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Call from invalid thread

See original GitHub issue

Describe the bug In my code I am doing this, in an async void called Connect, which is the function to be called for a button:

this.FindControl<ImageControl>("Screen").Source = new Bitmap("screen.png");

But it gives me an error:

System.InvalidOperationException
  HResult=0x80131509
  Message=Call from invalid thread
  Source=Avalonia.Base
  StackTrace:
   at Avalonia.Threading.Dispatcher.VerifyAccess() in /_/src/Avalonia.Base/Threading/Dispatcher.cs:line 48
   at Avalonia.AvaloniaObject.GetValue[T](StyledPropertyBase`1 property) in /_/src/Avalonia.Base/AvaloniaObject.cs:line 252
   at Avalonia.Controls.NameScope.GetNameScope(StyledElement styled) in /_/src/Avalonia.Styling/Controls/NameScope.cs:line 37
   at Avalonia.Controls.NameScopeExtensions.<>c.<FindNameScope>b__4_0(StyledElement x) in /_/src/Avalonia.Styling/Controls/NameScopeExtensions.cs:line 114
   at System.Linq.Enumerable.SelectEnumerableIterator`2.MoveNext()
   at System.Linq.Enumerable.TryGetFirst[TSource](IEnumerable`1 source, Func`2 predicate, Boolean& found)
   at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
   at Avalonia.Controls.NameScopeExtensions.FindNameScope(ILogical control) in /_/src/Avalonia.Styling/Controls/NameScopeExtensions.cs:line 116
   at Avalonia.Controls.ControlExtensions.FindControl[T](IControl control, String name) in /_/src/Avalonia.Controls/ControlExtensions.cs:line 59
   at ScreenShareClient.MainWindow.<Connect>b__2_1(SocketIOResponse data) in C:\Users\HP\Desktop\Socket.IO Screen Share\Client\MainWindow.axaml.cs:line 46
   at SocketIOClient.Packgers.MessageEventPackger.Unpack(SocketIO client, String text)
   at SocketIOClient.Packgers.MessagePackger.Unpack(SocketIO client, String text)
   at SocketIOClient.Packgers.PackgeManager.Unpack(String msg)
   at SocketIOClient.WebSocketClient.ClientWebSocket.<ListenAsync>d__16.MoveNext()

Expected behavior For the image source to change

Desktop (please complete the following information):

OS: Windows 10
Version: 0.10.4

Issue Analytics

State:
Created 2 years ago
Comments:6 (2 by maintainers)

Top GitHub Comments

1reaction

monke8555commented, Jun 2, 2021

@Gillibald ohhh ok so normal code but at that line:

Dispatcher.UIThread.InvokeAsync(async () => {
     this.FindControl < ImageControl > ("Screen").Source = new Bitmap("screen.png");
})

0reactions

monke8555commented, Jun 2, 2021

Thank you it works

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