WPF : Dispatcher processing has been suspended, but messages are still being processed

Question

I Have a WPF Project, When i try to Run This Code On RowLoad Event I got below Error :

private void ParentGridView_OnRowLoaded(object sender, EventArgs e)
{
         


        

Answer 1

This answer describes the same situation as yours. (It references this answer on a different website).

The dispatcher processing is suspended to avoid reentrancy problems when updating the visual tree.

If you really need to display a message box in response to your "Row Loaded" event, you need to defer the call using `Dispatcher.BeginInvoke().

So, replace:

MessageBox.Show(((RadGridView)sender).Columns.Count.ToString(CultureInfo.InvariantCulture));

with:

var msg = ((RadGridView)sender).Columns.Count.ToString(CultureInfo.InvariantCulture);
Dispatcher.BeginInvoke(new Action(() => MessageBox.Show(msg)));

If this code is in a WPF object, then the Dispatcher property is available. Otherwise, you need to get it from somewhere else.