I tried to reproduce your issue on our side with our latest official release and it seems like the code works as expected. The behavior of the control can be seen in the following picture.
As you can see the third item disappears when I set its Visibility to Collapsed.
Can you please clarify which version of our dlls you use. Also, it will be great if you can reproduce the reported behavior in a separate project and send it over. By doing so I will be able to further investigate the reasons behind the reported behavior.
Thank you for your kind cooperation.
Pavel R. Pavlov
TRY TELERIK'S NEWEST PRODUCT - EQATEC APPLICATION ANALYTICS for SILVERLIGHT.
Learn what features your users use (or don't use) in your application. Know your audience. Target it better. Develop wisely.
Sign up for Free application insights >>