I’ve come across a bug in the .Net Framework when developing a Windows Forms app, which has a Splash Screen.
On some users machines, the application threw a “Invoke or BeginInvoke cannot be called on a control until the window handle has been created.” exception at startup.
This is seemingly to do with code executing before the splash screen has fully loaded. It appears that the exception happens just after startup and on slow or busy machines.
Microsoft have a workaround for this issue, which I found on the MSDN forums;
http://social.msdn.microsoft.com/Forums/en/winforms/thread/bdc00055-338d-4a4a-a881-14b242b83b83
Create a Boolean user setting “LoadFinished” and set it to be false.
In the Splash Screen load event add this to the start;
My.Settings.LoadFinished = False
and at the end of the event;
My.Settings.LoadFinished = True
In ApplicationEvents file add this;
Private Sub MyApplication_Startup(sender As Object, e _
As Microsoft.VisualBasic.ApplicationServices.StartupEventArgs)_
Handles Me.Startup
Try
If Not Me.SplashScreen Is Nothing Then
While My.Settings.LoadFinished = False
System.Threading.Thread.Sleep(50)
End While
End If
My.Settings.LoadFinished = False
Catch ex As Exception
EmailError(ex)
End Try
End Sub
In my solution, I also needed to enclose the above with the correct namespace and partial class construct;
Namespace My
Partial Friend Class MyApplication
Private Sub MyApplication_Startup(sender As Object, e As Microsoft.VisualBasic.ApplicationServices.StartupEventArgs) Handles Me.Startup
Try
If Not Me.SplashScreen Is Nothing Then
While My.Settings.LoadFinished = False
System.Threading.Thread.Sleep(50)
End While
End If
My.Settings.LoadFinished = False
Catch ex As Exception
End Try
End Sub
End Class
End Namespace
Hope this helps somebody!
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