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Revision: 43674
at March 29, 2011 13:33 by magickaito
Initial Code 
@implementation TestClass

- (void) dealloc
{
    // If you don't remove yourself as an observer, the Notification Center
    // will continue to try and send notification objects to the deallocated
    // object.
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    [super dealloc];
}

- (id) init
{
    self = [super init];
    if (!self) return nil;

    // Add this instance of TestClass as an observer of the TestNotification.
    // We tell the notification center to inform us of "TestNotification"
    // notifications using the receiveTestNotification: selector. By
    // specifying object:nil, we tell the notification center that we are not
    // interested in who posted the notification. If you provided an actual
    // object rather than nil, the notification center will only notify you
    // when the notification was posted by that particular object.

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(receiveTestNotification:) 
                                                 name:@"TestNotification"
                                               object:nil];

    return self;
}

- (void) receiveTestNotification:(NSNotification *) notification
{
    // [notification name] should always be @"TestNotification"
    // unless you use this method for observation of other notifications
    // as well.

    if ([[notification name] isEqualToString:@"TestNotification"])
        NSLog (@"Successfully received the test notification!");
}

@end

... somewhere else in another class ...

- (void) someMethod
{
    // All instances of TestClass will be notified
    [[NSNotificationCenter defaultCenter] postNotificationName:@"TestNotification" object:self];
}
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                                        Initial Description
                                        

                                    

                                    
thanks to http://stackoverflow.com/questions/2191594/how-to-send-and-receive-message-through-nsnotificationcenter-in-objective-c

                                

                                                            

                                    

                                        

                                        Initial Title
                                        

                                    

                                    
Dispatch and Receive events in ObjectiveC

                                

                                                            

                                    

                                        

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                                        Initial Language
                                        

                                    

                                    
Objective C