
Keeping It Running 9 89
In common use, a category (such as NSToolbarDelegate) ex-
tends another class~such as NSObject in this case:
@interface NSObject (NSToolbarDelegate)
- (NSToolbarItem *)toolbar: (NSToolbar *)toolbar
itemForItemIdentifier-(NSString *) itemIdentifier
willBeInsertedIntoToolbar. (BOOL) flag;
- (NSArray *)toolbarDefaultItemIdentifiers-
(NSToolbar*) toolbar ;
- (NSArray *)toolbarAllowedItemIdentifiers-
(NSToolbar*) toolbar ;
@end
Another category also extends
NSObject~NSToolbarNotifi-
cations:
@interface NSObject (NSToolbarNotifications)
- (void) toolbarWillAddItem. (NSNotification *)no-
tification;
- ...