So I'm watching the video at http://channel9.msdn.com/Events/MIX/MIX10/EX14. During the demo at 33 minutes in, something magical happens, and the system knows to disable the command button. Can anyone explain how it knows? I can't use this stuff if I can't figure out how it works.
@MasterRanger: It's the WPF Command framework. ICommand.CanExecute. Details beyond that? I'd imagine there's an event raised to any listeners (which would be anything bound to the command instance). The beauty of a framework is that I don't need to know how it works, just how to use it.
From some quick searching, it seems that the CommandManager class is involved.
@MasterRanger: Yea. The whole CanExecute thing. Take a look at this video.
It helped me understand, hopefully it will help you.
Reference: Here is the page where the link to Jason's wmv lives. http://blog.lab49.com/archives/2650