multi thread error

[heartacker]

when we use

Task.Run(()=>
{
	A = 10;
});

throw a runtime error

Text="{x:Bind A}"

[levitali]

I suppose, setting A property raises PropertyChanged event. So that the value of the property is immediately set to the TextBlock’s Text property.

You can set control's property only in main thread. Updating UI from background thread is not supported in any (known me) UI frameworks.

[heartacker]

Thanks. And could you please help me or provide a Solution to deal with this problem?

I need to update the binding property in the task /new thread

[levitali]

You can set properties in a background thread, but you have to delegate raising PropertyChanged event to the main thread.

As an example you could look here:

https://github.com/levitali/CompiledBindings/blob/master/source/XF/XFTest/ViewModels/SynchronizedObservableObject.cs

Though the project is for Xamarin Forms, there are compiler switches for many other UI frameworks.