Writing classes that work in both iOS and Mac OS

Question

What is a good way to write classes that can be used in both iOS and Mac OS applications? I'm not trying to get a full cross-platform UI solution here, just a way to use several model classes from my iPhone app in a support application running on the Mac. Some of those classes require a few minor changes to get them compiling under Mac OS. This seems like a call for macros, but I don't know which ones are typically used. Any suggestions or shared experience would be appreciated.

Answer 1

One way is like this example from a iOS/OSX multi-platform class header file:

#if TARGET_OS_IPHONE        
#import <UIKit/UIKit.h>
#else
#import <Cocoa/Cocoa.h>
#endif TARGET_OS_IPHONE