DockableContent problem with closing [Urgent]

Nov 2, 2009 at 12:18 PM
Edited Nov 3, 2009 at 7:07 AM


I have downloaded latest version from this site:

Now go to the AvalonDockTest3 (Window3.xaml). In my procject I have removed <ad:DocumentPane Visibility="Visible"/> line. So there is only two DockableContents.
Until these two contents are in one column everything is ok - I can close both. But when I place them in one row (side by side) after closing both of them something strange happens - smoething similar to DockableContent appears(with bar and three buttons on it), but when I am trying to close it I am getting an error:
"Object reference not set to an instance of an object."

How this problem can be solved?
Or what I have to do to manage library/application to display at least two dockable contents - when there are two contents, user cannot close them. When for example we have 3 contents, user can close only one, When we have 4 contents, 2 are closeable, 5 - 3, 6 - 4, etc.