What is parameter `object` in NSNotification addObserver:?

Question

One of my class named Message.m is posting a notification with an object sentObject as below

NSDictionary *sentObject = [NSDictionary dictionary         


        

Answer 1

You can use it to pass any object with the notification. The receiver of the notification will then be able to access that object. For example, you could implement dataReloaded like this:

- (void)dataReloaded:(NSNotification *)notification {

    NSLog(@"%@", notification.object); // this will log the object you passed in addObserver:selector:name:object:

}

It can be useful when you want to pass on data with your notification, so that the receiver of a notification can use that data too.