Can't run the application

[ArkanYahya]

When I try to run the app this error happened:

System.InvalidOperationException
HResult=0x80131509
Message=Deserialization of init-only properties is currently not supported in source generation mode.
Source=FAControlsGallery
StackTrace:
at FAControlsGallery.ViewModels.FAControlsJsonSerializerContext.<>c.b__34_3(Object obj, String value) in \FluentAvalonia-master\samples\FAControlsGallery\System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\FAControlsJsonSerializerContext.PageBaseViewModel.g.cs:line 85
at System.Text.Json.Serialization.Metadata.JsonPropertyInfo1.ReadJsonAndSetMember(Object obj, ReadStack& state, Utf8JsonReader& reader) at System.Text.Json.Serialization.Converters.ObjectDefaultConverter1.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
at System.Text.Json.Serialization.JsonConverter1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value) at System.Text.Json.Serialization.JsonCollectionConverter2.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, TCollection& value)
at System.Text.Json.Serialization.JsonConverter1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value) at System.Text.Json.Serialization.JsonConverter1.ReadCore(Utf8JsonReader& reader, JsonSerializerOptions options, ReadStack& state)
at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan1 utf8Json, JsonTypeInfo jsonTypeInfo, Nullable1 actualByteCount)
at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan1 json, JsonTypeInfo jsonTypeInfo) at System.Text.Json.JsonSerializer.Deserialize[TValue](String json, JsonTypeInfo1 jsonTypeInfo)
at FAControlsGallery.ViewModels.CoreControlsPageViewModel..ctor(String coreControlsJson) in \FluentAvalonia-master\samples\FAControlsGallery\ViewModels\CoreControlsPageViewModel.cs:line 12
at FAControlsGallery.Views.MainView.InitializeNavigationPages() in \FluentAvalonia-master\samples\FAControlsGallery\Views\MainView.axaml.cs:line 113
at FAControlsGallery.Views.MainView.b__1_0() in \FluentAvalonia-master\samples\FAControlsGallery\Views\MainView.axaml.cs:line 76
at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state) in //src/libraries/System.Private.CoreLib/src/System/Threading/ExecutionContext.cs:line 268
--- End of stack trace from previous location ---
at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state) in //src/libraries/System.Private.CoreLib/src/System/Threading/ExecutionContext.cs:line 293
at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread) in //src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs:line 2349
--- End of stack trace from previous location ---
at FluentAvalonia.UI.Windowing.SplashScreenContext.d__11.MoveNext() in \FluentAvalonia-master\src\FluentAvalonia\UI\Windowing\AppWindow\SplashScreenContext.cs:line 31
at FluentAvalonia.UI.Windowing.AppWindow.d__5.MoveNext() in \FluentAvalonia-master\src\FluentAvalonia\UI\Windowing\AppWindow\AppWindow.cs:line 167
at System.Threading.Tasks.Task.<>c.b__128_0(Object state) in //src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs:line 1914
at Avalonia.Threading.SendOrPostCallbackDispatcherOperation.InvokeCore()
at Avalonia.Threading.DispatcherOperation.Execute()
at Avalonia.Threading.Dispatcher.ExecuteJob(DispatcherOperation job)
at Avalonia.Threading.Dispatcher.ExecuteJobsCore(Boolean fromExplicitBackgroundProcessingCallback)
at Avalonia.Threading.Dispatcher.Signaled()
at Avalonia.Win32.Win32DispatcherImpl.DispatchWorkItem()
at Avalonia.Win32.Win32Platform.WndProc(IntPtr hWnd, UInt32 msg, IntPtr wParam, IntPtr lParam)
at Avalonia.Win32.Interop.UnmanagedMethods.DispatchMessage(MSG& lpmsg)
at Avalonia.Win32.Win32DispatcherImpl.RunLoop(CancellationToken cancellationToken)
at Avalonia.Threading.DispatcherFrame.Run(IControlledDispatcherImpl impl)
at Avalonia.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
at Avalonia.Threading.Dispatcher.MainLoop(CancellationToken cancellationToken)
at Avalonia.Controls.ApplicationLifetimes.ClassicDesktopStyleApplicationLifetime.Start(String[] args)
at Avalonia.ClassicDesktopStyleApplicationLifetimeExtensions.StartWithClassicDesktopLifetime(AppBuilder builder, String[] args, Action`1 lifetimeBuilder)
at FAControlsGallery.Desktop.Program.Main(String[] args) in \FluentAvalonia-master\samples\FAControlsGallery.Desktop\Program.cs:line 12

[ScoPeZs]

I'm having the same error. Have you found a fix for it?

[denisioan]

Me too. Exactly the same issue. Any ideas how to fix it?

[yumikou]

I changed the sample's TargetFramework to net9.0 and it worked. Of course you need to install the visual studio preview version and net9 preview sdk first.

[robloo]

@hez2010 Can you provide any insight here? It's likely related to the PR: #493 which can't handle init-only properties until .net 9+.

I'm not sure why this is coming up now for only some people though.

[hez2010]

Changing the init property to set should resolve this issue.
I think we can add a package reference to the version of System.Text.Json which supports init properties manually for .net standard 2.0.
@amwx what do you think?

[amwx]

This will be fixed in 2.1 - already in that branch. *inserts grumpy remark about not being able to do simple things because .net team releases incomplete features*