LostFocus crash

[maximilien-noal]

** Issue **

when clicking on edit... to edit an existing breakpoint:

Unhandled exception. System.Reflection.AmbiguousMatchException: Ambiguous match found for 'Avalonia.Input.FocusManager Avalonia.Input.IInputElement GetFocusedElement()'.
at System.RuntimeType.GetMethodImpl(String name, BindingFlags bindingAttr, Binder binder, CallingConventions callConv, Type[] types, ParameterModifier[] modifiers)
at System.Type.GetMethod(String name, BindingFlags bindingAttr)
at Avalonia.Controls.Utils.AvaloniaInternalCompatibilityHelper.GetFocusedElement(InputElement inputElement)
at Avalonia.Controls.DataGrid.DataGrid_LostFocus(Object sender, RoutedEventArgs e)
at Avalonia.Interactivity.EventRoute.RaiseEventImpl(RoutedEventArgs e)
at Avalonia.Interactivity.EventRoute.RaiseEvent(Interactive source, RoutedEventArgs e)
at Avalonia.Interactivity.Interactive.RaiseEvent(RoutedEventArgs e)
at Avalonia.Input.KeyboardDevice.SetFocusedElement(IInputElement element, NavigationMethod method, KeyModifiers keyModifiers, Boolean isFocusChangeCancellable)
at Avalonia.Input.FocusManager.Focus(IInputElement element, NavigationMethod method, KeyModifiers keyModifiers)
at Avalonia.Input.InputElement.Focus(NavigationMethod method, KeyModifiers keyModifiers)
at Avalonia.Input.FocusManager.OnPreviewPointerEventHandler(Object sender, RoutedEventArgs e)
at Avalonia.Reactive.LightweightObservableBase1.PublishNext(T value) at Avalonia.Interactivity.EventRoute.RaiseEventImpl(RoutedEventArgs e) at Avalonia.Interactivity.EventRoute.RaiseEvent(Interactive source, RoutedEventArgs e) at Avalonia.Interactivity.Interactive.RaiseEvent(RoutedEventArgs e) at Avalonia.Input.MouseDevice.MouseDown(IMouseDevice device, UInt64 timestamp, IInputRoot root, Point p, PointerPointProperties properties, KeyModifiers inputModifiers, IInputElement hitTest) at Avalonia.Input.MouseDevice.ProcessRawEvent(RawPointerEventArgs e) at Avalonia.Threading.Dispatcher.Send(SendOrPostCallback action, Object arg, Nullable1 priority)
at Avalonia.Controls.PresentationSource.HandleInput(RawInputEventArgs e)
at Avalonia.Win32.WindowImpl.AppWndProc(IntPtr hWnd, UInt32 msg, IntPtr wParam, IntPtr lParam)
at Avalonia.Win32.WindowImpl.WndProcMessageHandler(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.StartCore(String[] args)
at Avalonia.Controls.ApplicationLifetimes.ClassicDesktopStyleApplicationLifetime.Start(String[] args)
at Avalonia.ClassicDesktopStyleApplicationLifetimeExtensions.StartWithClassicDesktopLifetime(AppBuilder builder, String[] args, ShutdownMode shutdownMode)
at Spice86.Program.Main(String[] args) in C:\Users\noalm\source\repos\Spice86\src\Spice86\Program.cs:line 53

C:\Users\noalm\source\repos\Spice86\src\Spice86\bin\Release\net10.0\Spice86.exe (process 49280) exited with code -532462766 (0xe0434352).
Press any key to close this

** What to avoid **

A workaround in the client application:

Fixed in OpenRakis/Spice86@0af9b33.

The crash is in Spice86.DataGrid 0.1.0: its DataGrid_LostFocus class handler calls AvaloniaInternalCompatibilityHelper.GetFocusedElement, which uses Type.GetMethod("GetFocusedElement", ...) and now matches multiple Avalonia 12 overloads -> AmbiguousMatchException. Clicking Edit... moved focus off the data grid and tripped that path.

Workaround: the toolbar buttons (New..., Edit..., Remove, Remove All, Disable all, Enable all, Toggle) are now Focusable="False", so clicking them no longer steals focus from the grid and the buggy LostFocus handler never runs. Click handling is unaffected. Proper fix belongs upstream in the Spice86.DataGrid package.

dotnet build: 0 warnings/0 errors. dotnet test (UI): 51 passed.

see: OpenRakis/Spice86#2164

** Approach **

• Use AvaloniaFact and UI TDD (red test, passing test)

** Afterwards **

New nuget release