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

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Mac Catalyst: Presenting view controller <UIAlertController:> from detached view controller <MyViewController:> is not supported, and may result in incorrect safe area insets and a corrupt root presentation on Sonoma
Okay so I'm getting this log every time I present a UIAlertController: Mac Catalyst: Presenting view controller <UIAlertController: 0x10f027000> from detached view controller <MyViewController: 0x10d104080> is not supported, and may result in incorrect safe area insets and a corrupt root presentation. Make sure <MyViewController: 0x10d104080> is in the view controller hierarchy before presenting from it. Will become a hard exception in a future release. A few points: MyViewController is not detached and the presentation shows just fine. I specifically check for this before presenting the alert controller like so: BOOL okayToPresentError = (self.isViewLoaded && self.view.window != nil); if (okayToPresentError) { [self presentErrorInAlertController:error]; } else { //Wait until view did appear. self.errorToPresentInViewDidAppear = error; } It spews out every time an error is fed back to my app and I present the alert controller (I can turn off the network connection and I show an alert controller with a "retry" button in it which will loop the error back so I can replay the error alert presentation over and over again) . Every time the alert controller is presented, I get this spewing in the console. Please don't start throwing hard exceptions because the check is faulty.
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1.9k
Oct ’23
Cannot determine shown/hidden status of a v3 Audio Unit on macOS
I have some visualisation-heavy AUv3's, and the goal is not to perform graphics-intensive tasks if the plugin window is not opened inside the host app (such as Logic Pro). On iOS, this is easily accomplished by the viewWillAppear, etc overrides. But on macOS, it seems these overrides are not called every time the user opens / closes the plugin windows in the host application. I did try some alternate methods, like trying to traverse the view / controller hierarchy, or make use of the window property, to no avail. What substitute mechanism could I use to determine visibility status of an AUv3 on macOS? Thanks in advance, Zoltan
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1.5k
Oct ’23
iOS 17 - New status bar default style doesn't work if the status bar was previously hidden
Hi, I adopted in my app the new default style for the status bar where it switches between light and dark themes depending on the color of the content beneath. It works great until I hide the status bar and show it again. From that point onwards, the status bar will be stuck on the dark or light theme, depending on the app's theme. This happens as well if the status bar is initially hidden on startup. In that case, the default behavior never works. I filed an issue (FB13222217), and as of now I didn't find a workaround except never hiding the status bar on my app. I attached a super minimalist example project there, just a scroll view with black and white views and nothing more. This happens on SwiftUI and UIKit as well. I hope the issue can be addressed and will appreciate if anyone has a workaround for this to let me know. Thanks!
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3.8k
Oct ’23
Navigation bar not shown in Supplementary view of a UISplitView in macOS Sonoma
I've run into a problem that has been giving me fits for a while and have yet to be able to find a solution. We have a Catalyst app that uses a three-pane UISplitView. The middle and third panes show the navigation bar of the UINavigationController hosted in each pane. However, when building under Xcode 15, the navigation bar is not shown in the middle pane when running under macOS 14. It is shown, as expected, when the app is run under prior versions of macOS. It also appears as it should under macOS 14 if the app is built with Xcode 14. If you push another view controller onto the navigation controller's stack with the animate flag set to true, the navigation bar will appear. When you go back to the root controller, the navigation bar is present as it should be. However, if you push the controller with the animate flag set to false, the navigation bar does not appear. I've been able to reproduce this in an isolated test app with just the relevant components. The first screenshot at the end is from a test app that illustrates the problem. The second screenshot shows what it should look like (and does look like under macOS 13). It should be noted that UINavigationBar.appearance().preferredBehavioralStyle = .pad is set. If any Apple folk would kindly like to look into this, I created a feedback for it: FB13260893. The feedback entry has a sample app, screenshots, and even a screen recording demonstrating the problem. Has anyone else run into this or does anyone have any suggestions for a fix/workaround? Thanks, Kevin
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979
Oct ’23
UIAlertController no longer appears as a popover in macOS Sonoma
Prior to macOS 14, a Catalyst app could present a UIAlertController as a popover, just as you can on the iPad. While this still works on the iPad, the presentation on macOS now uses the same style as the iPhone. The UIAlertController's popoverPresentationController property is always nil, no matter how it is configured. Doe anyone know of a way to restore the prior behavior under Sonoma?
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1.2k
Oct ’23
UIPrintInteractionController.shared on Mac OS Sonoma running iPad App
After updating to Mac OS Sonoma, we have encountered compatibility issues with our iPad-designed application, specifically with the AirPrint functionality, when it is run on MacOS. The AirPrint feature stopped working properly through UIPrintInteractionController.shared. We have noticed that when we compile the application using Catalyst, the AirPrint functionality is restored and works as expected. However, this solution is not viable for us due to the restrictions associated with the frameworks we are utilizing. We are seeking alternative solutions, and any help or guidance would be highly appreciated to resolve this issue and ensure a seamless and uninterrupted user experience in our application. STEPS TO REPRODUCE Create an app for ipad with just a button and this code var str = "TEST" let printInfo = UIPrintInfo(dictionary:nil) printInfo.outputType = .general printInfo.jobName = "Report" printInfo.orientation = .portrait let printController = UIPrintInteractionController.shared printController.printInfo = printInfo printController.showsNumberOfCopies = false printController.showsPageRange = false printController.showsNumberOfCopies = false let formatter = UIMarkupTextPrintFormatter(markupText: str) formatter.contentInsets = UIEdgeInsets(top: 72, left: 72, bottom: 72, right: 72) printController.printFormatter = formatter printController.present(animated: true, completionHandler: nil) 2.Run it on a MacOS with Sonoma, there is no error on console or anything but it don't work. -If you run it with Catalyst it just works when adding the Printing permission of App Sandbox in Signing & Capabilities.
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2.8k
Oct ’23
Cannot reorder rows in UITableView under Mac Catalyst
It appears that we are not able to reorder rows in our tables when running our iOS/iPadOS app under Mac Catalyst. It appears that all the delegate methods are returning true indicating the row can be moved and edited. The reordering handles appear in editing move and the row can be moved around (also using drag and drop) but the user interface is not indicating that the row can be dropped to be reordered. It's as if the proposed destination path is being rejected. I tried setting up that delegate method (thinking that maybe the default for that is messed up on Mac Catalyst) but it had no effect. Every table in our system performs this way. Here is a link to an example video that shows the table view not working: https://onsongapp.s3.amazonaws.com/Reordering%20Example.mp4 Please advise if there is something else that needs to be implemented or changed for Mac Catalyst to properly handle table cell reordering.
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869
Nov ’23
Share submenu in Mac Catalyst and UICommandTagShare
With Mac Catalyst, in Big Sur and Monterey, you could use UICommandTagShare as the property list for a UICommand in combination with activityItemsConfiguration and itemProvidersForActivityItemsConfiguration to allow a "Share" submenu to appear in a menu in your app (for instance, under the File menu like many other apps). Starting in Ventura, this submenu no longer appears with that same code, and instead the UICommandTagShare command in the menu now just displays "Share" with no submenu, which triggers a UIActivityViewController to appear in the main window. Is there any way to still allow a Share submenu to work in Ventura and beyond with Mac Catalyst? Thanks so much for any help!
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Dec ’23
Changing presentation style crashes app
Hello! I've been digging into this for a little bit now, and am hitting something of a wall. Our app is crashing occasionally, and googling the crash yields literally 0 results. Tl;dr: Something related to adaptivePresentationStyle(for:traitCollection:) is resulting in our app crashing. Context In our app, we have a custom UIPresentationController that we use to present a small sheet of content overlaying other app content - similar to a UISheetPresentationController with a medium-ish size. So we have a custom UIViewController to present, and it conforms to the UIAdaptivePresentationControllerDelegate protocol. We also have custom present and dismiss animators. The crash However, we seem to be running into a really odd crash. I've attached a crash report as well, but here's what one sees in xcode on reproducing the crash: The _computeToEndFrameForCurrentTransition block is nil inside the _transitionViewForCurrentTransition block, value of outerStrongSelf currently : <XxxYyyyyyZzz.PopupPresentationController: 0x12d017a40>. This most likely indicates that an adaptation is happening after a transtion cleared out _computeToEndFrameForCurrentTransition. Captured debug information outside block: presentationController : <XxxYyyyyyZzz.PopupPresentationController: 0x12d017a40> presentedViewController : <XxxYyyyyyZzz.SomeViewController: 0x12d03a690> presentingViewController : <UINavigationController: 0x12a817400> 2023-09-25_08-02-33.6523_-0500-7d355cd4a86427213389765ef070a777c4b4aaa3.crash Whenever we present one of these view controllers, things work just fine. When we try to present another one though, if someone is aggressively changing the phone orientation, the app crashes. This crash occurs somewhere in between dismissing the old VC and presenting the new one. It occurs before I ever hit any breakpoints in the "present" animator for the second view controller. I've narrowed things down a bit, and by commenting out our implementation of adaptivePresentationStyle(for:traitCollection:), the crash can't be reproduced anymore. The downside there being that the app no longer functions how we want it to. Our definition of that function (which causes crashes) looks like this: public func adaptivePresentationStyle(for controller: UIPresentationController, traitCollection: UITraitCollection) -> UIModalPresentationStyle { guard forceUsingFullScreenIfCompact else { return .none } return traitCollection.verticalSizeClass == .compact ? .overFullScreen : .none } A bit more testing, and it seems like if that function returns the same thing consistently, nothing crashes. Are we not allowed to put conditional logic in this function? In the crash, we can see that it occurs due to a failing assertion internal to UIPresentationController: Last Exception Backtrace: 0 CoreFoundation 0x1afa28cb4 __exceptionPreprocess + 164 (NSException.m:202) 1 libobjc.A.dylib 0x1a8abc3d0 objc_exception_throw + 60 (objc-exception.mm:356) 2 Foundation 0x1aa1b2688 -[NSAssertionHandler handleFailureInFunction:file:lineNumber:description:] + 172 (NSException.m:251) 3 UIKitCore 0x1b1d05610 __80-[UIPresentationController _initViewHierarchyForPresentationSuperview:inWindow:]_block_invoke + 2588 (UIPresentationController.m:1594) 4 UIKitCore 0x1b21f1ff4 __56-[UIPresentationController runTransitionForCurrentState]_block_invoke_3 + 300 (UIPresentationController.m:1228) The question This all leads us to wonder if we're doing something wrong, or if there could be a bug in one of the iOS APIs that we're consuming. Thus, posting here. Does anyone have any insight into how this could be occurring, or has seen this before and has ideas? Thanks! Miscellaneous info We target iOS 14+ We've seen this issue in debug and release builds from Xcode 14 and 15 We see the issue on users with iOS 15+, though it could be occurring on 14 in just incredibly low numbers This is a re-post of https://developer.apple.com/forums/thread/738257, because I accidentally closed that out as resolved
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1k
Dec ’23
View appears transparent over tableView, whatever alpha channel
I have a view in storyboard, with a tableView and a coloured UIView. The UIView is declared after tableView, so it appears on top of tableView. However, it appears semi transparent over the tableView. In addition, I cannot set its alpha channel to values other than 1 or 0 (e.g., 0.9) But if I create the view programmatically, the view if fully opaque as expected. What am I missing ?
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966
Dec ’23
Detect foreground/background change
In ios17 and above, I can detect when swiftUI app goes into and out of background using: @Environment(\.scenePhase) private var phase ... .onChange(of: phase) { switch phase { case .background: print("entering background...") case .active: print("entering foreground...") default: break } } Is there a straightforward way to do this in SwiftUI for ios 16? I've found some examples using UIKit, but I am not that swift (sorry, couldn't resist) with that framework.
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2.4k
Jan ’24
Full keyboard access UI elements
Hello, Since the full keyboard access Help menu is a little vague on the nuances between Tab, arrow keys, and Ctrl+tab in terms of navigation, could you point me to where I can find the intended mapping of FKA keys to UI elements? For example, I have been in several Apple iOS apps where the UITabBar at the bottom is navigable with any of the three options mentioned above. In other contexts, the tab key only moves the user to the tab bar section, then the icons are focusable with arrow or Ctrl + tab. When a modal pops up stating I will be leaving an app, should the choices be navigable with Tab? Ctrl+tab? or arrows too? In other places, like news articles in Apple News, it seems that I cannot scroll with the arrow keys to read the various paragraphs, nor interact with links at all that are in the article. If there is a separate keyboard shortcut for links or scrollbar, please update the Help menu. It seems pretty straightforward that arrow keys navigate between HStacks and VStacks. Is that an accurate guess of arrow key behavior? I feel like I'm guessing in several places within the content groups.
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1.9k
Feb ’24
Disable AutoFill option in UITextField or have control over the text which is being pasted using that option.
I have form fields in an app, I have some validations to perform like phone number should only have digits and not alphabets, however when user uses AutoFill option doing long press on textfield they have option to choose Contacts and they can tap on name and it will paste alphabets in my Phone number field, that behavior I don't want as my validations will not be fulfilled. There are no callbacks to detect and prevent that text from being pasted. In shouldChangeCharactersIn delegate method even if I return false for that paste event it ignores that and forcefully it gets pasted. Please help how to tackle such scenarios to perform above mentioned validations. Thanks
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1.9k
Mar ’24
How do I inject reference types in a table view cell and reload the row of the said cell without causing a memory leak?
For instance, executing the following code, in which a stepper is injected in a table view cell and the cell is reloaded when the user changes the stepper's value, causes the memory usage to grow pretty quickly (I stopped the simulation at 1GB) when you tap on the stepper. Also the CPU usage jumps straight at 99%, and the UI freezes. Note: I'd like to know exactly what I asked, not how to make a table view cell with a stepper in general. I know that calling reloadData() or reconfigureRows(at:) doesn't cause any of the mentioned issues. Also please don't reply with questions like "Have you tried to use weak references?". The code is short: please reply with a working solution if you can. class ViewController: UIViewController { let tableView = UITableView() let stepper = UIStepper() override func viewDidLoad() { super.viewDidLoad() view.addSubview(tableView) tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell") tableView.dataSource = self stepper.addTarget(self, action: #selector(stepperValueChanged), for: .valueChanged) } override func viewDidLayoutSubviews() { super.viewDidLayoutSubviews() tableView.frame = view.bounds } @objc private func stepperValueChanged() { tableView.reloadRows(at: [IndexPath(row: 0, section: 0)], with: .automatic) } } extension ViewController: UITableViewDataSource { func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int { 1 } func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell { let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) cell.accessoryView = stepper var configuration = cell.defaultContentConfiguration() configuration.text = "\(stepper.value)" cell.contentConfiguration = configuration return cell } }
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498
Mar ’24