We have been seeing a dyld loader crash when trying out the new Previews engine in Xcode 16 beta 3. Feedback filed with reproducer + diagnostics: https://feedbackassistant.apple.com/feedback/14323960 Investigation: Running nm -a on the debug dylib reveals duplicate SO entries pointing to SomeStatic.swift. One entry originates from the LibAStatic module, while the other comes from the LibBStatic module. Local workaround - 1 Providing unique file names resolves the issue. However, these files are in different modules, so ideally, this shouldn't be necessary. Our codebase is extensive, and many code-generated modules have the same file names. Therefore, renaming files to ensure uniqueness is not a simple solution for us due to various complexities. Local workaround - 2 Making these dependencies dylibs instead of static libraries also resolves the issue. However, we can't pursue this direction because a significant portion of our pre-build setup, foundations, and vendor linkages are statically linked. Note: The same flow works with "Legacy Preview Engine in Xcode 16/15" but dynamic replacement has other issues, which we are super happy that the new engine doesn't make use of. This issue is currently a blocker for us in trying out the new Previews in our project, it would be highly beneficial if this problem could be resolved soon.

== PREVIEW UPDATE ERROR: JITError ================================== | NoBuiltTargetDescriptionCouldBeFound | | translationUnit: PreviewTranslationUnit(moduleNamePrefix: "Previews_EmptyFeedRow", sourceIdentifier: file:///Users/bryananderson/Developer/JournalApp/JournalApp/Interface/Feed/EmptyFeedRow.swift -> EmptyFeedRow.swift, parseTree: ParseTree(version: 727, statements: 3, providers: 1), update: nil, changesContextMemoizer: PreviewsPipeline.PreviewTranslationUnit.(unknown context at $34b4b9c4c).ChangesContextMemoizer(parseTree: ParseTree(version: 727, statements: 3, providers: 1), sourceIdentifier: file:///Users/bryananderson/Developer/JournalApp/JournalApp/Interface/Feed/EmptyFeedRow.swift -> EmptyFeedRow.swift, cachedValue: os.OSAllocatedUnfairLock<Swift.Optional<PreviewsModel.ParseTree.PreviewChangesContext>>(__lock: Swift.ManagedBuffer<Swift.Optional<PreviewsModel.ParseTree.PreviewChangesContext>, __C.os_unfair_lock_s>)), registryDeclarationMemoizer: PreviewsPipeline.PreviewTranslationUnit.(unknown context at $34b4b9bec).RegistryDeclarationMemoizer) | | builtTargetDescriptions: | == VERSION INFO: Tools: 16A5171c OS: 24A5264n PID: 906 Model: MacBook Pro Arch: arm64e == ENVIRONMENT: openFiles = [ /Users/bryananderson/Developer/JournalApp/JournalApp/Interface/Feed/EmptyFeedRow.swift ] wantsNewBuildSystem = true newBuildSystemAvailable = true activeScheme = JournalApp activeRunDestination = iPhone 15 Pro variant iphonesimulator arm64 workspaceArena = [x] buildArena = [x] buildableEntries = [ Remember.app ] runMode = JIT Executor == SELECTED RUN DESTINATION: name = iPhone 15 Pro eligible = true sdk = Optional(<DVTSDK:0x13870da30:'iphonesimulator18.0':Simulator - iOS 18.0:<DVTFilePath:0x600001e8c700:'/Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator18.0.sdk'>>) variant = Optional("iphonesimulator") device = Optional(<DVTiPhoneSimulator: 0x32f00d290> { SimDevice: iPhone 15 Pro (CF3C85BC-F559-4437-9072-7F30153B399B, iOS 18.0, Booted) PairedSim: <DVTiPhoneSimulator: 0x33733d150> { SimDevice: Apple Watch Series 9 (45mm) (627CE93E-EB02-4200-BE40-3DCB5C91DB44, watchOS 11.0, Shutdown) } }) == SELECTED RUN DESTINATION: Simulator - iOS 18.0 | iphonesimulator | arm64 | iPhone 15 Pro | Apple Watch Series 9 (45mm) jit enabled: true fallback to dynamic replacement: false

I don't know why after I connected to firebase in my app my preview just started to crash. here are some screen shots

I have just installed Xcode and the simulator is not working correctly I get the following error "Cannot preview in this file Unexpected error occurred"

The SwiftUI previews have been working fine in Xcode 16.0 beta, but ever since I added Firebase into my app, I've been getting error with previews. CrashReportError: IshaanCord crashed IshaanCord crashed. Check ~/Library/Logs/DiagnosticReports for crash logs from your application. Process: IshaanCord[5651] Date/Time: 2024-07-04 19:29:51 +0000 Log File: <none> "Cannot preview in this file" Does anyone know how to fix this? Thank you.

I have a multi-platform app with the SwiftUI code a separate Swift Package. Any Views with SwiftUI Previews break the compilation of the app. Here's the error message I get in Xcode: Showing All Messages ld: warning: Could not parse or use implicit file '/Applications/Xcode-beta.app/Contents/Developer/Platforms/WatchOS.platform/Developer/SDKs/WatchOS.sdk/System/Library/Frameworks/SwiftUICore.framework/SwiftUICore.tbd': cannot link directly with 'SwiftUICore' because product being built is not an allowed client of it Undefined symbols for architecture arm64_32: "(extension in SwiftUI):DeveloperToolsSupport.Preview.init(_: Swift.String?, traits: DeveloperToolsSupport.PreviewTrait&lt;DeveloperToolsSupport.Preview.ViewTraits&gt;..., body: @Swift.MainActor @Sendable () -&gt; SwiftUI.View) -&gt; DeveloperToolsSupport.Preview", referenced from: static BitnessViews.$s12BitnessViews33_ABDBADF565C741E50A2A5746CE94FCD9Ll7PreviewfMf_15PreviewRegistryfMu_.makePreview() throws -&gt; DeveloperToolsSupport.Preview in BitnessViews.o ld: symbol(s) not found for architecture arm64_32 clang: error: linker command failed with exit code 1 (use -v to see invocation) Could not parse or use implicit file '/Applications/Xcode-beta.app/Contents/Developer/Platforms/WatchOS.platform/Developer/SDKs/WatchOS.sdk/System/Library/Frameworks/SwiftUICore.framework/SwiftUICore.tbd': cannot link directly with 'SwiftUICore' because product being built is not an allowed client of it Undefined symbol: (extension in SwiftUI):DeveloperToolsSupport.Preview.init(_: Swift.String?, traits: DeveloperToolsSupport.PreviewTrait&lt;DeveloperToolsSupport.Preview.ViewTraits&gt;..., body: @Swift.MainActor @Sendable () -&gt; SwiftUI.View) -&gt; DeveloperToolsSupport.Preview Linker command failed with exit code 1 (use -v to see invocation) Any thoughts as to what might be going on here?

Hello, I‘ve started developing an App not to long ago on Xcode and I have noticed that I can’t see any progress or like preview of what I have coded so far and it’s starting to concern me. I have Xcode version 15.5 and I am coding with swift, everything works fine there is no error or anything preventing it to run but when I try to preview the only thing I see when I launch the Simulator and I open my app the only thing I see is a white page. Can someone please help me.

I wanted to get my SwiftData previews working in my primary project, so I started modeling them after the SampleTrips project. After messing around with that & being unable to make it work, I brought the same (working) sample code into my main project, unfortunately that's not working... I've attached the preview error (note, there's nothing in the Diagnostic Reports). //Sample code that works in it's own project, but not my primary target. import SwiftUI import SwiftData struct TestSwiftDataStuffView: View { let trip: Trip var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, \(trip.name)!") .padding() .foregroundColor(.red) } .padding() } } #Preview(traits: .sampleDataSecondary) { @Previewable @Query var trips: [Trip] TestSwiftDataStuffView(trip: trips.first!) } actor DataModelSecondary { struct TransactionAuthor { static let widget = "widget" } static let shared = DataModelSecondary() private init() {} nonisolated lazy var modelContainer: ModelContainer = { let modelContainer: ModelContainer let schema = Schema([ Trip.self ]) do { let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false, cloudKitDatabase: .none) modelContainer = try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError("Failed to create the model container: \(error)") } return modelContainer }() } @Model class Trip { @Attribute(.preserveValueOnDeletion) var name: String init(name: String) { self.name = name } } extension Trip { static var previewTrips: [Trip] { [ Trip(name: "Revenant"), Trip(name: "Newcastle"), Trip(name: "Bianca") ] } } struct SampleDataSecondary: PreviewModifier { static func makeSharedContext() throws -> ModelContainer { let config = ModelConfiguration(isStoredInMemoryOnly: true) let container = try ModelContainer( for: Trip.self, configurations: config ) SampleDataSecondary.createSampleData(into: container.mainContext) return container } func body(content: Content, context: ModelContainer) -> some View { content.modelContainer(context) } static func createSampleData(into modelContext: ModelContext) { Task { @MainActor in let sampleDataTrips: [Trip] = Trip.previewTrips let sampleData: [any PersistentModel] = sampleDataTrips //+ sampleDataLA + sampleDataBLT sampleData.forEach { modelContext.insert($0) } try? modelContext.save() } } } @available(iOS 18.0, *) extension PreviewTrait where T == Preview.ViewTraits { @MainActor static var sampleDataSecondary: Self = .modifier(SampleDataSecondary()) } Xcode16Preview.txt

Basically, in my widget/live activity, I want to extract reusable views into a separate file with an isolated view and preview. Dummy example below. I cannot do it because it says "missing previewcontext". The only way I've found is to add the view to my main app target, but I don't want to clutter my main app wiews that only exist in my widgets if I can avoid it. Can this be done somehow? Thoughts appreciated. Dummy example (tried with and without "previewLayout": struct StatusActivityView: View { let status: UserStatusData var body: some View { VStack(alignment: .center) { Text("Dummy example") }.background(.blue).padding(5) } } @available(iOS 16.2, *) struct StatusActivityView_Previews: PreviewProvider { static var previews: some View { let status = WidgetConstants.defaultEntry() return StatusActivityView(status: status).previewLayout(.sizeThatFits) } }

Hello, Today earlier I changed my macOS user account name and now I'm getting error at Xcode 16 at Preview. A piece of error report is: XOJITError: Could not create oop-jit code file directory /Users/victorvaz/Library/Developer/Xcode/UserData/Previews/Simulator Devices/CCCD8E24-3E82-4B02-9D30-0E2B5D09EB4A/data/Containers/Data/Application/D4EA132D-A318-4D58-8618-DFD428FD5F71/tmp/OOPJit/previews: Permission denied But "victorvaz" is my old macOS user account name, how can I make Xcode identify my new account name? Kind regards, Victor de Oliveira

I have been trying to get a preview to load for hours and it won't get passed the 'Preparing iPhone Simulator for Previews' and it has been days and nothing works. I've tried almost everything. I really need this to work, but it hasn't worked for weeks at this point.

Summary When trying to display SwiftUI previews, building the previews may fail with the following error: Linking failed: linker command failed with exit code 1 (use -v to see invocation) ld: warning: search path '/Applications/Xcode.app/Contents/SharedFrameworks-iphonesimulator' not found ld: warning: Could not find or use auto-linked framework 'CoreAudioTypes': framework 'CoreAudioTypes' not found Note that may app does not use CoreAudioTypes. Observation This issue seems to occur when two conditions are met: The SwiftUI view must be located in a Swift Package Somewhere in either the View or the #Preview a type from another package has to be used. Say I have to packages one named Model-package and one named UI-Package. The UI-Package depends on the Model-Package. If I have a SwiftUI view in the UI-Package that uses a type of the Model-Package either in the View itself or in the #Preview, then the described error occurs. If I have a View in the UI-package that does not use a type of the Model-Package anywhere in its View or #Preview then the SwiftUI Preview builds and renders successful. I created a bug report: FB13033812

I have two (local) Swift packages (both with a single library product): RemoteImage, which defines setImage(from:) function on UIImageView and SatelitUI package which directly depends on the first one and defines some views. But when I'm trying to preview views from the second package I'm getting the following error: linker command failed with exit code 1 (use -v to see invocation) LinkDylibError: Failed to build TrailerView.swift Linking failed: linker command failed with exit code 1 (use -v to see invocation) ld: warning: directory not found for option '-F/Applications/Xcode-beta.app/Contents/SharedFrameworks-iphonesimulator' Undefined symbols for architecture x86_64:   "(extension in RemoteImage):__C.UIImageView.setImage(from: Foundation.URL?) -> ()", referenced from:       (extension in SatelitUI_PreviewReplacement_TrailerView_2):SatelitUI.TrailerView.(previewupdate in _8C3731B0EF007627509BEEB93277D681)(with: SatelitUI.Trailer?) -> () in TrailerView.2.preview-thunk.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) Apparently, Xcode fails to link the library from the first package because it's dynamic. Static linking works as expected. It's a bug I believe?

I'm trying to preview a view from a swift package which is located in one of the target's directory subdirectories: . ├── Package.swift ├── README.md └── Sources &#9;&#9;└── SatelitUI &#9;&#9;&#9;&#9;└── Views &#9;&#9;&#9;&#9;&#9;&#9;└── MenuBar.swift When I'm previewing a view from the MenuBar.swift file I'm getting following error: NoBuildableEntriesError: active scheme does not build this file Select a scheme that builds a target which contains the current file, or add this file to a target that is built by the current scheme. Which is unexpected because the file should be a part of the SatelitUI target. The thing is it works just fine if I move it into the root target's directory (SatelitUI).

To reproduce: In Xcode, create a new project with SwiftData storage Add a new item in the preview — everything works fine so far Enable CloudKit sync for the target (add iCloud capability, check CloudKit, add a container) Go back to the preview and add a new item — Xcode will now freeze As soon as you modify the SwiftData storage, the preview freezes and the Xcode app becomes extremely slow until you either refresh the preview or restart Xcode.

Hi, i am currently updating my app in SwiftUI from iOS 16.4 to 18.0, i am getting in xcode these new warning @State' used inline will not work unless tagged with '@Previewable' so i fix the problem with the suggestions and add the new tag @Previewable and put the variable in the first line of the preview #Preview { @Previewable @State var enabled: Bool = true return NotificationLabel(enabled: $enabled, type: "test", icon: "star", title: "test", description: "test") } the problem is that my app is available from iOS 16.4 to iOS 18.0 and the preview gives me this error 'Previewable()' is only available in iOS 18.0 or newer but if i put a versione if at the top i get another error if #available(iOS 18.0, *){ @Previewable @State var enabled: Bool = true @Previewable' items must be at root scope in the preview block is there a way to silence the warning making a two version preview, one for iOS 18 and one for the previous versions?

// // ContentView.swift // HardApp // // Created by Besleaga Alexandru Marian on 14.06.2024. // import SwiftUI struct ContentView: View { var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundColor(.accentColor) Text("Hello, world!") } .padding() } } struct ContentView_Previews: PreviewProvider { static var previews: some View { ContentView() } } // A SwiftUI preview. #Preview { Use of unknown directive '#Preview' // The view to preview. } I'm trying to learn Xcode and got stuck on these error that I receive when trying to apply the macro #Preview, how can declare the directive so I can use it in my own code for the preview it offers ? Kind Regards

Hey Guys, a have some problens with Xcode preview for some reason I'm getting this error LinkDylibError: Failed to build CardDetailsScreen.swift Linking failed: linker command failed with exit code 1 (use -v to see invocation) ld: -make_mergeable can only be used when creating a dynamic library clang: error: linker command failed with exit code 1 (use -v to see invocation) previews_diagnostics_summary.txt

As someone who frequently uses Preview, it would be convenient to have the option to view the preview on another display. Are there any existing methods or plans to introduce a feature that allows us to pop out the previews to another screen?

Hey, I've opened an existing project with Xcode 16 Beta 1 (I'm also running macOS Sequoia). None of my previews work anymore. They simply crash with an error I don't quite understand: JITError ================================== | NoBuiltTargetDescriptionCouldBeFound | | translationUnit: PreviewTranslationUnit(moduleNamePrefix: "Previews_ErrorView", sourceIdentifier: file:///Users/dennis/Code/Project/Project/Components/ErrorView.swift -> ErrorView.swift, parseTree: ParseTree(version: 1848, statements: 5, providers: 0), update: nil, changesContextMemoizer: PreviewsPipeline.PreviewTranslationUnit.(unknown context at $3561fdc4c).ChangesContextMemoizer(parseTree: ParseTree(version: 1848, statements: 5, providers: 0), sourceIdentifier: file:///Users/dennis/Code/Project/Project/Components/ErrorView.swift -> ErrorView.swift, cachedValue: os.OSAllocatedUnfairLock<Swift.Optional<PreviewsModel.ParseTree.PreviewChangesContext>>(__lock: Swift.ManagedBuffer<Swift.Optional<PreviewsModel.ParseTree.PreviewChangesContext>, __C.os_unfair_lock_s>)), registryDeclarationMemoizer: PreviewsPipeline.PreviewTranslationUnit.(unknown context at $3561fdbec).RegistryDeclarationMemoizer) | | builtTargetDescriptions: The app builds and runs fun on a simulator and on device. Any ideas what this error means? Is this just an early Beta 1 bug or might there be anything I can do in my project to fix this? The WWDC24 demo projects all work fine and their previews are working as well. Thanks!