How to post and receive an NSNotifications (Objective C) | Notifications (in Swift)?

Send a notification:

[[NSNotificationCenter defaultCenter] postNotificationName:@"MyCacheUpdatedNotification" object:self];

Receive it:

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

Act on it:

- (void)cacheUpdated:(NSNotification *)notification {
[self load];
}

And dispose of it:

[[NSNotificationCenter defaultCenter] removeObserver:self];