I'm currently developing a custom keyboard which bundled with main app. The keyboard would randomly crash when switch between apps with opened custom keyboard on physical device. I've read posts around but seems not what I've encountered. Bundle ID of main app: com.company.appName Bundle ID of keyboard extension: com.company.appName.Keyboard When custom keyboard is opened second time on other app, a sole personality warning would show up, but this won't lead to crash. WARNING! Sole personality is ambiguous; this may lead to erratic behavior [lifecycle] [u 9A2D7B1D-20AF-4E2A-A72F-C37C8D4FDEEA] [com.company.appName.Keyboard(1.0.0)] WARNING! Sole personality is ambiguous; this may lead to erratic behavior; personalities: { "com.companyName.appName.keyboard" = { 19209 = "<PKServicePersonality: 0x28299da00; core = <[u 9A2D7B1D-20AF-4E2A-A72F-C37C8D4FDEEA] [com.company.appName.Keyboard(1.0.0)],[d (null)] [/private/var/containers/Bundle/Application/67892ACC-5BDA-4205-828D-4D94D6E87ABD/AppName.app/PlugIns/Keyboard.appex]>, host pid = 19209>"; 19293 = "<PKServicePersonality: 0x28298fb00; core = <[u DA59190E-D8A2-4109-8D7B-1702E03AB0BD] [com.company.appName.Keyboard(1.0.0)],[d (null)] [/private/var/containers/Bundle/Application/67892ACC-5BDA-4205-828D-4D94D6E87ABD/AppName.app/PlugIns/Keyboard.appex]>, host pid = 19293>"; 299 = "<PKServicePersonality: 0x282981700; core = <[u 61DC0533-3D02-4CE7-83C2-D698537BC6ED] [com.company.appName.Keyboard(1.0.0)],[d (null)] [/private/var/containers/Bundle/Application/67892ACC-5BDA-4205-828D-4D94D6E87ABD/AppName.app/PlugIns/Keyboard.appex]>, host pid = 299>"; }; } After switching between apps for few times, the custom keyboard would crash, common crash log is : Connection to plugin invalidated while in use. 2023-12-13 10:19:44.220973+0800 MobileNotes[36435:1892265] [lifecycle] [u 9A37D3B6-CAE5-4E5C-95FF-DA653DC080E5:m (null)] [com.companyName.appName.Keyboard(1.0.0)] Connection to plugin interrupted while in use. 2023-12-13 10:19:44.221229+0800 MobileNotes[36435:1892265] [lifecycle] [u 9A37D3B6-CAE5-4E5C-95FF-DA653DC080E5:m (null)] [com.companyName.appName.Keyboard(1.0.0)] Connection to plugin invalidated while in use. Another crash log is bit more detailed, but still not sure what it may refers to. ` 2023-12-13 10:19:44.222563+0800 MobileNotes[36435:1892256] [NSExtension] Unable to setup extension context - error: Couldn’t communicate with a helper application. 2023-12-13 10:19:44.222646+0800 MobileNotes[36435:1892256] [NSExtension] Async Begin using internal completion handler called multiple times. Due to error after initial completion: Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named com.company.appName.Keyboard.apple-extension-service" UserInfo={NSDebugDescription=connection to service named com.company.appName.Keyboard-extension-service} Program ended with exit code: 9`

I have a UITextField and set its text format(font/color/underline) by UITextField.attributedText. However, when I clear the text than input text again, the format is changed. It seems the behavior of attributedText is reset by system after clearing the text. Is this a bug or can we have some workaround to keep the consistent format after clearing the text? The code snippet is like below: let textField = UITextField(frame: CGRectMake(0, 0, 200, 60)) let fontColor = .red let attrText = NSMutableAttributedString(string: "normal text") let range = NSRange(location: 0, length: attrText.length) attrText.addAttribute(.font, value: UIFont.systemFont(ofSize: 14), range: range) attrText.addAttribute(.foregroundColor, value: fontColor, range: range) attrText.addAttribute(.underlineColor, value: fontColor, range: range) attrText.addAttribute(.underlineStyle, value: NSUnderlineStyle.single.rawValue, range: range) textField.attributedText = attrText

Our app has iOS deployment target as 13. We have used showsExpansionTextWhenTruncated property and is available to iOS 15+. Unfortunately we have used showsExpansionTextWhenTruncated property without if #available(iOS 15, *) and never was failed the build. However, there were many crashes because of that. Should UIKit implement @avaiable in showsExpansionTextWhenTruncated property?

Is there any solution for that

I read in Xcode 15.2 release notes that @IBDesignable and @Inspectable are deprecated and will disappear in a future release. After the abandon of WatchKit and its storyboard, replaced by SwiftUI, does it mean storyboards (and consequently UIKit) will progressively disappear, leaving developers alone with SwiftUI to design apps (IMHO, inadequate to design complex UI: for instance, I always struggle to position precisely objects for all devices sizes as we miss constraints manager in SwiftUI) ? For sure, IBDesignable is (was) whimsical, but a very useful tool to design sophisticated UI. Replacing by #Preview does not make it. I also understand that Xcode is a very complex piece of code and that maintaining and evolving some tools (as IBDesignable) requires effort. But isn't it what we expect from Apple ? To provide us with the best tools and keep on the promise of WYSIWYG environments, all along ? Is it only me or do others share this view ?

Environment: iOS 15.7.5 Device: iPhone 7 Problem: When collectionview cell textview is in edit mode and keyboard is shown - it bounces up the textview position causing overlaps. Video attached. The issue only occurs on iOS 15 version. It works well in iOS 16, 17 version. The issue occurs when Selected keyboard language is other than English. In ViewController i am updating collectionViewBottomConstraint when keyboard is up or down to enable scroll to the end of collectionview when keyboard is shown. disposable += NotificationCenter.default.reactive .notifications(forName: UIResponder.keyboardWillShowNotification) .take(duringLifetimeOf: self) .observeValues { [weak self] notification in guard let self else { return } let keyboardInfo = notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] guard var height = (keyboardInfo as? NSValue)?.cgRectValue.height else { OALogInfo("[SetLocationInfo][VC] height is nil") return } height -= self.view.safeAreaInsets.bottom self.collectionViewBottomConstraint.constant = -height self.collectionViewBottomConstraint.isActive = true } disposable += NotificationCenter.default.reactive .notifications(forName: UIResponder.keyboardWillHideNotification) .take(duringLifetimeOf: self) .observeValues { [weak self] notification in guard let self else { return } self.collectionViewBottomConstraint.constant = 0 self.collectionViewBottomConstraint.isActive = true }

I'm trying to add rotation functionality to the PKCanvasView, so that rotation gesture rotates the drawing, I want it to be working together with zoom gesture too, which is already implemented in the PKCanvasView. Rotation works reasonably fine when rotation and zoom can't be performed simultaneously. The moment I enable simultaneous zoom+rotation performance of rotation gets noticably bad. Visually it looks like rotation only happens on noticable angles like 10,20,30.. degrees which looks choppy. Zoom at the same time looks smooth as before. I'm trying to understand why and how to fix this. The rotation gesture handler is here: @objc func handleRotation(_ gesture: UIRotationGestureRecognizer) { guard let curView = gesture.view as? PKCanvasView else {return} if gesture.state == .began || gesture.state == .changed { let rotation = gesture.rotation let gestureCenter = gesture.location(in: curView) let center = CGPoint(x: gestureCenter.x / curView.zoomScale, y: gestureCenter.y / curView.zoomScale) let finalTransform = CGAffineTransform(translationX: -center.x, y: -center.y) .concatenating(CGAffineTransform(rotationAngle: rotation)) .concatenating(CGAffineTransform(translationX: center.x, y: center.y)) curView.drawing.transform(using: finalTransform) gesture.rotation = 0 } } which just constructs rotation matrix around rotation gesture center and calls curView.drawing.transform(using: finalTransform). Rotation matrix is correct I think because without simultaneous zoom+rotation it rotates everything as intended and smoothly under any zoom. (Just for clarity: in the rotation handler the matrix does only the rotation, zoom is done in pinch gesture handler implemented by the PKCanvasView. The zoomScale is used in estimations only to figure out the content coodrinate). The handleRotation method is set as let rotationGestureRecognizer = UIRotationGestureRecognizer(target: self, action: #selector(handleRotation)) rotationGestureRecognizer.delegate = self canvasView.addGestureRecognizer(rotationGestureRecognizer) The simultaneous handling of zoom+rotation I enable with this code: func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool { return true } What I've tried: Tried to nable simultaneous recognition only for zoom+rotation (without the pan gesture and possible others), the effect is the same. For example rotation+pan work smoothly together. I've verified that the gesture handler is called very often, every 8-16 milliseconds (rotation matrix creation and curView.drawing.transform(using: finalTransform) is included in this time period) which should be enough for visually smooth rotation. Other observations: When zoom and rotation both are enabled the rotation sometimes gets completely stuck, zoom and pinch is responsive but rotation is not happening visually. Only when I release fingers from the screen the rotation unstucks and content is rotated as if it didn't stuck at all. During the "stuck" period the rotation handler is called with the same frequency it's just not being visually reflected. Other thoughts: It kind of looks like the tranformation I set in the rotation handler gets overwritten by transformation from the zoom handler. But pan+rotation works fine together which confuses this theory.

is there anybody using UIConfigurationStateCustomKey to manage custom state for cells? I want to know if that would be possible to update from the collection view, it’s like UICollectionView.select(indexPath) seems like there is no way for this though. currently UICollectionView (UITableView) can manage is-selected for cells. but provided official property are only available. if we need something another custom properties that describes the cell’s state, we might need make state manager for cells. I was wondering how UIConfigurationStateCustomKey works for us for such case. According to the documentation, we can update the custom state from only visible cell. so we can not update currently hidden cell’s state. https://developer.apple.com/documentation/uikit/uiconfigurationstatecustomkey

In iOS 17, whenever I change the height of a UIHostingController in a animation block, the root SwiftUI.View ignores it: class TestAnimationController: UIViewController { var heightConstraint: NSLayoutConstraint! // a basic trigger override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) { super.touchesEnded(touches, with: event) heightConstraint.constant = heightConstraint.constant == 300 ? 100 : 300 UIView.animate(withDuration: 1.0) { self.view.layoutIfNeeded() } } override func viewDidLoad() { super.viewDidLoad() let content = UIHostingController(rootView: Color.red) addChild(content) view.addSubview(content.view) content.view.translatesAutoresizingMaskIntoConstraints = false heightConstraint = contentView.heightAnchor.constraint(equalToConstant: 100) heightConstraint.isActive = true contentView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true contentView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true contentView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true content.didMove(toParent: self) } } The result is terrible: It was not the case in iOS 14.5: Does someone have a workaround?

Hi Folks, I am reaching out for an iOS A11y color contrast issue, which I have also fired a bug report 12525894 but does not get any reply. The UIAlertAction in destructive style has a poor color contrast ratio of less than 4.5: 1 between text color and background color. This applies to any system/third party app which uses UIAlertViewController from UIKit and Alert from SwiftUI (Take the system Photos app as an example). Given that the "titleTextColor" property from UIAlertAction class is private, developers have no ways to modify the alert action to make it WCAG compatible. Here is an example of the Photo app alert. The text "Delete Photo" (#EB4E3D) should have a contrast ratio of at least 4.5 to 1 against its background(#EAEBE7) to comply to the Web Content Accessibility Guidelines (WCAG). Actual result: The text "Delete Photo" (#EB4E3D) has a contrast ratio of 3.08 to 1 against its background(#EAEBE7), which does not match 4.5:1 Web Content Accessibility Guidelines (WCAG).

Hi, I'm working on a View Controller where the Navigation Controller's UIBarButtonItems, composed of SF Symbol images and/or System Items, should change their tint color based on the current Navigation Controller scroll edge or default appearance. let buttonAppearance: UIBarButtonItemAppearance = .init(style: .plain) buttonAppearance.normal.titleTextAttributes = [.foregroundColor: color] standardAppearance.buttonAppearance = buttonAppearance I've used UIBarButtonItemAppearance titleTextAttributes to successfully change a UIButton's label text color, but I wasn't able to find a supported method under the UIAppearance API to do the same update to images. I'd highly appreciate clarification on whether or not it is supported and, if not, what could be some alternatives. Specs: iOS 16+ Thanks!

Related APIs: +[UIImage imageNamed:] +[UIImage imageNamed:inBundle:compatibleWithTraitCollection:] When there is only a color set with the name (no image set provided), reading the image with the above-mentioned APIs throws an exception: 2023-12-19 19:30:34.008701+0800 ***[57410:578064] *** Assertion failure in -[_UIImageCGImageContent initWithCGImageSource:CGImage:scale:], _UIImageContent.m:666 2023-12-19 19:30:34.031207+0800 ***[57410:578064] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Need an imageRef' Even when wrapped in a try/catch block, it still crashes due to a lock issue after calling the related API twice. Here is an example code snippet: UIImage *image; for (NSInteger i=0; i<10; i++) { @try { image = [UIImage imageNamed:@"sample"]; //image = [UIImage imageNamed:@"sample" inBundle:[NSBundle mainBundle] compatibleWithTraitCollection:nil]; } @catch (NSException *exception) { } } The crash backtrace is as follows: #0 0x0000000102b12214 in _os_unfair_lock_recursive_abort () #1 0x0000000102b0da50 in _os_unfair_lock_lock_slow () #2 0x000000010ab07624 in -[UIImageAsset imageWithConfiguration:] () #3 0x000000010b2f4634 in -[_UIAssetManager imageNamed:configuration:] () #4 0x000000010aaf2394 in +[UIImage imageNamed:inBundle:withConfiguration:] () #5 0x000000010aaf2200 in +[UIImage imageNamed:inBundle:compatibleWithTraitCollection:] () #6 0x0000000105442154 in +[UIImageAccessibility imageNamed:inBundle:compatibleWithTraitCollection:] () It seems that the color set is being treated as an imageRef in this image reading process. It's a bug of UIKit?

i’ve seen evidence that UIViewController has logic to prevent its dealloc/deinit methods from running on a background thread. what seems to occur is that, if the last strong reference to a UIVC is zeroed off the main thread, then the VC is logically marked as ‘deallocating’, but actual invocation of dealloc/deinit is enqueued to the main queue. during the window of time between the beginning and end of this asynchronous deallocation, some strange issues can occur. in particular, if the deallocating VC is a parent view controller, then its children can still access it via their parent property. despite this property being marked as weak, a non-nil parent VC reference will be returned. if a weak reference is attempted to be stored to the parent, you get a runtime crash immediately to the effect of: Cannot form weak reference to instance (0x1234) of class <some-UIVC-sublass>... surprisingly, if you load the reference via the objc runtime's objc_loadWeak method, you'll get nil, but no crash. unsurprisingly, if a strong reference to the deallocating parent is stored and persists past its dealloc invocation, you’ll generally end up with a segmentation violation if the reference is accessed. i imagine the UIVC source is quite complex and there are probably good reasons to try and ensure deallocation only ever occurs on the main thread, but it seems surprising that simply passing view controller variables across threads could lead to exposing unsafe references like this. is this behavior expected? assuming not, i've preemptively filed feedback FB13478946 regarding this issue. attached is some sample code that can reliably reproduce the unexpected behavior. UIKitAsyncDeallocCrashTests.swift

I have this ToastView that will animate by expanding the height from the top of the screen. All the components are created programmatically. This is the code: final class ToastView: UIView { private static let instance = createContainer() private let labelHeightOffset: CGFloat = 32 private let messageLabel: UILabel = { let label = UILabel() label.textAlignment = .center label.numberOfLines = 0 return label }() private var heightConstraint: NSLayoutConstraint! static func show(message: String) { let keyWindow = UIWindow.getKeyWindow() //extension to get the kley window show(on: keyWindow, message: message) } private static func show(on parentView: UIView? = nil, message: String) { guard let parentView = parentView ?? UIViewController.getTopViewController()?.view, instance.superview == nil, let toast = toast else { return } parentView.addSubview(instance, method: .fill) toast.messageLabel.text = message toast.messageLabel.textColor = .red toast.messageLabel.textAlignment = .center toast.messageLabel.sizeToFit() toast.show(for: 3) } private func show(for duration: TimeInterval = 0) { isHidden = false layoutIfNeeded() UIView.animate(withDuration: 0.4, animations: { let labelLineHeight = self.messageLabel.getRect(maxLine: 3).size.height //getRect is an extension func to get the rect based on the content of the label let lineSpaces = CGFloat((self.messageLabel.getLineNumber() - 1) * 2) //getLineNumber is an extension func to get the total number of lines based on the content //Get the height by the content of the label self.heightConstraint.constant = self.labelLineHeight + self.labelHeightOffset + lineSpaces self.setNeedsUpdateConstraints() self.superview?.layoutIfNeeded() }, completion: { _ in self.hide(delay: duration) }) } private func hide(delay: TimeInterval = 0) { UIView.animate(withDuration: 0.4, delay: delay, animations: { self.heightConstraint.constant = 0 self.setNeedsUpdateConstraints() self.superview?.layoutIfNeeded() }, completion: { _ in self.isHidden = true self.messageLabel.text = nil ToastView.instance.removeFromSuperview() }) } } private extension ToastView { static var toast: ToastView? { return instance.subviews[0] as? ToastView } static func createContainer() -> UIView { let container = UIView(frame: .zero) container.backgroundColor = .clear let toast = ToastView(frame: .zero) toast.backgroundColor = .white toast.addCorner(radius: 8) container.addSubview(toast) toast.layoutMessageLabel() toast.layoutToast() return container } func layoutMessageLabel() { addSubview(messageLabel) messageLabel.center = center messageLabel.translatesAutoresizingMaskIntoConstraints = false let constraints = [ centerYAnchor.constraint(equalTo: messageLabel.centerYAnchor), leftAnchor.constraint(equalTo: messageLabel.leftAnchor, constant: 16), rightAnchor.constraint(equalTo: messageLabel.rightAnchor, constant: 16) ] NSLayoutConstraint.activate(constraints) messageLabel.setNeedsUpdateConstraints() layoutIfNeeded() } func layoutToast() { translatesAutoresizingMaskIntoConstraints = false let topConstants: CGFloat = UIWindow.getKeyWindow()?.safeAreaInsets.top ?? 0 + 16 let topConstraint = topAnchor.constraint(equalTo: superview!.topAnchor, constant: topConstants) heightConstraint = heightAnchor.constraint(equalToConstant: 0) let constraints = [ topConstraint, heightConstraint!, leftAnchor.constraint(equalTo: superview!.leftAnchor, constant: 16), superview!.rightAnchor.constraint(equalTo: rightAnchor, constant: 16) ] NSLayoutConstraint.activate(constraints) setNeedsUpdateConstraints() superview!.layoutIfNeeded() } } The code is working fine EXCEPT for the first time it appears. It always animates from the bottom of the screen and rising above ot the top. But if you'll have a look at the code, I only animte the heightConstraint's constant value. Why is this happening? Can you help me fix this? thanks.

on iOS, when VoiceOver is running, double click the UITextView can quickly switch the cursor between the beginning and end of the text. Problem the problem is, when the text contains some NSTextAttachment, this ability has failed. Here is some code to reproduce this problem. import UIKit class ViewController: UIViewController { private var textView: UITextView? override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view. view.backgroundColor = UIColor.white textView = UITextView(frame: CGRect(x: 60, y: 220, width: 240, height: 180)) textView?.layer.borderColor = UIColor.black.cgColor textView?.layer.borderWidth = 1 textView?.font = .systemFont(ofSize: 18) view.addSubview(textView!) let button = UIButton(type: .system) button.frame = CGRect(x: 120, y: 120, width: 60, height: 60) button.setTitle("click", for: .normal) button.addTarget(self, action: #selector(self.click), for: .touchUpInside) view.addSubview(button) } @objc func click() { let emojiImage = UIImage(systemName: "iphone.circle") let lineHeight = UIFont.systemFont(ofSize: textView!.font?.pointSize ?? 0.0).lineHeight let insertedAttr = generateAttributedString(image: emojiImage, bounds: CGRect(x: 0, y: -4, width: lineHeight, height: lineHeight)) let attr = NSMutableAttributedString(attributedString: textView!.attributedText) attr.replaceCharacters(in: textView!.selectedRange, with: insertedAttr) textView!.attributedText = attr } public func generateAttributedString(image: UIImage?, bounds: CGRect) -> NSMutableAttributedString { let attachment = NSTextAttachment(data: nil, ofType: nil) attachment.bounds = bounds attachment.image = image let attrString = NSMutableAttributedString(attributedString: NSAttributedString(attachment: attachment)) attrString.addAttribute(.font, value: textView!.font!, range: NSRange(location: 0, length: attrString.length)) return attrString } }

I'm using UITextView. I set its background color to .white. Initially, the UITextView appears with a white background color. However, after I click on the UITextView, a cursor appears and the background color changes to .systemBackground. I am unable to change this background color by any means.

My Keyboard Extension has high memory usage for having UILabels with large font size. The keyboard has emojis in a single view with UICollectionView. I noticed that the bigger font size I use, the more memory usage I have. I set font size approximately to 25 and when scrolling through emojis, the memory usage goes up to 250mb. If I reduce the font size to 10, the memory usage goes down to 70mb when scrolled. The keyboard extension has 75mb memory usage. I've had my keyboard app uploaded for years and had no issues with memory usage but with recent OS update, my keyboard started crashing a lot due to memory usage and it's due to UILabel. Would it be possible to increase the memory limit or exception on the memory usage caused by the OS for large fonts stored as bitmap?

When zoom in, CATiledLayer works very well. It shows previous layer while rendering next layer. I cannot aware the rendering. When zoom out, it sucks. It leaves blank when rendering smaller scale layer. How can I solve this??? For example, when downscale, put the draw rect into main thread?

This is more of a request I hope y'all will consider. Please back port uniformAcrossSiblings to iOS 13 (or maybe just 15?) (https://developer.apple.com/documentation/uikit/nscollectionlayoutdimension/4173072-uniformacrosssiblings) It's like the iOS 9 UIStackView problem. Amazing new feature nobody can use. Has anyone else done this themselves with either custom or subclass UICollectionViewCompositionalLayout?

Having an issue with crashes on iOS 16 and iOS 17 devices. App works and will appear to operate normally. However after a while the app will crash with a EXC_BREAKPOINT on libobjc.A.dylib object_getClass. The root cause seems to be something related to UIViews/Core Animation, I think. However the root crash trigger seems to be a half a dozen different triggers from the UI on main thread. It also only triggers on release builds, or the dev builds take a lot longer to trigger to the point it's very difficult to reproduce. Here are some examples of the crashes occurring. Crashed: com.apple.main-thread 0 libobjc.A.dylib 0xe838 object_getClass + 48 1 Foundation 0x1c854 _NSKeyValueObservationInfoGetObservances + 264 2 Foundation 0x1bd1c NSKeyValueWillChangeWithPerThreadPendingNotifications + 232 3 QuartzCore 0x59408 CAAnimation_setter(CAAnimation*, unsigned int, _CAValueType, void const*) + 128 4 QuartzCore 0x749b4 -[CAAnimation setBeginTime:] + 52 5 QuartzCore 0x728b4 CA::Layer::commit_animations(CA::Transaction*, double (*)(CA::Layer*, double, void*), void (*)(CA::Layer*, CA::Render::Animation*, void*), void (*)(CA::Layer*, __CFString const*, void*), CA::Render::TimingList* (*)(CA::Layer*, void*), void*) + 740 6 QuartzCore 0x2aeac invocation function for block in CA::Context::commit_transaction(CA::Transaction*, double, double*) + 148 7 QuartzCore 0x2adb4 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 368 8 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 9 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 10 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 11 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 12 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 13 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 14 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 15 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 16 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 17 QuartzCore 0x2ad40 CA::Layer::commit_if_needed(CA::Transaction*, void (CA::Layer*, unsigned int, unsigned int) block_pointer) + 252 18 QuartzCore 0x6f548 CA::Context::commit_transaction(CA::Transaction*, double, double*) + 11192 19 QuartzCore 0x65e3c CA::Transaction::commit() + 648 20 UIKitCore 0x924cc _afterCACommitHandler + 84 21 CoreFoundation 0x3583c __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 36 22 CoreFoundation 0x34244 __CFRunLoopDoObservers + 548 23 CoreFoundation 0x33960 __CFRunLoopRun + 1028 24 CoreFoundation 0x33478 CFRunLoopRunSpecific + 608 25 GraphicsServices 0x34f8 GSEventRunModal + 164 26 UIKitCore 0x22c62c -[UIApplication _run] + 888 27 UIKitCore 0x22bc68 UIApplicationMain + 340 0 libobjc.A.dylib 0x5d94 object_getClass + 48 1 Foundation 0xadb8 _NSKeyValueObservationInfoGetObservances + 248 2 Foundation 0x3f670 NSKeyValueWillChangeWithPerThreadPendingNotifications + 232 3 QuartzCore 0xbb18 CAAnimation_setter(CAAnimation*, unsigned int, _CAValueType, void const*) + 128 4 QuartzCore 0xcc14 -[CAPropertyAnimation setKeyPath:] + 52 5 QuartzCore 0xcbc0 +[CAPropertyAnimation animationWithKeyPath:] + 36 6 UIKitCore 0xc89fb0 -[UIMorphingLabel animateGlyph:toScale:delay:] + 308 7 UIKitCore 0xc8a1fc -[UIMorphingLabel animateShowGlyph:alpha:alphaDuration:delay:] + 196 8 UIKitCore 0xc8b3f0 -[UIMorphingLabel animateSubstitutionAlignmentHunkAtIndex:] + 1068 9 UIKitCore 0x42cd84 -[UIMorphingLabel animateGlyphs] + 276 10 UIKitCore 0xa374 -[UIMorphingLabel layoutSubviews] + 368 11 UIKitCore 0x4420 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 1992 12 QuartzCore 0x9f30 CA::Layer::layout_if_needed(CA::Transaction*) + 500 13 QuartzCore 0x1d4ac CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 148 14 QuartzCore 0x2e8d8 CA::Context::commit_transaction(CA::Transaction*, double, double*) + 444 15 QuartzCore 0x5de80 CA::Transaction::commit() + 648 16 QuartzCore 0x47df0 CA::Transaction::flush_as_runloop_observer(bool) + 88 17 CoreFoundation 0x90234 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 36 18 CoreFoundation 0x1a410 __CFRunLoopDoObservers + 532 19 CoreFoundation 0x7a19c __CFRunLoopRun + 1028 20 CoreFoundation 0x7f3ec CFRunLoopRunSpecific + 612 21 GraphicsServices 0x135c GSEventRunModal + 164 22 UIKitCore 0x39cf58 -[UIApplication _run] + 888 23 UIKitCore 0x39cbbc UIApplicationMain + 340 I'm at a loss, I'm clearly doing something wrong in the UIView/Core Animation side of things. Would be very grateful for anyone who can point me in the right direction.