NSToolbarItemValidation Mac OS X 10.0

This informal protocol declares the method validateToolbarItem:, which allows targets of toolbar item actions to decide whether or not the toolbar item should be enabled. This method is similar in purpose and operation to the method validaeMenuItem:, which is found in the the NSMenuValidation protocol.

@interface NSObject (NSToolbarItemValidation)
 // Instance Methods
   - (BOOL)validateToolbarItem:(NSToolbarItem *)theItem;

    Part II: API Quick Reference
    Chapter 13. Foundation Classes