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

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iOS 14 UIPickerView Selected View Background Color
I have noticed that in iOS 14 the UIPickerView has by default a light grey background on the selected Row like shown here. https://developer.apple.com/design/human-interface-guidelines/ios/controls/pickers/ I noticed also that pickerView.showsSelectionIndicator is deprecated on iOS 14. Is there a way to change the background color to white and add separators to achieve a pre iOS 14 UIPickerView style? Thank you
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11k
Jun ’25
Issue with multiple touches with "Defer System Gestures" on, with iOS
I'm developing a rhythm game for iOS which has four buttons spanning the width of the screen in portrait. I noticed that my testers were having some missed inputs on the buttons on the left and right due to the fact that iOS, by default, tries to ignore accidental touches on the edges of the screen. So I enabled "Defer System Gestures" on the left and right edges, but then quickly started to notice a new, very specific, issue. Description of the issue If you have finger #1 touching and holding anywhere in the middle of the screen, and finger #2 touches on the far right or left edge of the screen just below the horizontal position of finger #1, those touches are inconsistently not recognized. If finger #1 is not present, this issue does not occur. If finger #2 is above or well below finger #1, this issue also does not occur. A dead zone is created on the right and left edges of the screen just below the horizontal position of the first touch. Here is a rough representative example of where touches #1 and #2 need to be for this issue to manifest, in case the text above is not clear. |				| |				| |				| |				| |	 1		| |			 2| |				| It just so happens that this issue is causing major usability problems with my game, as it results in what the user sees as sporadic and inconsistent response when the game calls for two notes to be played at the same time. Steps to recreate the issue Here are the steps if you want to recreate the problem yourself using the "Create New Gesture" pane in "Assistive Touch" (Note that this problem is not specific to the Settings app, but rather is an issue across the system—however this panel defers system gestures and shows where touches are being read, so it is a great place to demonstrate): (1) Go to Settings > Accessibility > Touch > Assistive Touch > Create New Gesture...; (2) With one finger, touch the middle of the screen and hold it through step 3; (3) With a second finger, tap 4 times along the right (or left) edge of the screen in the following places: (a) well above the vertical position of the first touch, (b) just above the vertical position of the first touch, (c) just below the vertical position of the first touch, and (d) well below the vertical position of the first touch; (4) Notice how, more than half the time, touch (c) does not register. I have found that this problem is more replicatable when the first touch is on the lower half of the screen, but I have been able to replicate it when the finger is higher as well, just not as consistently. Here are the four positions described in the steps above: Position a: both touches register |				| |				| |				| |			 2| |	 1		| |				| |				| Position b: both touches usually register |				| |				| |				| |				| |	 1	 2| |				| |				| Position c: only touch 1 registers |				| |				| |				| |				| |	 1		| |			 2| |				| Position d: both touches register |				| |				| |				| |				| |	 1		| |				| |			 2| Is there anything I can do to resolve this behavior? My app requires gesture deferment to be on for the expected experience by the user, and this bug is causing other issues for my testers that kind of need to be resolved before I can confidently release the game.
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1.3k
Dec ’25
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:
5
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2.7k
Dec ’25
Keyboard Notification UIKit magic.
Dear random Apple UIKit engineer. This is a question for you. Today let's speak about keyboard notifications. In particular, UIResponder.keyboardWillShowNotification and UIResponder.keyboardWillHideNotification. While working with those, I noticed some undocumented behaviour. First, let me give you some context: extension UIViewController { func registerForKeyboardNotifications() { NotificationCenter.default.addObserver(self, selector: #selector(keyboardNotification), name: UIResponder.keyboardWillShowNotification, object: nil) NotificationCenter.default.addObserver(self, selector: #selector(keyboardNotification), name: UIResponder.keyboardWillHideNotification, object: nil) } /// Override this method to handle keyboard notifications. @objc func keyboardNotification(_ notification: Notification) { ... } } Eventually, I found that latter method with 3 dots has an implicit animation inside it's scope. Here is the [proof.](https://medium.com /uptech-team/why-does-uiresponder-keyboard-notification-handler-animate-10cc96bce372) Another thing I noticed, is that this property definition is perfectly valid let curve = UIView.AnimationCurve(rawValue: 7)!. The 7 btw comes from UIResponder.keyboardAnimationCurveUserInfoKey as a default value during my tests. So, the enum with 4 possible values (0...3) can be initialized with a value out of enum's cases range. Also, how can I initialize UIView.AnimationOption from 7? I will pollute my OptionSet which I feed to options parameter on UIView.animate(...) My questions: Why implicit animation is not documented and can I trust it or it's a subject to change. Why UIView.AnimationCurve(rawValue: 7)! does not crash. How can I convert UIResponder.keyboardAnimationCurveUserInfoKey's value into UIView.AnimationOption properly if I don't want to use implicit value. I don't encroach on UIKit secrets. I just need to know how to work with the API. Thank you!
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1.4k
Nov ’25
UITextField with isSecureTextEntry in Catalyst display an empty box
Hi, In a Mac Catalyst app, I need to allow the user insert a passcode using a UITextField. The field is used to insert a one time passcode and I want to keep the content hidden. For this reason I set the isSecureTextEntry property to true. passcodeTextField.isSecureTextEntry = true By doing this, a button to allow the user to pick a password from the keychain is displayed: This option in my case should not appear because the password is a one time password that change every time. For that reason I set the textContentType to oneTimeCode. passcodeTextField.textContentType = .oneTimeCode This actually removes the password button, but introduce something weird. If the user type something and then delete everything, a big empty box appear under the field: I have no idea what this box is and why it appears. Does anyone know why it appears and how I can remove it? Thank you
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881
Apr ’25
UserDefaults.standard was cleared and app UUDI is also changed when I update new version from app store
Facing issue of NSUserDefaults data got cleared on update new version from app store. so all data of user got cleared and user have to login again. I was having app in store with version 1.1.3 and then we have uploaded new version to store with version 1.1.4 but when user download app from store their data was cleared from UserDefaults.so this is big issue in update. need to help. is that apple updated any process on update. Question How Apple change version build in device when we update app from app store. is it uninstall old build and install new build ? Or it is install new version on old version ? Should UserDefaults.standard will delete on update ? Updating Provisioning profile from manual to automatically cause issue on UserDefaults.standard Like UserDefaults got cleared and uuid will change ? Do we have anythings that we can identify specific user as uniq user ? What is better solution to store login data into SQLite store or in UserDefaults as model ? Will appreciate for your help. this is very big issue and login again on update will make app user more effect
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4.0k
May ’25
Using the UIPasteControl
Hello 👋🏽 I am a new iOS developer and I am having a hard time understanding the behavior of the new UIPasteControl to avoid showing the system prompt. Does anyone has any example code I could look at to understand the behavior. Idk how to set the target of the button to the general pasteboard. also I am using objective-c . thanks cristian
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4.1k
Apr ’25
UIDocumentPickerViewController -initForOpeningContentTypes: gives URL to app without permission to read it in Release mode only
I'm using UIDocumentPickerViewController to open a url. Works fine in debug mode but version on the App Store is failing. Code to create the document picker is like: NSArray *theTypes = [UTType typesWithTag:@"docxtensionhere" tagClass:UTTagClassFilenameExtension conformingToType:nil]; UIDocumentPickerViewController *documentPicker = [[UIDocumentPickerViewController alloc]initForOpeningContentTypes:theTypes]; documentPicker.delegate = self;   [self presentViewController:documentPicker animated:YES completion:nil]; So in debug mode this is all gravy. -documentPicker:didPickDocumentsAtURLs: passes back a URL and I can read the file. In release mode I get a URL but my app is denied access to read the file. After inspecting some logging it appears the sandbox is not granting my app permission. error Domain=NSCocoaErrorDomain Code=257 "The file “Filename.fileextensionhere” couldn’t be opened because you don’t have permission to view it." UserInfo={NSFilePath=/private/var/mobile/Library/Mobile Documents/comappleCloudDocs/Filename.fileextensionhere, NSUnderlyingError=0x2834c9da0 {Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"}} -- If I'm doing something wrong with UIDocumentPickerViewController it is a real shame that permission is not being denied in Debug mode, as devs are more likely to catch in prior to release. Anyone know where I'm going wrong and if not have a workaround? Thanks in advance.
9
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2.3k
Sep ’25
Scrolling UICollectionView inside a container view scrolls navigation controller title
I am trying to understand if what I am seeing is expected behavior or not with the following UIKit components. 1.I have a view controller "A" embedded in a navigation controller (part of a multi-step flow). Large titles are active on this navigation controller. In this view controller "A", I have a container view that contains another view controller "B" (I want to reuse the contents of B in other flows) Inside view controller "B" I have a UICollectionView using a diffable data source. When you load view controller "A" it appears to work fine. My collection view loads data, I see a nice list and when I scroll it... ... the expectation is it scrolls inside it's container and has no impact on the parent controller "B" However, the navigation bar and title in "A" reflect the content offset of the collection view. Scroll a couple lines, the large title turns small and centered on top. If I turn off large title, I still see the background color of the navigation bar change as it would if you were scrolling a view directly inside controller "A" without the container view. Am I supposed to be manually capturing the gesture recognizer in B and somehow preventing the gesture to bubble up to A? It seems like strange behavior to have to correct. Any suggestions? Thanks!
Topic: UI Frameworks SubTopic: UIKit Tags:
4
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1.5k
Oct ’25
UIViewRepresentable never dismantled on deletion (MEMORY LEAK)
I have find out that a UIViewRepresentable, even with a simples UIView, seems to never be dismantled when deleted from a ForEach and this can cause serious crashes. In the following example you can observe this behavior by deleting a row from the list. The dismantleUIView function of SomeUIViewRepresentable or the deinit of SomeUIView are never called. Has anyone faced this and found a solution for it? I have also filled a Feedback: FB11979117 class SomeUIView: UIView {     deinit {         print(#function)     } } struct SomeUIViewRepresentable: UIViewRepresentable {     func makeUIView(context: Context) -> SomeUIView {         let uiView = SomeUIView()         uiView.backgroundColor = .systemBlue         return uiView     }     func updateUIView(_ uiView: SomeUIView, context: Context) { }     static func dismantleUIView(_ uiView: SomeUIView, coordinator: Coordinator) {         print(#function)     } } struct Model: Identifiable {     let id = UUID() } struct ContentView: View {     @State var models = [Model(), Model(), Model(), Model(), Model()]     var body: some View {         List {             ForEach(models) { _ in                 SomeUIViewRepresentable()             }             .onDelete {                 models.remove(atOffsets: $0)             }         }     } }
1
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1.5k
May ’25
Occasional Keyboard Cannot Hide in iOS16.5
Help,I have encountered a thorny problem! In systems with iOS 16.5 and above, there is a probability that the keyboard will not disappear after it appears. And once it appears, unless the app is restarted, all places where the keyboard is used cannot be closed. I have tried using the forced shutdown method [UIView endEditing:YES], but it didn't work. When this exception occurs, I notice that there will be two UITextEffectsWindow at the same time. Does anyone know how to solve it?
Topic: UI Frameworks SubTopic: UIKit Tags:
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357
May ’25
Are SVG assets faster than PNG when rendered or not?
I recently was thinking about which is the best format to use for my little icons in the app, and was considering the performance of PNG versus SVG . I know that PNG decoders are hardware accelerated and parallelized, and the rendering is as simple as placing the pixels on the screen. On the other hand, SVG requires computation to determine the placement of pixels based on mathematical equations. Considering this, my current assumption is that PNG is faster to render than SVG. However, if SVG is also hardware-accelerated, it could alter the situation, although this may not be the case.
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2.3k
Oct ’25
New UIButton title left aligned
Hello There, I was trying to do a Button with title left aligned. With the old UIButton, I would have used the title-/contentEdgeInsets to achieve this, but with the new button these values are deprecated and do not work anymore. As far as I understood, with the new button only the spacing between the elements (sub-, title and image) is controllable. I also tried just setting the buttons width to the same width as the label, what would be possible in my case since it should be kind of a "hyperlink-button" which has no background or border. This works so far, but once the user interacts with the button, the title label gets multiline, which is on the one hand not wanted and on the other hand of course does not look left aligned anymore. (Besides the buttons height is fix in my case which leads to clipping of the title) So here again in short: Is there any way to make the title of the new UIButton left aligned inside of the button? Thank you very much in advance.
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1.7k
May ’25
viewIsAppearing not be called in children Controllers below iOS 16?
I see viewIsAppearing is available on iOS 13 and above, but when I use it, found that the function not be called below iOS 16 https://developer.apple.com/documentation/uikit/uiviewcontroller/4195485-viewisappearing environment: Macos 14.4.1, Xcode 15.3 import UIKit class ViewController: UIViewController { override func viewDidLoad() { super.viewDidLoad() let sub = SubViewController() addChild(sub) view.addSubview(sub.view) } @available(iOS 13.0, *) override func viewIsAppearing(_ animated: Bool) { super.viewIsAppearing(animated) print("ViewController viewIsAppearing") } } class SubViewController: UIViewController { @available(iOS 13.0, *) override func viewIsAppearing(_ animated: Bool) { super.viewIsAppearing(animated) print("SubViewController viewIsAppearing") } } In iOS 15 devcice console log: ViewController viewIsAppearing iOS 16, 17: ViewController viewIsAppearing SubViewController viewIsAppearing
Topic: UI Frameworks SubTopic: UIKit Tags:
3
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1k
May ’25
USSD calls with * and # dont work iOS
I have an application that needs to make a USSD call, but on some devices the * and # don't work on the dialer, on others it does. if let phoneNumber = ussdNumberTextfield.text { let encoded = "telprompt:\(phoneNumber)".addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)! if let url = URL(string: encoded) { if application.canOpenURL(url){ DispatchQueue.main.async { self.application.open(url, options: [:]) { success in } } } } }
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1.3k
Jan ’26
iOS app crash with UIKitcore - UIAlertController
I have recently submitted a new app version to the Appstore with Xcode 15.0. Unfortunately, I have started to see the below crash in the Xcode organiser > Crashes section occurring for more number of times. UIKitCore: +[UIAlertController _alertControllerContainedInViewController:] + 160 The exception trace is not leading to main() function but not pointing to any of the code line. I had used UIAlertController in the past versions to show the alerts but there is no code written in the current version code related to UIAlertController. Only from the latest version, this kind of crash started to surface. In the latest release, We have added a third party SDK and while implementing the SDK, we had added the Location and Bluetooth Permissions in Info.plist file. But as we don't want to use/track the Location and Bluetooth details from the app, the SDK team has disabled the Location and Bluetooth settings to not reflect in the tracked data. Is this behaviour creating any conflict with the UIAlertController and logging the crash? Because by default the OS tries to show the alert when the permissions exist in the plist file, but the alert will not come as the service is disabled on the SDK server settings. Is this creating any conflict and logging the crash. Please extend your help.
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885
May ’25
[iOSAppOnMac] ShareKit: Crashes in SHKItemIsPDF() or -[SHKSaveToFilesSharingService saveFileURL:completion:]
I have a custom document-based iOS app that also runs on macOS. After implementing -activityItemsConfiguration to enable sharing from the context menu, I found that the app crashes on macOS when selecting Share… from the context menu and then selecting Save (i.e. Save to Files under iOS). This problem does not occur on iOS, which behaves correctly. - (id<UIActivityItemsConfigurationReading>)activityItemsConfiguration { NSItemProvider * provider = [[NSItemProvider alloc] initWithContentsOfURL:self.document.presentedItemURL]; UIActivityItemsConfiguration * configuration = [UIActivityItemsConfiguration activityItemsConfigurationWithItemProviders:@[ provider ]]; // XXX crashes with com.apple.share.System.SaveToFiles return configuration; } Additionally, I found that to even reach this crash, the workaround implemented in the NSItemProvider (FBxxx) category of the sample project is needed. Without this, the app will crash much earlier, due to SHKItemIsPDF() erroneously invoking -pathExtension on an NSItemProvider. This appears to be a second bug in Apple’s private ShareKit framework. #import <UniformTypeIdentifiers/UniformTypeIdentifiers.h> @implementation NSItemProvider (FBxxx) // XXX SHKItemIsPDF() invokes -pathExtension on an NSItemProvider (when running under macOS, anyway) -> crash - (NSString *)pathExtension { return self.registeredContentTypes.firstObject.preferredFilenameExtension; } @end Again, this all works fine on iOS (17.5) but crashes when the exact same app build is running on macOS (14.5). I believe these bugs are Apple's. Any idea how to avoid the crash? Is there a way to disable the "Save to Files" option in the sharing popup? I filed FB13819800 with a sample project that demonstrates the crash on macOS. I was going to file a TSI to get this resolved, but I see that DTS is not responding to tech support incidents until after WWDC.
Topic: UI Frameworks SubTopic: UIKit
8
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693
Jul ’25
Regression in UITabBarController on Catalyst when building under Xcode 16
I am running into an issue with UITabBarController in a Catalyst app when building under Xcode 16 and running on macOS 15. If a UITabBarController is used, the tabs are presented in an unwanted title/toolbar at the top of the window. If you have an app where your views run to the top of the window, this can obscure the content and controls that are near the top. I created a sample application that is attached to the Feedback record (FB14293963). When building under Xcode 15, this is what the app looks like: Under Xcode 16, it looks like this: Beyond this simple example, using UITabBarController in a presented view controller can result in the tabs not showing at all. Also, If you switch the view in the main window to something that isn't a UITabBarController, the tabs still remain at the top. This seems to stem from the tab bar/sidebar changes for iPadOS 18. While this approach can work for simpler apps, it may not work well at all for more complex apps and there really needs to be a way to opt out of this behavior so apps where it is not suited for can still take advantage of features in iPadOS/Catalyst 18. Has anyone discovered a workaround or way to disable the new tab bar behavior with having to write their own version of UITabBarController?
2
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1.4k
Jul ’25
UITextView's pressesBegan isn't triggered by the software keyboard
I'm building a SwiftUI app with a UITextView subclass, and it seems that the software keyboard doesn't trigger the pressesBegan or pressesEnded functions of UITextView. With a hardware keyboard, pressesBegan works as expected, allowing us to intercept key presses in our subclass. I can't find any documentation about this, or any other forum posts (here or on Stack Overflow) that talk about a discrepancy between software and hardware keyboard behaviors, and I can't believe this is an intended behavior. Our app is a SwiftUI app, in case that's relevant. Does anyone have any guidance? Is this a bug or am I not understanding this API? Any information or work arounds would be greatly appreciated. I've made a sample project that demonstrates this issue, which you can grab from GitHub at https://github.com/nyousefi/KeyPressSample. To see this in action, run the sample project and start pressing keys. The hardware keyboard will print the key press at the top of the screen (above the text view), while the software keyboard won't.
3
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741
May ’25
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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1.1k
Sep ’25
iOS 14 UIPickerView Selected View Background Color
I have noticed that in iOS 14 the UIPickerView has by default a light grey background on the selected Row like shown here. https://developer.apple.com/design/human-interface-guidelines/ios/controls/pickers/ I noticed also that pickerView.showsSelectionIndicator is deprecated on iOS 14. Is there a way to change the background color to white and add separators to achieve a pre iOS 14 UIPickerView style? Thank you
Replies
9
Boosts
0
Views
11k
Activity
Jun ’25
Issue with multiple touches with "Defer System Gestures" on, with iOS
I'm developing a rhythm game for iOS which has four buttons spanning the width of the screen in portrait. I noticed that my testers were having some missed inputs on the buttons on the left and right due to the fact that iOS, by default, tries to ignore accidental touches on the edges of the screen. So I enabled "Defer System Gestures" on the left and right edges, but then quickly started to notice a new, very specific, issue. Description of the issue If you have finger #1 touching and holding anywhere in the middle of the screen, and finger #2 touches on the far right or left edge of the screen just below the horizontal position of finger #1, those touches are inconsistently not recognized. If finger #1 is not present, this issue does not occur. If finger #2 is above or well below finger #1, this issue also does not occur. A dead zone is created on the right and left edges of the screen just below the horizontal position of the first touch. Here is a rough representative example of where touches #1 and #2 need to be for this issue to manifest, in case the text above is not clear. |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9; 1&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9; 2| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| It just so happens that this issue is causing major usability problems with my game, as it results in what the user sees as sporadic and inconsistent response when the game calls for two notes to be played at the same time. Steps to recreate the issue Here are the steps if you want to recreate the problem yourself using the "Create New Gesture" pane in "Assistive Touch" (Note that this problem is not specific to the Settings app, but rather is an issue across the system—however this panel defers system gestures and shows where touches are being read, so it is a great place to demonstrate): (1) Go to Settings &gt; Accessibility &gt; Touch &gt; Assistive Touch &gt; Create New Gesture...; (2) With one finger, touch the middle of the screen and hold it through step 3; (3) With a second finger, tap 4 times along the right (or left) edge of the screen in the following places: (a) well above the vertical position of the first touch, (b) just above the vertical position of the first touch, (c) just below the vertical position of the first touch, and (d) well below the vertical position of the first touch; (4) Notice how, more than half the time, touch (c) does not register. I have found that this problem is more replicatable when the first touch is on the lower half of the screen, but I have been able to replicate it when the finger is higher as well, just not as consistently. Here are the four positions described in the steps above: Position a: both touches register |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9; 2| |&amp;#9; 1&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| Position b: both touches usually register |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9; 1&amp;#9; 2| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| Position c: only touch 1 registers |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9; 1&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9; 2| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| Position d: both touches register |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9; 1&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9;&amp;#9;| |&amp;#9;&amp;#9;&amp;#9; 2| Is there anything I can do to resolve this behavior? My app requires gesture deferment to be on for the expected experience by the user, and this bug is causing other issues for my testers that kind of need to be resolved before I can confidently release the game.
Replies
2
Boosts
2
Views
1.3k
Activity
Dec ’25
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:
Replies
5
Boosts
3
Views
2.7k
Activity
Dec ’25
Keyboard Notification UIKit magic.
Dear random Apple UIKit engineer. This is a question for you. Today let's speak about keyboard notifications. In particular, UIResponder.keyboardWillShowNotification and UIResponder.keyboardWillHideNotification. While working with those, I noticed some undocumented behaviour. First, let me give you some context: extension UIViewController { func registerForKeyboardNotifications() { NotificationCenter.default.addObserver(self, selector: #selector(keyboardNotification), name: UIResponder.keyboardWillShowNotification, object: nil) NotificationCenter.default.addObserver(self, selector: #selector(keyboardNotification), name: UIResponder.keyboardWillHideNotification, object: nil) } /// Override this method to handle keyboard notifications. @objc func keyboardNotification(_ notification: Notification) { ... } } Eventually, I found that latter method with 3 dots has an implicit animation inside it's scope. Here is the [proof.](https://medium.com /uptech-team/why-does-uiresponder-keyboard-notification-handler-animate-10cc96bce372) Another thing I noticed, is that this property definition is perfectly valid let curve = UIView.AnimationCurve(rawValue: 7)!. The 7 btw comes from UIResponder.keyboardAnimationCurveUserInfoKey as a default value during my tests. So, the enum with 4 possible values (0...3) can be initialized with a value out of enum's cases range. Also, how can I initialize UIView.AnimationOption from 7? I will pollute my OptionSet which I feed to options parameter on UIView.animate(...) My questions: Why implicit animation is not documented and can I trust it or it's a subject to change. Why UIView.AnimationCurve(rawValue: 7)! does not crash. How can I convert UIResponder.keyboardAnimationCurveUserInfoKey's value into UIView.AnimationOption properly if I don't want to use implicit value. I don't encroach on UIKit secrets. I just need to know how to work with the API. Thank you!
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3
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1.4k
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Nov ’25
UITextField with isSecureTextEntry in Catalyst display an empty box
Hi, In a Mac Catalyst app, I need to allow the user insert a passcode using a UITextField. The field is used to insert a one time passcode and I want to keep the content hidden. For this reason I set the isSecureTextEntry property to true. passcodeTextField.isSecureTextEntry = true By doing this, a button to allow the user to pick a password from the keychain is displayed: This option in my case should not appear because the password is a one time password that change every time. For that reason I set the textContentType to oneTimeCode. passcodeTextField.textContentType = .oneTimeCode This actually removes the password button, but introduce something weird. If the user type something and then delete everything, a big empty box appear under the field: I have no idea what this box is and why it appears. Does anyone know why it appears and how I can remove it? Thank you
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1
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1
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881
Activity
Apr ’25
UserDefaults.standard was cleared and app UUDI is also changed when I update new version from app store
Facing issue of NSUserDefaults data got cleared on update new version from app store. so all data of user got cleared and user have to login again. I was having app in store with version 1.1.3 and then we have uploaded new version to store with version 1.1.4 but when user download app from store their data was cleared from UserDefaults.so this is big issue in update. need to help. is that apple updated any process on update. Question How Apple change version build in device when we update app from app store. is it uninstall old build and install new build ? Or it is install new version on old version ? Should UserDefaults.standard will delete on update ? Updating Provisioning profile from manual to automatically cause issue on UserDefaults.standard Like UserDefaults got cleared and uuid will change ? Do we have anythings that we can identify specific user as uniq user ? What is better solution to store login data into SQLite store or in UserDefaults as model ? Will appreciate for your help. this is very big issue and login again on update will make app user more effect
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4
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1
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4.0k
Activity
May ’25
Using the UIPasteControl
Hello 👋🏽 I am a new iOS developer and I am having a hard time understanding the behavior of the new UIPasteControl to avoid showing the system prompt. Does anyone has any example code I could look at to understand the behavior. Idk how to set the target of the button to the general pasteboard. also I am using objective-c . thanks cristian
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5
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4.1k
Activity
Apr ’25
UIDocumentPickerViewController -initForOpeningContentTypes: gives URL to app without permission to read it in Release mode only
I'm using UIDocumentPickerViewController to open a url. Works fine in debug mode but version on the App Store is failing. Code to create the document picker is like: NSArray *theTypes = [UTType typesWithTag:@"docxtensionhere" tagClass:UTTagClassFilenameExtension conformingToType:nil]; UIDocumentPickerViewController *documentPicker = [[UIDocumentPickerViewController alloc]initForOpeningContentTypes:theTypes]; documentPicker.delegate = self;   [self presentViewController:documentPicker animated:YES completion:nil]; So in debug mode this is all gravy. -documentPicker:didPickDocumentsAtURLs: passes back a URL and I can read the file. In release mode I get a URL but my app is denied access to read the file. After inspecting some logging it appears the sandbox is not granting my app permission. error Domain=NSCocoaErrorDomain Code=257 "The file “Filename.fileextensionhere” couldn’t be opened because you don’t have permission to view it." UserInfo={NSFilePath=/private/var/mobile/Library/Mobile Documents/comappleCloudDocs/Filename.fileextensionhere, NSUnderlyingError=0x2834c9da0 {Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"}} -- If I'm doing something wrong with UIDocumentPickerViewController it is a real shame that permission is not being denied in Debug mode, as devs are more likely to catch in prior to release. Anyone know where I'm going wrong and if not have a workaround? Thanks in advance.
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9
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2.3k
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Sep ’25
Scrolling UICollectionView inside a container view scrolls navigation controller title
I am trying to understand if what I am seeing is expected behavior or not with the following UIKit components. 1.I have a view controller "A" embedded in a navigation controller (part of a multi-step flow). Large titles are active on this navigation controller. In this view controller "A", I have a container view that contains another view controller "B" (I want to reuse the contents of B in other flows) Inside view controller "B" I have a UICollectionView using a diffable data source. When you load view controller "A" it appears to work fine. My collection view loads data, I see a nice list and when I scroll it... ... the expectation is it scrolls inside it's container and has no impact on the parent controller "B" However, the navigation bar and title in "A" reflect the content offset of the collection view. Scroll a couple lines, the large title turns small and centered on top. If I turn off large title, I still see the background color of the navigation bar change as it would if you were scrolling a view directly inside controller "A" without the container view. Am I supposed to be manually capturing the gesture recognizer in B and somehow preventing the gesture to bubble up to A? It seems like strange behavior to have to correct. Any suggestions? Thanks!
Topic: UI Frameworks SubTopic: UIKit Tags:
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4
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1.5k
Activity
Oct ’25
UIViewRepresentable never dismantled on deletion (MEMORY LEAK)
I have find out that a UIViewRepresentable, even with a simples UIView, seems to never be dismantled when deleted from a ForEach and this can cause serious crashes. In the following example you can observe this behavior by deleting a row from the list. The dismantleUIView function of SomeUIViewRepresentable or the deinit of SomeUIView are never called. Has anyone faced this and found a solution for it? I have also filled a Feedback: FB11979117 class SomeUIView: UIView {     deinit {         print(#function)     } } struct SomeUIViewRepresentable: UIViewRepresentable {     func makeUIView(context: Context) -> SomeUIView {         let uiView = SomeUIView()         uiView.backgroundColor = .systemBlue         return uiView     }     func updateUIView(_ uiView: SomeUIView, context: Context) { }     static func dismantleUIView(_ uiView: SomeUIView, coordinator: Coordinator) {         print(#function)     } } struct Model: Identifiable {     let id = UUID() } struct ContentView: View {     @State var models = [Model(), Model(), Model(), Model(), Model()]     var body: some View {         List {             ForEach(models) { _ in                 SomeUIViewRepresentable()             }             .onDelete {                 models.remove(atOffsets: $0)             }         }     } }
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1.5k
Activity
May ’25
Occasional Keyboard Cannot Hide in iOS16.5
Help,I have encountered a thorny problem! In systems with iOS 16.5 and above, there is a probability that the keyboard will not disappear after it appears. And once it appears, unless the app is restarted, all places where the keyboard is used cannot be closed. I have tried using the forced shutdown method [UIView endEditing:YES], but it didn't work. When this exception occurs, I notice that there will be two UITextEffectsWindow at the same time. Does anyone know how to solve it?
Topic: UI Frameworks SubTopic: UIKit Tags:
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1
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2
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357
Activity
May ’25
Are SVG assets faster than PNG when rendered or not?
I recently was thinking about which is the best format to use for my little icons in the app, and was considering the performance of PNG versus SVG . I know that PNG decoders are hardware accelerated and parallelized, and the rendering is as simple as placing the pixels on the screen. On the other hand, SVG requires computation to determine the placement of pixels based on mathematical equations. Considering this, my current assumption is that PNG is faster to render than SVG. However, if SVG is also hardware-accelerated, it could alter the situation, although this may not be the case.
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3
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0
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2.3k
Activity
Oct ’25
New UIButton title left aligned
Hello There, I was trying to do a Button with title left aligned. With the old UIButton, I would have used the title-/contentEdgeInsets to achieve this, but with the new button these values are deprecated and do not work anymore. As far as I understood, with the new button only the spacing between the elements (sub-, title and image) is controllable. I also tried just setting the buttons width to the same width as the label, what would be possible in my case since it should be kind of a "hyperlink-button" which has no background or border. This works so far, but once the user interacts with the button, the title label gets multiline, which is on the one hand not wanted and on the other hand of course does not look left aligned anymore. (Besides the buttons height is fix in my case which leads to clipping of the title) So here again in short: Is there any way to make the title of the new UIButton left aligned inside of the button? Thank you very much in advance.
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2
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1.7k
Activity
May ’25
viewIsAppearing not be called in children Controllers below iOS 16?
I see viewIsAppearing is available on iOS 13 and above, but when I use it, found that the function not be called below iOS 16 https://developer.apple.com/documentation/uikit/uiviewcontroller/4195485-viewisappearing environment: Macos 14.4.1, Xcode 15.3 import UIKit class ViewController: UIViewController { override func viewDidLoad() { super.viewDidLoad() let sub = SubViewController() addChild(sub) view.addSubview(sub.view) } @available(iOS 13.0, *) override func viewIsAppearing(_ animated: Bool) { super.viewIsAppearing(animated) print("ViewController viewIsAppearing") } } class SubViewController: UIViewController { @available(iOS 13.0, *) override func viewIsAppearing(_ animated: Bool) { super.viewIsAppearing(animated) print("SubViewController viewIsAppearing") } } In iOS 15 devcice console log: ViewController viewIsAppearing iOS 16, 17: ViewController viewIsAppearing SubViewController viewIsAppearing
Topic: UI Frameworks SubTopic: UIKit Tags:
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3
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1k
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May ’25
USSD calls with * and # dont work iOS
I have an application that needs to make a USSD call, but on some devices the * and # don't work on the dialer, on others it does. if let phoneNumber = ussdNumberTextfield.text { let encoded = "telprompt:\(phoneNumber)".addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)! if let url = URL(string: encoded) { if application.canOpenURL(url){ DispatchQueue.main.async { self.application.open(url, options: [:]) { success in } } } } }
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5
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1.3k
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Jan ’26
iOS app crash with UIKitcore - UIAlertController
I have recently submitted a new app version to the Appstore with Xcode 15.0. Unfortunately, I have started to see the below crash in the Xcode organiser &gt; Crashes section occurring for more number of times. UIKitCore: +[UIAlertController _alertControllerContainedInViewController:] + 160 The exception trace is not leading to main() function but not pointing to any of the code line. I had used UIAlertController in the past versions to show the alerts but there is no code written in the current version code related to UIAlertController. Only from the latest version, this kind of crash started to surface. In the latest release, We have added a third party SDK and while implementing the SDK, we had added the Location and Bluetooth Permissions in Info.plist file. But as we don't want to use/track the Location and Bluetooth details from the app, the SDK team has disabled the Location and Bluetooth settings to not reflect in the tracked data. Is this behaviour creating any conflict with the UIAlertController and logging the crash? Because by default the OS tries to show the alert when the permissions exist in the plist file, but the alert will not come as the service is disabled on the SDK server settings. Is this creating any conflict and logging the crash. Please extend your help.
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3
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885
Activity
May ’25
[iOSAppOnMac] ShareKit: Crashes in SHKItemIsPDF() or -[SHKSaveToFilesSharingService saveFileURL:completion:]
I have a custom document-based iOS app that also runs on macOS. After implementing -activityItemsConfiguration to enable sharing from the context menu, I found that the app crashes on macOS when selecting Share… from the context menu and then selecting Save (i.e. Save to Files under iOS). This problem does not occur on iOS, which behaves correctly. - (id<UIActivityItemsConfigurationReading>)activityItemsConfiguration { NSItemProvider * provider = [[NSItemProvider alloc] initWithContentsOfURL:self.document.presentedItemURL]; UIActivityItemsConfiguration * configuration = [UIActivityItemsConfiguration activityItemsConfigurationWithItemProviders:@[ provider ]]; // XXX crashes with com.apple.share.System.SaveToFiles return configuration; } Additionally, I found that to even reach this crash, the workaround implemented in the NSItemProvider (FBxxx) category of the sample project is needed. Without this, the app will crash much earlier, due to SHKItemIsPDF() erroneously invoking -pathExtension on an NSItemProvider. This appears to be a second bug in Apple’s private ShareKit framework. #import <UniformTypeIdentifiers/UniformTypeIdentifiers.h> @implementation NSItemProvider (FBxxx) // XXX SHKItemIsPDF() invokes -pathExtension on an NSItemProvider (when running under macOS, anyway) -> crash - (NSString *)pathExtension { return self.registeredContentTypes.firstObject.preferredFilenameExtension; } @end Again, this all works fine on iOS (17.5) but crashes when the exact same app build is running on macOS (14.5). I believe these bugs are Apple's. Any idea how to avoid the crash? Is there a way to disable the "Save to Files" option in the sharing popup? I filed FB13819800 with a sample project that demonstrates the crash on macOS. I was going to file a TSI to get this resolved, but I see that DTS is not responding to tech support incidents until after WWDC.
Topic: UI Frameworks SubTopic: UIKit
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8
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3
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693
Activity
Jul ’25
Regression in UITabBarController on Catalyst when building under Xcode 16
I am running into an issue with UITabBarController in a Catalyst app when building under Xcode 16 and running on macOS 15. If a UITabBarController is used, the tabs are presented in an unwanted title/toolbar at the top of the window. If you have an app where your views run to the top of the window, this can obscure the content and controls that are near the top. I created a sample application that is attached to the Feedback record (FB14293963). When building under Xcode 15, this is what the app looks like: Under Xcode 16, it looks like this: Beyond this simple example, using UITabBarController in a presented view controller can result in the tabs not showing at all. Also, If you switch the view in the main window to something that isn't a UITabBarController, the tabs still remain at the top. This seems to stem from the tab bar/sidebar changes for iPadOS 18. While this approach can work for simpler apps, it may not work well at all for more complex apps and there really needs to be a way to opt out of this behavior so apps where it is not suited for can still take advantage of features in iPadOS/Catalyst 18. Has anyone discovered a workaround or way to disable the new tab bar behavior with having to write their own version of UITabBarController?
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2
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1.4k
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Jul ’25
UITextView's pressesBegan isn't triggered by the software keyboard
I'm building a SwiftUI app with a UITextView subclass, and it seems that the software keyboard doesn't trigger the pressesBegan or pressesEnded functions of UITextView. With a hardware keyboard, pressesBegan works as expected, allowing us to intercept key presses in our subclass. I can't find any documentation about this, or any other forum posts (here or on Stack Overflow) that talk about a discrepancy between software and hardware keyboard behaviors, and I can't believe this is an intended behavior. Our app is a SwiftUI app, in case that's relevant. Does anyone have any guidance? Is this a bug or am I not understanding this API? Any information or work arounds would be greatly appreciated. I've made a sample project that demonstrates this issue, which you can grab from GitHub at https://github.com/nyousefi/KeyPressSample. To see this in action, run the sample project and start pressing keys. The hardware keyboard will print the key press at the top of the screen (above the text view), while the software keyboard won't.
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3
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741
Activity
May ’25
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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9
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1.1k
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Sep ’25