Steps to reproduce:
- Create a form with RadDock on it
- Use the following code in another form:
Using frm As New FormWithDock()
frm.ShowDialog()
End Using
- Close the dialog (FormWithDock) -> exception is thrown
WORKAROUND - dispose the dock on form closing:
Protected Overrides Sub OnClosing(e As System.ComponentModel.CancelEventArgs)
RadDock1.Dispose()
MyBase.OnClosing(e)
End Sub
I also found this and can sometimes manifest itself as the following exception at System.Drawing.Region.GetHrgn(Graphics g) at System.Windows.Forms.Control.GetHRgn(Region region) at System.Windows.Forms.Control.OnHandleCreated(EventArgs e)