coordinates between views that are in different UIWindows, which isn't supported. Use convertPoint:fromCoordinateSpace: instead. I discovered that if the detail view includes a .navigationTitle(), the ProgressView remains visible and works correctly! Below is a minimal reproducible example showing this behavior. When you run this code, you'll notice: The sidebar refreshable works fine The detail refreshable works only when .navigationTitle("Something") is present Remove the navigationTitle and the detail view's refresh indicator disappears minimal Demo import SwiftUI struct MinimalRefreshableDemo: View { @State private var items = ["Item 1", "Item 2", "Item 3"] @State private var detailItems = ["Detail 1", "Detail 2", "Detail 3"] @State private var selectedItem: String? = "Item 1" var body: some View { NavigationSplitView { List(items, id: \.self, selection: $selectedItem) { item in Text(item) } .refreshable { items = ["Item 1", "Item 2", "Item 3"] } .navigationTitle("Chat") } detail: { List { ForEach(detailItems, id: \.self) { item in Text(item) .frame(height: 100) .frame(maxWidth: .infinity) } } .refreshable { detailItems = ["Detail 1", "Detail 2", "Detail 3"] } .navigationTitle("Something") } } } #Preview { MinimalRefreshableDemo() } Is this expected behavior? Has anyone else encountered this issue or found a solution that doesn't require adding a navigation title?
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102
Activity
May ’25
CollectionViewCell switch back to single column once UImage is assigned
Hi I am building a simple multi column CollectionView here and trying to add 3 cell in a row. Well, in short the column and rows looks all fine if I comment the below code. which is no image and text assigned to cells. let framework = list[indexPath.item] cell.configure(framework) However, once uncommented, only a single cell is displayed per row and the image doesn't seem to be resizing automatically. Can you please advise. Below is the ViewController. import UIKit class FrameworkListViewController: UIViewController { @IBOutlet weak var collectionView: UICollectionView! let list: [AppleFramework] = AppleFramework.list override func viewDidLoad() { super.viewDidLoad() collectionView.dataSource = self collectionView.delegate = self } } extension FrameworkListViewController: UICollectionViewDataSource { func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return list.count } func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "FrameworkCell", for: indexPath) as? FrameworkCell else { return UICollectionViewCell() } let framework = list[indexPath.item] cell.configure(framework) return cell } } extension FrameworkListViewController: UICollectionViewDelegateFlowLayout { func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize { let interItemSpacing: CGFloat = 10 let width = (collectionView.bounds.width - interItemSpacing * 2) / 3 let height = width * 1.5 return CGSize(width: width, height: height) } func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat { return 10 } func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat { return 10 } } This is Cell class FrameworkCell: UICollectionViewCell { @IBOutlet weak var thumbnailImageView: UIImageView! @IBOutlet weak var nameLabel: UILabel! func configure(_ framework: AppleFramework) { thumbnailImageView.image = UIImage(named: framework.imageName) nameLabel.text = framework.name } }
Topic: UI Frameworks SubTopic: UIKit
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77
Activity
May ’25
tvOS: Using .onExitCommand to Navigate to Home Tab Before Exiting — Is This Acceptable?
Hi Apple Developer Team, In my tvOS app built with SwiftUI, I have a tab-based interface with several sections. The first tab (index 0) is the Home tab. Other tabs include Contact, WiFi, Welcome, etc. I want to handle the remote's Menu / Back button (.onExitCommand) so that: If the user is on any tab other than Home (tabs 1, 2, 3, etc.), pressing the Menu button takes them back to the Home tab. If the user is already on the Home tab, then pressing the TV/Home button (not Menu) behaves as expected — suspending or exiting the app (handled by the system, no code involved). Here's a simplified version of what I implemented: .onExitCommand { if selectedTab != 0 { selectedTab = 0 focusedTab = 0 } else { // Let system handle the exit when user presses the TV/Home button } } This behavior ensures users don’t accidentally exit the app when they're browsing other tabs, and provides a consistent navigation experience. Question: Is this an acceptable and App Store-compliant use of .onExitCommand on tvOS? I'm not calling exit(0) or trying to force-terminate the app — just using .onExitCommand for in-app navigation purposes. Any official guidance or best practices would be greatly appreciated! Thanks, Prashant
Topic: UI Frameworks SubTopic: SwiftUI Tags:
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122
Activity
May ’25
CarPlay and iOS 18.5, app crashes if the mobile one is not running
Hi, after upgrading to iOS 18.5 our app crashes in CarPlay. Only when the app is running on our mobile the carplay app works fine. If we run the same app in mobiles with iOS < 18.5 everything works. What has changed in iOS 18.5? Thanks
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114
Activity
May ’25
Does adding a bar button item to the navigation bar programmatically when offering scene support differ from the old app delegate approach
I have used the following code for years to add a right bar button item to the navigation bar, but for some unknown reason, this no longer works. It stopped working when I updated my app to have Scene support. I don't understand what is preventing this code from working. @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. NSLog(@"viewDidLoad"); // Add a Share Button UIBarButtonItem *shareButton; shareButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self action:@selector(editProject:)]; self.navigationItem.rightBarButtonItem = shareButton; self.navigationItem.rightBarButtonItem.tintColor = [UIColor blueColor]; } -(void) editProject:(id)sender { } @end To test this, I created a brand new test app that does nothing except for attempting to add this button. The autogenerated code gives you the following project and I simply modified the ViewController class as shown above: What do I need to do differently to make the right bar button item to display? I know that I can add buttons using the storyboard that can be controlled via IBOutlets, but just want to know if its still possible to do this programmatically.
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3
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172
Activity
May ’25
Crash due to likely infinitely recursive call in SwiftUI `Color.Resolved.init`
So I'm dealing with a really obtuse crash that appears to be a stack overflow in an internal SwiftUI code path creating a Color.Resolved. I haven't found anyone one else with this issue online, and I cannot get it to reproduce on my own device. Interestingly enough, it is only happening on 1 device in the field (according to XCode crash logs). Here are some lines from the crashed thread. You can see that my code is never called, and it appears to be starting in some Array equality check checking the equality of colors (which I can't think of anywhere in my app I am doing anyway). You can see from this trace here that it appears to be a recursive call through Color.Resolved and NSColor.withColorAppearance. I don't have any idea how to solve this, but it keeps happening with at least one in-the-field device across multiple app updates. So my whole app is open source on github at https://github.com/msdrigg/roam, but I don't even use NSColor explicitly anywhere except for here which doesn't match the stack trace. I also tried changing the accent color of the app with defaults write com.msdrigg.roam AppleAccentColor -integer 1 to see if that somehow caused the crash, but my app opened up totally fine (and respected the change). Besides this, the only places I think I could be using dynamic colors is I when define an AccentColor and a WidgetBackground color for my app using xcassets, and then I use these colors from SwiftUI. In most of my app I stick to the system colors (Color.gray and such). Thread 0 Crashed: 0 libsystem_pthread.dylib 0x000000018601213c ___chkstk_darwin + 60 1 CoreFoundation 0x0000000186108434 -[NSArray isEqualToArray:] + 52 (NSArray.m:454) 2 AppKit 0x000000018a21fcd4 -[NSCoreUICatalogColor resolvedCUINamedColorForAppearance:] + 164 (NSColor.m:5057) 3 AppKit 0x0000000189c32cd4 -[NSCoreUICatalogColor resolvedColor] + 48 (NSColor.m:5148) 4 AppKit 0x0000000189c31e74 -[NSDynamicNamedColor colorUsingColorSpace:] + 32 (NSColor.m:4410) 5 SwiftUICore 0x0000000221ca9fd8 CoreColorPlatformColorGetComponents + 116 (CoreColorFunctions.m:149) 6 SwiftUICore 0x0000000221faaf28 specialized Color.Resolved.init(platformColor:) + 92 (CoreColor.swift:14) 7 SwiftUICore 0x0000000221faa5b0 Color.Resolved.init(platformColor:) + 16 (<compiler-generated>:0) 8 SwiftUI 0x00000001b53b1dc4 closure #1 in NSColor.resolve(in:) + 20 (AppKitColorConversions.swift:156) 9 SwiftUI 0x00000001b53b222c partial apply for closure #1 in static NSColor.withColorAppearance(in:_:) + 32 (<compiler-generated>:0) 10 SwiftUI 0x00000001b46b1e54 closure #1 in SubmitTriggerSource.dispatchUpdate(_:) + 28 (PlatformViewCoordinator.swift:12) 11 SwiftUI 0x00000001b5484488 thunk for @escaping @callee_guaranteed () -> () + 28 (<compiler-generated>:0) 12 AppKit 0x0000000189c174a4 +[NSAppearance _performWithCurrentAppearance:usingBlock:] + 72 (NSAppearance.m:2408) 13 SwiftUI 0x00000001b53b2088 specialized static NSColor.withColorAppearance(in:_:) + 324 (AppKitColorConversions.swift:142) 14 SwiftUI 0x00000001b53b1e7c protocol witness for ColorProvider.resolve(in:) in conformance NSColor + 68 (<compiler-generated>:151) 15 SwiftUICore 0x0000000222436e6c ColorBox.resolve(in:) + 124 (Color.swift:288) 16 SwiftUICore 0x0000000222435e30 Color.resolve(in:) + 72 (Color.swift:87) 17 SwiftUI 0x00000001b53b1c88 closure #1 in NSColor.init(_:) + 196 (AppKitColorConversions.swift:124) 18 SwiftUI 0x00000001b4542714 thunk for @escaping @callee_guaranteed (@guaranteed NSAppearance) -> (@owned NSColor) + 56 (<compiler-generated>:0) 19 AppKit 0x0000000189c31e74 -[NSDynamicNamedColor colorUsingColorSpace:] + 32 (NSColor.m:4410) //// ... Repeating for 500 lines 500 SwiftUICore 0x0000000221ca9fd8 CoreColorPlatformColorGetComponents + 116 (CoreColorFunctions.m:149) 501 SwiftUICore 0x0000000221faaf28 specialized Color.Resolved.init(platformColor:) + 92 (CoreColor.swift:14) 502 SwiftUICore 0x0000000221faa5b0 Color.Resolved.init(platformColor:) + 16 (<compiler-generated>:0) 503 SwiftUI 0x00000001b53b1dc4 closure #1 in NSColor.resolve(in:) + 20 (AppKitColorConversions.swift:156) 504 SwiftUI 0x00000001b53b222c partial apply for closure #1 in static NSColor.withColorAppearance(in:_:) + 32 (<compiler-generated>:0) 505 SwiftUI 0x00000001b46b1e54 closure #1 in SubmitTriggerSource.dispatchUpdate(_:) + 28 (PlatformViewCoordinator.swift:12) 506 SwiftUI 0x00000001b5484488 thunk for @escaping @callee_guaranteed () -> () + 28 (<compiler-generated>:0) 507 AppKit 0x0000000189c174a4 +[NSAppearance _performWithCurrentAppearance:usingBlock:] + 72 (NSAppearance.m:2408) 508 SwiftUI 0x00000001b53b2088 specialized static NSColor.withColorAppearance(in:_:) + 324 (AppKitColorConversions.swift:142) 509 SwiftUI 0x00000001b53b1e7c protocol witness for ColorProvider.resolve(in:) in conformance NSColor + 68 (<compiler-generated>:151) 510 SwiftUICore 0x0000000222436e6c ColorBox.resolve(in:) + 124 (Color.swift:288) full-log.crash
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146
Activity
May ’25
Mixing ReferenceFileDocument and @Observable
I have an app in which the data model is @Observable, and views see it through @Environment(dataModel.self) private var dataModel. Since there are a large number of views, only some of which may need to be redrawn at a given time, I believe that @Observable is more efficient at run time than @Published and @ObservedObject I’ve been trying to make the app document based. Although I started using SwiftData, it has trouble with Codable, and a long thread in the Developer forum suggests that SwiftData does not support the Undo manager - and in any event, simple JSON serialization is all that this app requires. Unfortunately, ReferenceFileDocument inherits from ObservableObject, which seems to not play nice with @Observable. I’d like to keep using @Observable, but haven’t been able to figure out how. When I deserialize a JSON ReferenceFileDocument, I can’t seem to connect it to an @Observable class instance and to let the various views and view models know where to find and update it. I’d appreciate advice on how to implement document persistence in this app. Also, the default behaviour of DoumentGroup provides a nice menu to, another things, rename a new file to something other than Untitled xx, but it doesn’t appear to work (there is an extensive thread on the Developer website discussing this issue). Is there a solution to this problem? Thanks for any help you can offer.
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3
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177
Activity
May ’25
onDrop() modifier with multiple UTTypes giving the least helpful one?
Hey folks I'm trying to use .onDrop() on a view that needs to accept files. This works fine, I specify a supportedContentTypes of [.fileURL] and it works great. I got a request to add support for dragging the macOS screenshot previews into my app and when I looked at it, they aren't available as a URL, only an image, so I changed my array to [.fileURL, .image]. As soon as I did that, I noticed that dragging any image file, even from Finder, calls my onDrop() closure with an NSItemProvider that only knows how to give me an image, with no suggestedName. Am I missing something here? I had been under the impression that: The order of my supportedContentTypes indicates which types I prefer (although I now can't find this documented anywhere) Where an item could potentially vend multiple UTTypes, the resulting NSItemProvider would offer up the union of types that both it, and I, support. If it helps, I put together a little test app which lets you select which UTTypes are in supportedContentTypes and then when a file is dragged onto it, it'll tell you which content types are available - as far as I can tell, it's only ever one, and macOS strongly prefers to send me an image vs a URL. Is there anything I can do to convince it otherwise?
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4
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225
Activity
May ’25
UIPageViewController embedded in UIScrollView ignores the first pan gesture on its pages
I have a UIPageViewController embedded in a UIScrollView and each page has a drawing view with a UIPanGestureRecognizer to free-draw. With this setup, the 1st time I attempt to draw, the pan gesture is ignored. It works the 2nd time I perform the gesture. In my case I need to wrap the UIPageViewController in a UIScrollView to have a pull to refresh mechanism (set thescrollView.refreshControl). I’ve tried every combination of UIGestureRecognizerDelegate methods (shouldRecognizeSimultaneously…, require(toFail:), etc.) with no luck. This is my view hierarchy: ScrollView |- UIPageViewController |- Page 1 | |- DrawingView with UIPanGestureRecognizer |- Page 2 |- DrawingView with UIPanGestureRecognizer Is this a known limitation when a UIPageViewController is nested inside another scroll view? Reproduction steps (tested on iOS 18.4 / Xcode 16.3, iPhone 16 Pro) Launch the app; the first page shows a white canvas in the bottom part. Try to draw immediately → nothing happens. Lift your finger and draw again → works. Here is a link for the sample project with the reproducible code: https://github.com/marcod-storyteller/page-controller-sample P.S: If the UIPageViewController has a .pageCurl transition style instead, the problem disappears.
Topic: UI Frameworks SubTopic: UIKit Tags:
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126
Activity
May ’25
The URL authorization read and write obtained by UIDocumentPickerViewController
The URL directory obtained by UIDocumentPickerVieweController can be read and written in the directory after calling startAccessingDecurityScopeResource. However, after restarting the app, if the URL saved in the package is called startAccessingDecurityScopeResource again and returns NO, UIDocumentPickerVieweController must be called again to retrieve the URL, and then startAccessingDecurityScopeResource must be called again before continuing the operation. This is too troublesome. Is there a way to continue reading and writing operations in the URL directory after restarting the app?
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84
Activity
May ’25