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A Summary of the WWDC25 Group Lab - UI Frameworks
At WWDC25 we launched a new type of Lab event for the developer community - Group Labs. A Group Lab is a panel Q&A designed for a large audience of developers. Group Labs are a unique opportunity for the community to submit questions directly to a panel of Apple engineers and designers. Here are the highlights from the WWDC25 Group Lab for UI Frameworks. How would you recommend developers start adopting the new design? Start by focusing on the foundational structural elements of your application, working from the "top down" or "bottom up" based on your application's hierarchy. These structural changes, like edge-to-edge content and updated navigation and controls, often require corresponding code modifications. As a first step, recompile your application with the new SDK to see what updates are automatically applied, especially if you've been using standard controls. Then, carefully analyze where the new design elements can be applied to your UI, paying particular attention to custom controls or UI that could benefit from a refresh. Address the large structural items first then focus on smaller details is recommended. Will we need to migrate our UI code to Swift and SwiftUI to adopt the new design? No, you will not need to migrate your UI code to Swift and SwiftUI to adopt the new design. The UI frameworks fully support the new design, allowing you to migrate your app with as little effort as possible, especially if you've been using standard controls. The goal is to make it easy to adopt the new design, regardless of your current UI framework, to achieve a cohesive look across the operating system. What was the reason for choosing Liquid Glass over frosted glass, as used in visionOS? The choice of Liquid Glass was driven by the desire to bring content to life. The see-through nature of Liquid Glass enhances this effect. The appearance of Liquid Glass adapts based on its size; larger glass elements look more frosted, which aligns with the design of visionOS, where everything feels larger and benefits from the frosted look. What are best practices for apps that use customized navigation bars? The new design emphasizes behavior and transitions as much as static appearance. Consider whether you truly need a custom navigation bar, or if the system-provided controls can meet your needs. Explore new APIs for subtitles and custom views in navigation bars, designed to support common use cases. If you still require a custom solution, ensure you're respecting safe areas using APIs like SwiftUI's safeAreaInset. When working with Liquid Glass, group related buttons in shared containers to maintain design consistency. Finally, mark glass containers as interactive. For branding, instead of coloring the navigation bar directly, consider incorporating branding colors into the content area behind the Liquid Glass controls. This creates a dynamic effect where the color is visible through the glass and moves with the content as the user scrolls. I want to know why new UI Framework APIs aren’t backward compatible, specifically in SwiftUI? It leads to code with lots of if-else statements. Existing APIs have been updated to work with the new design where possible, ensuring that apps using those APIs will adopt the new design and function on both older and newer operating systems. However, new APIs often depend on deep integration across the framework and graphics stack, making backward compatibility impractical. When using these new APIs, it's important to consider how they fit within the context of the latest OS. The use of if-else statements allows you to maintain compatibility with older systems while taking full advantage of the new APIs and design features on newer systems. If you are using new APIs, it likely means you are implementing something very specific to the new design language. Using conditional code allows you to intentionally create different code paths for the new design versus older operating systems. Prefer to use if #available where appropriate to intentionally adopt new design elements. Are there any Liquid Glass materials in iOS or macOS that are only available as part of dedicated components? Or are all those materials available through new UIKit and AppKit views? Yes, some variations of the Liquid Glass material are exclusively available through dedicated components like sliders, segmented controls, and tab bars. However, the "regular" and "clear" glass materials should satisfy most application requirements. If you encounter situations where these options are insufficient, please file feedback. If I were to create an app today, how should I design it to make it future proof using Liquid Glass? The best approach to future-proof your app is to utilize standard system controls and design your UI to align with the standard system look and feel. Using the framework-provided declarative API generally leads to easier adoption of future design changes, as you're expressing intent rather than specifying pixel-perfect visuals. Pay close attention to the design sessions offered this year, which cover the design motivation behind the Liquid Glass material and best practices for its use. Is it possible to implement your own sidebar on macOS without NSSplitViewController, but still provide the Liquid Glass appearance? While technically possible to create a custom sidebar that approximates the Liquid Glass appearance without using NSSplitViewController, it is not recommended. The system implementation of the sidebar involves significant unseen complexity, including interlayering with scroll edge effects and fullscreen behaviors. NSSplitViewController provides the necessary level of abstraction for the framework to handle these details correctly. Regarding the SceneDelagate and scene based life-cycle, I would like to confirm that AppDelegate is not going away. Also if the above is a correct understanding, is there any advice as to what should, and should not, be moved to the SceneDelegate? UIApplicationDelegate is not going away and still serves a purpose for application-level interactions with the system and managing scenes at a higher level. Move code related to your app's scene or UI into the UISceneDelegate. Remember that adopting scenes doesn't necessarily mean supporting multiple scenes; an app can be scene-based but still support only one scene. Refer to the tech note Migrating to the UIKit scene-based life cycle and the Make your UIKit app more flexible WWDC25 session for more information.
Topic: UI Frameworks SubTopic: General
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688
Jun ’25
SwiftUI Text is larger when empty
I have a simple SwiftUI Text: Text(t) .font(Font.system(size: 9)) Strangely its ideal height seems to be larger when it is empty. I initially observed this in a custom Layout container that wasn't working quite right. Eventually I looked at the height returned by v.dimensions(in:), and found that when t is non-empty the height is 11; when empty, it's 14. Subsequently I observed similar behaviour in a regular VStack container. Has anyone seen anything similar? Are there any properties that could affect this behaviour? (This is on a watch - I don't know if that matters.)
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308
Jan ’25
SwiftUI flash animation
I'm struggling to implement a flash animation in SwiftUI. Generally animations animate from one value to another. I'd like to animate from normal to the flashed state and then back to normal, each time the data shown by the view changes. The "flashed state" could be transparent, or a white background, or it could be a scale change for a pulse effect, or something. Example: struct MyView: View { let value: String; var body: some View { ZStack { Capsule() .fill(Color.green); Text(value); } }; }; Each time value changes, I'd like the colour of the capsule to quickly animate from green to white and back to green. I feel this should be easy - am I missing something? For bonus points: I'd like the Text to change to its new value at the midpoint of the animation, i.e. when the white text is invisible on the white background. I'd like to get the flash effect whenever I have a new value even if the new value is equal to the old value, if you see what I mean.
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Jan ’25
Variable modification in forEach
Hi! I'm trying to do a forEach loop on an array of objects. Here's my code : ForEach($individus) { $individu in if individu.reussite == true { individu.score -= 10 } else { individu.score = (individu.levees * 10) + 20 + individu.score } } I have an error on the code in the 'if' saying that "Type '()' cannot conform to 'View'", but I have no idea on how solving this problem.
Topic: UI Frameworks SubTopic: SwiftUI
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261
Jan ’25
iOS18 UIPinchGestureRecognizer finger change
Before ios18, when two fingers are switched to single fingers, the printing scale value will not change. When switching to two fingers again, the pinch and zoom printing scale will change. The same operation is performed after ios18, and two fingers are switched to single fingers. Switch back to two fingers, and the scale printing will not change. code here: - (void)pinchGesture:(UIPinchGestureRecognizer *)recognizer { NSSet <UIEvent*> *events = [recognizer valueForKey:@"_activeEvents"]; UIEvent *event = [events anyObject]; if (recognizer.state == UIGestureRecognizerStateBegan) { NSLog(@"---- begin finger count: %d scale: %f",event.allTouches.count,recognizer.scale); recognizer.scale = 1.0; } else if (recognizer.state == UIGestureRecognizerStateChanged) { NSLog(@"---- change finger count: %d scale: %f",event.allTouches.count,recognizer.scale); // recognizer.scale = 1.0; } log image for iOS 17.7 log image for ios18.0.2
Topic: UI Frameworks SubTopic: UIKit Tags:
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297
Jan ’25
SwiftUI Canvas Text - scale to fill rectangle
How do I draw a single line of text in a SwiftUI Canvas, scaled to fill a given rectangle? Example: Canvas { context, size in let r = CGRect(origin: CGPointZero, size: size); // Whole canvas let t = Text("Hello World"); context.draw(t, in: r); } Outside of Canvas I'd add .minimumScaleFactor(0) .lineLimit(1), and I guess set a large default font size, and I'd get the result I want. But inside Canvas, .minimumScaleFactor and .lineLimit don't seem to be available; they return some View, not Text, which can't be used in context.draw. (Is there a trick to make that work?) I have written the following to do this, but I think there must be an easier way to achieve this! Suggestions? extension GraphicsContext { mutating func draw_text_in_rect(string: String, rect: CGRect) { let text = Text(string) .font(.system(size: 25)); // The font size used here does matter, because e.g. letter spacing // varies with the font size. let resolved = resolve(text); let text_size = resolved.measure(in: CGSize(width: CGFloat.infinity, height: CGFloat.infinity)); let text_aspect = text_size.width / text_size.height; let fit_size = CGSize(width: min(rect.size.width, rect.size.height*text_aspect), height: min(rect.size.height, rect.size.width/text_aspect)); let fit_rect = CGRect(x: rect.origin.x + (rect.size.width-fit_size.width)/2, y: rect.origin.y + (rect.size.height-fit_size.height)/2, width: fit_size.width, height: fit_size.height); let scale = fit_size.width / text_size.width; // For debug: // var p = Path(); // p.addRect(fit_rect); // stroke(p, with: GraphicsContext.Shading.color(.red), lineWidth: 1); translateBy(x: fit_rect.minX, y: fit_rect.minY); scaleBy(x:scale, y:scale); draw(resolved, at: CGPointZero, anchor: UnitPoint.topLeading); transform = CGAffineTransformIdentity; } };
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371
Jan ’25
Carplay在CPNowPlayingTemplate显示图片的败,且不可点击
System: iOS 18.1.1 When connected to Carplay, after playing a song, check the playback page CPNowPlayingTemplate. This error appears on the BMW car, as shown in the picture: In our project, this is achieved using the following methods: UIImage *image1 = [UIImage imageNamed:@"imageName"];; CPNowPlayingImageButton *button1 = [[CPNowPlayingImageButton alloc] initWithImage:image1 handler:^(__kindof CPNowPlayingButton * _Nonnull action) { //do something }]; UIImage *image2 = [UIImage imageNamed:@"imageName"];; CPNowPlayingImageButton *button2 = [[CPNowPlayingImageButton alloc] initWithImage:image2 handler:^(__kindof CPNowPlayingButton * _Nonnull action) { //do something }]; NSArray<CPNowPlayingButton *> *buttons; buttons = @[button1,button2]; [[CPNowPlayingTemplate sharedTemplate] updateNowPlayingButtons:buttons]; Is there any way to solve this problem?
Topic: UI Frameworks SubTopic: UIKit Tags:
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390
Jan ’25
MVVM design and data dependency
According to the MVVM design pattern, one of my views depends on many properties in my model. Can I use logic like @published var model = MyModel()? Will there be a large performance loss? Will the UI be refreshed when other unrelated properties in the model are modified? What is the best practice in this case?
Topic: UI Frameworks SubTopic: General
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248
Jan ’25
Custom app icon on macOS
I would like to provide a way to choose an app icon as a reward for using the referral feature of the app. I found that setting the image via NSApp.applicationIconImage works, but only when the app is running, and the app icon is reset on the next launch. I also found NSDockTile plugin APIs, and that seems to be the way, but it won't be allowed on the Mac App Store. Is there really no way to do it legit way and pass the Mac App Store review? Seems to be another really strange limitation imposed.
Topic: UI Frameworks SubTopic: AppKit Tags:
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363
Feb ’25
Bug in iOS 18 with NSTimeZone and DatePicker
iOS 18 broke some functionality in my Objective-C app with regard to using the DatePicker. The key lines are as follows: datePicker.timeZone = [NSTimeZone timeZoneForSecondsFromGMT:timezoneOffset]; datePicker.date = [NSDate date]; When timezoneOffset is -29380, the value for San Francisco, the Date Picker is a whole MONTH off. It shows November instead of December. But when it is -29359, the value for Seattle, which is in the same time zone (PST), it shows the correct month. In fact, even towns surrounding San Francisco usually return the correct value. Some other cities in other time zones also cause the Date Picker to be a month off.
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Jan ’25
Why timer isn't working with button in SwiftUI
.onReceive construction isn't working with button long press gesture but tap is working, it increases count by 1. Construction should increase count every 0.5 seconds if button pressed struct Test: View { @State private var count = 0 @State private var isLongPressed = false var body: some View { VStack { Text("Count: \(count)") Button("Increase") { count += 1 print("Button tapped") } .onLongPressGesture { isLongPressed = true print("Long press started") } .onLongPressGesture(minimumDuration: 0) { isLongPressed = false print("Long press ended") } } .onReceive(Timer.publish(every: 0.5, on: .main, in: .common).autoconnect()) { _ in if isLongPressed { count += 1 print("Count increased: \(count)") } } } }
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Jan ’25
https://forums.developer.apple.com/forums/post/question
Hi everyone, I’m working on an iOS app using both UITableViewDiffableDataSource and SwiftUI, and I’m facing two separate but puzzling issues: UITableViewDiffableDataSource Not Reusing Cells on first applying after initial Snapshot. After applying first time it is working as expected from second time. SwiftUI View’s inside UITableViewCell onDisappear Not Triggering the on first changes of snapshot after initial snapshot. With normal UITableView it is working fine. Issue causing - it is causing player &amp; cells to retain memory extensively Sample gist code for reproducing with diffable (DiffableTableViewExampleViewController) and working fine without diffable (RegularTableViewExampleViewController) https://gist.github.com/SURYAKANTSHARMA/d83fa9e7e0de309e27485100ba5aed17 Any insights or suggestions for these issues would be greatly appreciated! Thanks in advance!
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226
Jan ’25
How to use .symbolVariant(.contains: )
I'm getting a weird response from Xcode in trying to use symbolVariant(.contains). I also don't understand why it demands the type cast. What am I doing wrong? Here's the code as text: import SwiftUI let Variants: [SymbolVariants] = [ .circle, .square, .fill, .rectangle, .slash, .none ] func varAvail(_ image: Image) -> [SymbolVariants] { var res: [SymbolVariants] = [] for variant in Variants { if image.symbolVariant(.contains(variant)) as! Bool { res.append(variant) } } }
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Jan ’25
App Clip show "App Clip Unavailable" only when the main app is not installed
After uploading the app to App Store Connect, Apple automatically generated a Default App Clip Link. However, the App Clip card only opens successfully if the main app is already installed on the device. If the main app is not installed, the App Clip card displays an image and the message "App Clip Unavailable" What could cause this behavior, and how do I ensure the App Clip works without requiring the main app to be installed?
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394
Feb ’25
Dynamically Update Complex UI Views in SwiftUI
I am working on a SwiftUI project where I need to dynamically update the UI by adding or removing components based on some event. The challenge is handling complex UI structures efficiently while ensuring smooth animations and state management. Example Scenario: I have a screen displaying a list of items. When a user taps an item, additional details (like a subview or expanded section) should appear dynamically. If the user taps again, the additional content should disappear. The UI should animate these changes smoothly without causing unnecessary re-renders. My Current Approach: I have tried using @State and if conditions to toggle views, like this: struct ContentView: View { @State private var showDetails = false var body: some View { VStack { Button("Toggle Details") { showDetails.toggle() } if showDetails { Text("Additional Information") .transition(.slide) // Using animation } } .animation(.easeInOut, value: showDetails) } } However, in complex UI scenarios where multiple components need to be shown/hidden dynamically, this approach is not maintainable and could cause performance issues. I need help with the below questions. Questions: State Management: Should I use @State, @Binding, or @ObservedObject for handling dynamic UI updates efficiently? Best Practices: What are the best practices for structuring SwiftUI views to handle dynamic updates without excessive re-renders? Performance Optimization: How can I prevent unnecessary recomputations when updating only specific UI sections? Animations & Transitions: What is the best way to apply animations smoothly while toggling visibility of multiple components? Advanced Approaches: Are there better techniques using @EnvironmentObject, ViewBuilder, or even GeometryReader for dynamically adjusting UI layouts? Any insights, code examples, or resources would be greatly appreciated.
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348
Jan ’25
Unrealistically high snowfall amounts being reported by WeatherKit
I filed FB16332997 about the VERY high snowfall estimates I'm seeing in WeatherKit and iOS Weather. I initially thought something was wrong with my weather app but I verified the numbers with the iOS Weather app and another third party weather app. For Atlanta last week it was saying 7.5" when it ended up being 2" (which I can live with). Two days ago it reported there could be 16" of snow in northern Florida. That's impossible! This morning it was reporting that Niceville could have 6-7" of snow, which would be significantly more than highest amount in recorded history for Florida (where snow is extremely rare). It almost makes me wonder if the liquid precipitation value is actually the snowfall amount in reality. And then that is incorrectly being converted to the snowfall amount.
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460
Jan ’25
SwiftUI Menu with NavigationLinks inside overall NavigationStack
I've read all previous posts on this topic but none seem to address what I'm seeing for iOS 16 and using NavigationStack. I'm also using an overall @EnvironmentObject for navigation state. I have a split view app. In the detail section, I have a NavigationStack surrounding the detail view. Within the detail view (MyView), there is a base view with a "+" button in the toolbar to create a new entity. That opens NewEntityView where I show a grid of buttons for the user to select a type to create a new entity before moving to NewEntityView to fill in the details for the entity. The top row of the grid of buttons takes the user straight to the NewEntityView with a NavigationLink. These work fine. The next row of buttons present a menu of sub-types and then should take the user to the NewEntityView view. These buttons do not work. Code (simplified to not have clutter): SplitViewDetailView: struct SplitViewDetailView: View { @EnvironmentObject var navigationManager: NavigationStateManager @Binding var selectedCategory: Route? var body: some View { NavigationStack(path: $navigationManager.routes) { // other irrelevant stuff MyView() } .environmentObject(navigationManager) .navigationDestination(for: Route.self) { $0 } } } MyView: struct MyView: View { @EnvironmentObject var navigationManager: NavigationStateManager var body: some View { List { // other stuff } .toolbar { ToolbarItem(placement: .navigationBarTrailing) { Button(action: {}, label: { NavigationLink(value: Route.newTypeSelect) { Image(systemName: "plus") .frame(width: 44, height: 44) } } ) } } .navigationDestination(for: Route.self) { $0 } } SelectTypeView: struct SelectTypeView: View { var body: some View { ZStack { VStack { // Top row with no subtypes HStack { ForEach (topRows, id: \.self) { type in NavigationLink(value: Route.newEntityDetails(type.rawValue)) { <-- these work Text(type) } } } HStack { ForEach (middleRow, id: \.self) { type in Menu { ForEach (subtype[type], id: \.self) { sub in NavigationLink(value: Route.newEntityDetails(sub.rawValue)) { <-- these go nowhere Text(sub) } } } label: { Text(type) } } } } } } } NavigationStateManager: class NavigationStateManager: ObservableObject { @Published var routes = [Route]() // other stuff } And Route: enum Route: Identifiable { var id: UUID { UUID() } case newTypeSelect case newEntityDetails(String) } extension Route: View { var body: some View { switch self { case .newTypeSelect: SelectTypeView() case .newEntityDetails(let type): NewEntityView(selectedType: type) } } } The menus show up fine but tapping on an item does nothing. I've attempted to wrap the menu in its own NavigationStack but that is rejected stating it is already in one defined by a parent view. I've tried making the links Buttons with destinations and those are also rejected. What is the newest/best way to present a menu with NavigationLinks? One doesn't simply wrap the menu in a NavigationView if one is using a NavigationStack?
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1.2k
Jan ’25
Unexpected Insertion of U+2004 (Space) When Using UITextView with Pinyin Input on iOS 18
I encountered an issue with UITextView on iOS 18 where, when typing Pinyin, extra Unicode characters such as U+2004 are inserted unexpectedly. This occurs when using a Chinese input method. Steps to Reproduce: 1. Set up a UITextView with a standard delegate implementation. 2. Use a Pinyin input method to type the character “ㄨ”. 3. Observe that after the character “ㄨ” is typed, extra spaces (U+2004) are inserted automatically between the characters. Code Example: class ViewController: UIViewController { @IBOutlet weak var textView: UITextView! override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view. } } extension ViewController: UITextViewDelegate { func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool { print("shouldChangeTextIn: range \(range)") print("shouldChangeTextIn: replacementText \(text)") return true } func textViewDidChange(_ textView: UITextView) { let currentText = textView.text ?? "" let unicodeValues = currentText.unicodeScalars.map { String(format: "U+%04X", $0.value) }.joined(separator: " ") print("textViewDidChange: textView.text: \(currentText)") print("textViewDidChange: Unicode Scalars: \(unicodeValues)") } } Output: shouldChangeTextIn: range {0, 0} shouldChangeTextIn: replacementText ㄨ textViewDidChange: textView.text: ㄨ textViewDidChange: Unicode Scalars: U+3128 ------------------------ shouldChangeTextIn: range {1, 0} shouldChangeTextIn: replacementText ㄨ textViewDidChange: textView.text: ㄨ ㄨ textViewDidChange: Unicode Scalars: U+3128 U+2004 U+3128 ------------------------ shouldChangeTextIn: range {3, 0} shouldChangeTextIn: replacementText ㄨ textViewDidChange: textView.text: ㄨ ㄨ ㄨ textViewDidChange: Unicode Scalars: U+3128 U+2004 U+3128 U+2004 U+3128 This issue may affect text processing, especially in cases where precise text manipulation is required, such as calculating ranges in shouldChangeTextIn.
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1k
Jan ’25
INUIHostedViewControlling ViewController's Life Cycle Events not being Called
I am implementing a new Intents UI Extension and am noticing that the viewWillDisappear, viewDidDisappear, and deinit methods are not being called on my UIViewController that implements INUIHostedViewControlling, when pressing the "Done" button and dismissing the UIViewController. This causes the memory for the UI Extension to slowly increase each time I re-run the UI Extension until it reaches the 120MB limit and crashes. Any ideas as to what's going on here and how to solve this issue? Worth noting that while the memory does continuously increase on iOS versions before iOS 17, only in 17 and later does the 120MB memory limit kick in and crash the extension.
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Feb ’25