I am trying to implement some radio button functionality. I found this page but when I try to use the classes NSButtonCell, NSRect and NSMatrix I get the error:
Use of undeclared identifier 'NSButtonCell'
Use of undeclared identifier 'NSRect'
Use of undeclared identifier 'NSMatrix'
I tried to import AppKit/AppKit.h but I get file not found. After reading this I changed it to UIKit/UIKit.h but the problem remains.
How can I solve this?