Swift 6

I have the following code: extension AssetGridViewController: PHPhotoLibraryChangeObserver { func photoLibraryDidChange(_ changeInstance: PHChange) { Task { @MainActor in guard let changes = changeInstance.changeDetails(for: fetchResult) else { return } fetchResult = changes.fetchResultAfterChanges } } } With Swift 6, this generates a compilation error: Main actor-isolated instance method 'photoLibraryDidChange' cannot be used to satisfy nonisolated protocol requirement. The error includes to fix-it suggestions: Adding nonisolated to the function (nonisolated func photoLibraryDidChange(_ changeInstance: PHChange)) Adding @preconcurrency to the protocol conformance (extension AssetGridViewController: @preconcurrency PHPhotoLibraryChangeObserver {) Both options generate a runtime error: EXC_BREAKPOINT (code=1, subcode=0x105b7c400). For context, AssetGridViewController is a regular UIViewController. Any ideas on how to fix this?

I am trying to port SceneKit projects to Swift 6, and I just can't figure out how that's possible. I even start thinking SceneKit and Swift 6 concurrency just don't match together, and SceneKit projects should - hopefully for the time being only - stick to Swift 5. The SCNSceneRendererDelegate methods are called in the SceneKit Thread. If the delegate is a ViewController: class GameViewController: UIViewController { let aNode = SCNNode() func renderer(_ renderer: any SCNSceneRenderer, updateAtTime time: TimeInterval) { aNode.position.x = 10 } } Then the compiler generates the error Main actor-isolated instance method 'renderer(_:updateAtTime:)' cannot be used to satisfy nonisolated protocol requirement Which is fully understandable. The compiler even tells you those methods can't be used for protocol conformance, unless: Conformance is declare as @preconcurrency SCNSceneRendererDelegate like this: class GameViewController: UIViewController, @preconcurrency SCNSceneRendererDelegate {

I took one of my apps and have gone through the process of making it compatible with Swift 6. I started with Swift 5 and Complete Concurrency Checking and eliminated every warning. I flipped the switch to Swift 6 and I have no compile errors and no warnings. I also created a ModelActor and created async functions to fetch, delete, get an object's persistentID and save model objects. My SwiftData model has a notes property and the user can update or add onto the notes and resave the model object. The app crashes when I save the changes using an explicit save operation. However, the next time the app is launched, the changes did propagate. If I do not use the explicit save operation, the system does not auto-save and does not crash. When I switched back to Swift 5 and tried it out, I was able to save without a crash. I did need to use an explicit save operation though. However, I am now getting 3 warnings like the following. Type 'ReferenceWritableKeyPath' does not conform to

Hi team, We're using CocoaPods in our project and we noticed the compiler fails to build certain targets saying it's Missing required module 'x' when trying to build them in Swift 6: We realized the modules the compiler is complaining about are pod dependencies required by the other target dependencies, and that this error will only appear when building with Swift 6 unless such dependencies are described on the Podfile as direct dependencies of the target, or we include them in the framework search paths. For example, the error in the image above will show if module 'X' import 'Y' and 'Y' imports 'CocoaLumberJack' and we don't specify a direct dependency between 'X' and 'CocoaLumberJack'. Regardless of the fact that we can manually add the missing module location to the target search paths, we'd like to understand why we're facing this issue in the first place, what changed between Swift 5 and Swift 6 that's requiring us now to explicitly describe these dependencies. I'd ap

I have the following TaskExecutor code in Swift 6 and is getting the following error: //Error Passing closure as a sending parameter risks causing data races between main actor-isolated code and concurrent execution of the closure. May I know what is the best way to approach this? This is the default code generated by Xcode when creating a Vision Pro App using Metal as the Immersive Renderer. Renderer @MainActor static func startRenderLoop(_ layerRenderer: LayerRenderer, appModel: AppModel) { Task(executorPreference: RendererTaskExecutor.shared) { //Error let renderer = Renderer(layerRenderer, appModel: appModel) await renderer.startARSession() await renderer.renderLoop() } } final class RendererTaskExecutor: TaskExecutor { private let queue = DispatchQueue(label: RenderThreadQueue, qos: .userInteractive) func enqueue(_ job: UnownedJob) { queue.async { job.runSynchronously(on: self.asUnownedSerialExecutor()) } } func asUnownedSerialExecutor() -> UnownedTaskExecutor { return UnownedTaskExecutor(ord

Hi, In the WWDC25 session Elevate an app with Swift concurrency (timestamps: 8:04 and later), the StickerViewModel is shown annotated with @Observable but not @MainActor. The narration mentions that updates happen on the main thread, but that guarantee is left implicit in the calling code. In Swift 6, though, one of the major benefits is stronger compiler enforcement against data races and isolation rules. If a view model were also annotated with @MainActor, then the compiler could enforce that observable state is only updated on the main actor, preventing accidental background mutations or updates that can cause data races between nonisolated and main actor-isolated uses. Since @Observable already signals that state changes are intended to be observed (and in practice, usually by views), it seems natural that such types should also be main-actor isolated. Otherwise, we’re left with an implicit expectation that updates will always come from the main thread, but without the compiler’s help in

Hey all! in my personal quest to make future proof apps moving to Swift 6, one of my app has a problem when setting an artwork image in MPNowPlayingInfoCenter Here's what I'm using to set the metadata func setMetadata(title: String? = nil, artist: String? = nil, artwork: String? = nil) async throws { let defaultArtwork = UIImage(named: logo)! var nowPlayingInfo = [ MPMediaItemPropertyTitle: title ?? ***, MPMediaItemPropertyArtist: artist ?? ***, MPMediaItemPropertyArtwork: MPMediaItemArtwork(boundsSize: defaultArtwork.size) { _ in defaultArtwork } ] as [String: Any] if let artwork = artwork { guard let url = URL(string: artwork) else { return } let (data, response) = try await URLSession.shared.data(from: url) guard (response as? HTTPURLResponse)?.statusCode == 200 else { return } guard let image = UIImage(data: data) else { return } nowPlayingInfo[MPMediaItemPropertyArtwork] = MPMediaItemArtwork(boundsSize: image.size) { _ in image } } MPNowPlayingInfoCenter.default().nowPlayingInfo = nowPlayingInfo

Here is a code snippet about AVPlayer. avPlayer.addPeriodicTimeObserver(forInterval: CMTime(value: 1, timescale: 60), queue: .main) { [weak self] _ in // Call main actor-isolated instance methods } Xcode shows warnings that Call to main actor-isolated instance method '***' in a synchronous nonisolated context; this is an error in the Swift 6 language mode. How can I fix this? avPlayer.addPeriodicTimeObserver(forInterval: CMTime(value: 1, timescale: 60), queue: .main) { [weak self] _ in Task { @MainActor in // Call main actor-isolated instance methods } } Can I use this solution above? But it seems switching actors frequently can slow down performance.

I'm trying to switch to UIKit's document lifecycle due to serious bugs with SwiftUI's version. However I'm noticing the template project from Xcode isn't compatible with Swift 6 (I already migrated my app to Swift 6.). To reproduce: File -> New -> Project Select Document App under iOS Set Interface: UIKit In Build Settings, change Swift Language Version to Swift 6 Run app Tap Create Document Observe: crash in _dispatch_assert_queue_fail Does anyone know of a work around other than downgrading to Swift 5?

I have the following var in an @Observable class: var displayResult: String { if let currentResult = currentResult, let decimalResult = Decimal(string: currentResult) { let result = decimalResult.formatForDisplay() UIAccessibility.post(notification: .announcement, argument: Current result (result)) return result } else { return 0 } } The UIAccessiblity.post gives me this warning: Reference to static property 'announcement' is not concurrency-safe because it involves shared mutable state; this is an error in Swift 6 How can I avoid this?

I'm calling a method with the context as parameter, within the context's perform block – is this really not legal in Swift 6? actor MyActor { func bar(context: NSManagedObjectContext) { /* some code */ } func foo(context: NSManagedObjectContext) { context.performAndWait { self.bar(context: context) // WARN: Sending 'context' risks causing data races; this is an error in the Swift 6 language mode // 'self'-isolated 'context' is captured by a actor-isolated closure. actor-isolated uses in closure may race against later nonisolated uses // Access can happen concurrently } } } The warning appears when I call a method with a context parameter, within the performAndWait-block. Background: In my app I have methods that takes in API data, and I need to call the same methods from multiple places with the same context to store it, and I do not want to copy paste the code and have hundreds of lines of duplicate code. Is there a well-known this is how you should do it for situations like this? This is r

I'm struggling to convert Swift 5 to Swift 6. As advised in doc, I first turned strict concurrency ON. I got no error. Then, selected swift6… and problems pop up. I have a UIViewController with IBOutlets: eg a TextField. computed var eg duree func using UNNotification: func userNotificationCenter I get the following error in the declaration line of the func userNotificationCenter: Main actor-isolated instance method 'userNotificationCenter(_:didReceive:withCompletionHandler:)' cannot be used to satisfy nonisolated requirement from protocol 'UNUserNotificationCenterDelegate' So, I declared the func as non isolated. This func calls another func func2, which I had also to declare non isolated. Then I get error on the computed var used in func2 Main actor-isolated property 'duree' can not be referenced from a nonisolated context So I declared duree as nonsilated(unsafe). Now comes the tricky part. The computed var references the IBOutlet dureeField if dureeField.text == X leading to the error Ma

Hi, We have recently encountered a problem running our App on iPads with A9, A10 chipset. Since recently we have migrated our Network module to swift 6 our app has stoped working on these devices. Anyone else has noticed that too or if someone know why that is happening only for iPads with specific hardware?

Hi, I'm updating our app to use Xcode 16 and Swift 6 language mode. I'm stuck on updating our live activity code. I looked at the Emoji Rangers sample project and after switching it to Swft 6 mode, it has the exact same errors as our project. The main problem seems to be that Activity is not Sendable, which prevents us from passing it to child tasks to await things like activityStateUpdates and contentUpdates (those are also not Sendable). Is there any guidance on this? Updated sample code? Another project?

I'm fairly new to Swift, so I'm unsure as to what's going wrong with my code and how to fix it. After switching to Swift 6, the view I have with requestReview throws: Cannot form key path to main actor-isolated property 'requestReview' As I understand it, this is potentially due to the changes made to @MainActor. However, I am unsure how to go about fixing this error.