Hi, I have a very simple program (see below) with some Views in an HStack, which is within a ScrollView. This works fine on iOS, but on macOS nothing scrolls. Am I missing something? Shouldn't it just scroll? import SwiftUI struct ContentView: View { 	var body: some View { 		ScrollView(.horizontal, showsIndicators: true) { 			HStack { 				ItemView(n: 1) 				ItemView(n: 2) 				ItemView(n: 3) 				ItemView(n: 4) 				ItemView(n: 5) 			} 		} 		.frame(minWidth: 350, maxWidth: 800, minHeight: 250, maxHeight: 250, alignment: .center) 	} } struct ContentView_Previews: PreviewProvider { 	static var previews: some View { 		ContentView() 	} } struct ItemView: View { 	var n: Int 	 	var body: some View { 		Rectangle() 			.frame(width: 300, height: 200) 			.overlay(Text("\(n)").foregroundColor(.white)) 	} }

I am getting a strange crash (see call stack in attached screenshot). I am looking for ideas/hints how to track down what the issue is?

Hi, when using URL session nested in a few async/await calls I get a crash in swift_getObjectType (sometimes in processDefaultActor). Any ideas what could be causing this or hints how to debug/where to look? For a (contrived - because it was extracted from a larger project) example please see below (see "crashes here" comment for the last call before the crash). Thanks for any hints in advance! Cheers, Michael // Crash on: Xcode Version 13.0 beta (13A5155e), macOS 11.4 (20F71), on iPhone Simulator import CoreData import SwiftUI struct ContentView: View { @StateObject var dataCoordinator: DataCoordinator = .init() var body: some View { Button { print("GO") async { try await dataCoordinator.api.getSomething() } } label: { Label("Go", systemImage: "figure.walk") } .buttonStyle(.bordered) } } struct ContentView_Previews: PreviewProvider { static var previews: some View { ContentView().environment(\.managedObjectContext, PersistenceController.preview.container.viewContext) } } // MARK: - Test coding - class DataCoordinator: ObservableObject { let api: API = .init() func refreshSomething() async throws { try await api.getSomething() } } // MARK: - class API { var session: URLSession = .init(configuration: .ephemeral) func getSomething() async throws { let url = URL(string: "https://www.heise.de")! let request = URLRequest(url: url) let (data, response) = try await _failsafe(request: request) print("\(response)") } private func _failsafe(request: URLRequest) async throws -> (Data, URLResponse) { do { var (data, response) = try await session.data(for: request) let httpResponse = response as! HTTPURLResponse var recovered = false if httpResponse.allHeaderFields["dsfsfsdsfds"] == nil { let login = LoginAsync() await login.login(session: session) recovered = true } if recovered { let req2 = URLRequest(url: URL(string: "https://www.heise.de")!) print("right before crash") try await session.data(for: req2) // crashes here with EXC_BAD_ACCESS print("right after crash ;-)") } return (data, response) } catch { print("\(error)") throw error } } } // MARK: - actor LoginAsync { func login(session: URLSession) async { let url = URL(string: "https://www.google.com")! let request = URLRequest(url: url) do { let (data, response) = try await session.data(for: request) } catch { print("\(error)") } } }

Hi, is there a way that an actor can have a @MainActor @Published annotated property which is then consumed by a SwiftUI View "as usual"? Currently this: @Published @MainActor public private(set) var state: State = .initial gives me the following error when trying to access it from with a SwiftUI View: "Actor-isolated property '$state' can only be referenced from inside the actor" I guess I understand where the error is coming from, but I wonder if there's a way to publish properties from actors and be able to make sure they are updated on the main thread by annotating them with @MainActor.

Hi, since the Xcode 13 beta 5 I am seeing crashes in _os_semaphore_dispose.cold.* when running in the iOS simulator. This happens in different apps under various conditions, so I can pin it down to something specific. Is anybody else having similar issues? Stack of the crashing thread looks like this: Disassembly looks like this: Thanks for any feedback. Cheers, Michael

Hi, I am using a child NSManagedContext trying to isolate changes to a NSManagedObject from changes done to the same object in the parent NSManagedObjectContext. This works fine for normal properties, but any changes to relationships performed on the object in the parent context will show up immediately in the child object as well. Is this the intended behavior? If yes is there a way to create an "isolated" version of an NSManagedObject? Thanks in advance for any hints! Cheers, Michael

Hi, having the concurrency checks (-Xfrontend -warn-concurrency -Xfrontend -enable-actor-data-race-checks-Xfrontend -warn-concurrency -Xfrontend -enable-actor-data-race-checks) enabled I always get this warning, when trying to access/use an actor in a SwiftUI .task: "Cannot use parameter 'self' with a non-sendable type 'ContentView' from concurrently-executed code". What would be a correct implementation? Here's a minimal code-sample which produces this warning: import SwiftUI struct ContentView: View { @State var someVar = 5 var a1 = A1() var body: some View { Text("Hello, world!") .padding() .task { await a1.doSomething() } } } public actor A1 { func doSomething() { print("Hello") } }

Hi, I have a strange case involving sheets, which I think it's a bug, but then again I might be missing something. Using the following code: import SwiftUI enum WhichSheet: String { 	case one, two, three, none } struct ContentView: View { 	@State private var _showSheet = false 	@State private var _whichSheet: WhichSheet = .none 		var body: some View { 			VStack(spacing: 8) { 					Button("One Sheet", action: { self._whichSheet = .one; self._showSheet = true}) 					Button("Two Sheet", action: { self._whichSheet = .two; self._showSheet = true}) 					Button("Three Sheet", action: { self._whichSheet = .three; self._showSheet = true}) 			} 				.sheet(isPresented: $_showSheet, content: { 				Text("whichSheet = \(_whichSheet.rawValue)") 			}) 		} } struct ContentView_Previews: PreviewProvider { 		static var previews: some View { 			ContentView() 		} } I would assume that, depending on which button is pressed, I would say a sheet with the text "whichSheet = one" or "whichSheet = two" etc. But no matter which button is pressed first the text on the sheet is always "whichSheet = none". Only if you choose a different button the second (or third, or ...) time the correct text is being displayed. Bug or am I missing something really obvious? (Test using an iOS 14 / 14.2 project with Xcode 12 / 12.2 beta) Cheers, Michael

Hi, it seems that a @State variable in a View will not update (initialize to the new value) on subsequent calls to the Views .init method. In the example below (tested on macOS) the Text("internal: \(_internalNumber)") still shows 41, even after 1s is over and number was set to 42 (in the .task). TestView.init runs as expected and _internalNumber shows the correct value there, but in the body method (on the redraw) _internalNumber still has the old value. This is not how it should be, right? import SwiftUI struct ContentView: View { @State private var number = 41 var body: some View { VStack { TestView(number: number) .fixedSize() } .task { try! await Task.sleep(nanoseconds: 1_000_000_000) await MainActor.run { print("adjusting") number = 42 } } } } //////////////////////// // MARK: - TestView - public struct TestView: View { public init(number: Int) { self.number = number __internalNumber = .init(initialValue: number) print("Init number: \(self.number)") print("Init _internalNumber: \(_internalNumber)") } var number: Int @State private var _internalNumber: Int public var body: some View { VStack(alignment: .leading) { Text("number: \(number)") Text("internal: \(_internalNumber)") } .debugAction { Self._printChanges() print("number: \(number)") print("_internalNumber: \(_internalNumber)") } } } // MARK: - debugAction extension View { func debugAction(_ closure: () -> Void) -> Self { closure() return self } }

Hi, I want to import GPX files into my iOS App. It works fine in the simulator using: .fileImporter(isPresented: $showFileImporter, allowedContentTypes: [UTType(filenameExtension: "gpx")!, UTType(filenameExtension: "GPX")!], allowsMultipleSelection: true) But running the app on an actual device (iOS 15 Beta 6), I am not allowed to select any of the GPX files. The strange thing is, that if I am using "jpg" instead of "gpx" I can select "jpg" files just fine. So it seems, that it has to do something with the "GPX" type being 'custom'. Any idea/hint what I am missing? Thank you! Michael

Hi, when generating thumbnails I sometimes see the error "QLThumbnailErrorDomain Code=110". This happens to files which can be processed when trying again, so it is not an issue with the files in general. I could not find an error with that code here. Any ideas where to look and/or what causes this? Thanks, Michael

Hi! When using the Sample "NavigationCookbook" in the two column layout, the selection in the first column is not remembered, when navigating to the Home Screen and back. This behaviour can be reproduced by starting the app on the iPad or simulator, selecting for example "Pancake" and then navigating to the home screen and back into the navigation. Sometimes this (the navigation to/back from the home screen) has to be done twice, to lose the selection. In the console log you can see the message "Update NavigationAuthority bound path tried to update multiple times per frame." appearing. Not sure if this has something todo with the selection being lost. This is on iOS 16.4.1 not sure if the behaviour before was different. Anybody experiences the same behaviour? Bug in SwiftUI or in the sample app? Cheers, Michael

Hi, I encountered the issue, that unless an inverse relationship is modelled, the relationship is not persisted. This can be reproduced with the sample code below: Press the "Add Person" button twice Then press the "Add group" button You now can see that the group has to member, but once you restart the app the members a gone. Once an inverse relationship is added (see commented code) the relationships are persisted. Any idea if this is intended behaviour? import SwiftData import SwiftUI // MARK: - Person - @Model class Person { var name: String // uncomment to make it work @Relationship(.nullify) var group: Group? init(name: String) { self.name = name } } // MARK: - Group - @Model class Group { var name: String // uncomment to make it work @Relationship(.nullify, inverse: \Person.group) public var members: [Person] @Relationship(.nullify) public var members: [Person] // comment to make it work init(name: String) { self.name = name } } // MARK: - SD_PrototypingApp - @main struct SD_PrototypingApp: App { var body: some Scene { WindowGroup { ContentView() } .modelContainer(for: [Person.self, Group.self]) } } // MARK: - ContentView - struct ContentView: View { @Environment(\.modelContext) private var modelContext @Query private var groups: [Group] @Query private var persons: [Person] var body: some View { VStack { ForEach(groups) { group in Text("\(group.name): \(group.members.count)") } ForEach(persons) { person in Text("Person: \(person.name)") } Button { assert(persons.isEmpty == false) if groups.isEmpty { let group = Group(name: "Group A") group.members = persons modelContext.insert(group) try! modelContext.save() } } label: { Text("Add a group") } .disabled(!groups.isEmpty || persons.isEmpty) Button { let person = Person(name: "Person \(Int.random(in: 0 ... 1_000_000))") modelContext.insert(person) } label: { Text("Add Person") } } } }

Hi, given this model: @Model class OnlyName { var name: String init(name: String) { self.name = name } } I would assume that I could write a predicate like this: #Predicate<OnlyName> { $0.name == other.name }, where other is also an instance of OnlyName for example returned by an earlier fetch. Unfortunately this results in the following compiler errors: Initializer 'init(_:)' requires that 'OnlyName' conform to 'Encodable' Initializer 'init(_:)' requires that 'OnlyName' conform to 'Decodable' Any idea if this is a bug in SwiftData or if I am missing something? Cheers, Michael

Hi, in the session the following is mentioned: If a trip already exists with that name, then the persistent back end will update to the latest values. This is called an upsert. An upsert starts as an insert. If the insert collides with existing data, it becomes an update and updates the properties of the existing data. Nevertheless, if I have a unique constraint on an (String) attribute and try to insert the same again, I end up in the debugger in the generated getter of the attribute: @Attribute(.unique) public var name: String { get { _$observationRegistrar.access(self, keyPath: \.name) return self.getValue(for: \.name) // <- here } EXC_BREAKPOINT (code=1, subcode=0x1a8d6b724) Am I missing something? If this is expected behaviour, how should I prevent this crash (other than checking for uniqueness before every insert)? Thank you! Cheers, Michael