Learning Objective-C

I try creating 3DCG viewer on Mac OS X, therefore I learn Objective-c and Cocoa.

Cocoa is very unique framework.
I know Win32 API, Java, Gtk, X Window.
Using these gui frameworks need long long procedure.

But, Procedure of Cocoa is not.

In Addition, Interface builder that is developing tool of Cocoa is very useful.

I like Cocoa.