Send and receive messages through NSNotificationCenter in Objective-C?

Question

I am attempting to send and receive messages through NSNotificationCenter in Objective-C. However, I haven\'t been able to find any examples on how to do this.

Answer 1

There is also the possibility of using blocks:

NSOperationQueue *mainQueue = [NSOperationQueue mainQueue];
[[NSNotificationCenter defaultCenter] 
     addObserverForName:@"notificationName" 
     object:nil
     queue:mainQueue
     usingBlock:^(NSNotification *notification)
     {
          NSLog(@"Notification received!");
          NSDictionary *userInfo = notification.userInfo;

          // ...
     }];

Apple's documentation