title: How do I view my class model using xcode4 or another tool?
body: <p>Is there a way to view the entire class model for my project graphically? I have several classes and I'd like to see things like someClass 'is a' window and 'has a' frame. I know I could use something like OMNIGRAFFLE and make one myself but is there something built into xcode4 or some other tool that does this?</p>