listening for changes to active application

Hi, How can I be notified when the foreground application changes? I found "activeApplication" in NSWorkspace. Is there a way to observe changes to that property? I tried the following, which doesn't seem to work... [[NSWorkspace sharedWorkspace] addObserver:obs forKeyPath:@"activeAp

cross development, missing methods

Hi, In short, my question is: when cross developing for multiple OS versions, how do people deal with Objective-C methods that exist in only some of the versions? Do you have multiple targets compiling against different SDKs? Details... I'm on 10.5 with Xcode 3.1 and I tried to create a