By design when the BusyIndicator control is displayed (its IsBusy property is set to True) the IsEnabled property of all controls placed inside it is set to False.
I recorded a short video for you that shows how the IsEnabled property is updated correctly. Please let us know if we have missed something.
TRY TELERIK'S NEWEST PRODUCT - EQATEC APPLICATION ANALYTICS for WPF.
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 >>