I'm looking for some good information on subclassing. I've really been looking into subclassing for interface design purposes, and for example went through a tutorial on subclassing UIAlertView to achieve a different look, but I would like to find more information on subclassing as a general techinque. I think being able to subclass any UI-based element of an objective c application (such as UIButton, UIToolbar, UITabBar Etc) would really improve me as a developer. So, any links or publications you guys think I should check out would be great! :D
Subclassing is a great thing to get comfortable with because once you get proficient at it implementing custom controls becomes very easy.
Each class has different caveats for subclassing, so you really need to read the docs for each class. It also helps to read through the header files for the class (not on my mac right now but I think you can right click a class name and it will have an option to show you the header) as they usually have good information in there about subclassing.
I would also recommend looking at the Cocoa Controls Website. I think all of the controls on there have the source code available so you can see the techniques that people are using.