Question

I am developing an app based on the Master-View template provided by Apple (it consists of two ViewControllers, the MasterViewController and the DetailViewController). I have added a Model for communication with my server.

However, when my Model receives a message from the server, it needs to call a method in the MasterViewController or DetailViewController class. How can I do this?

All help is greatly appreciated.

Answer 1

You could fire notifications from the model, which are handled by the Master and Detail View controllers.

In the model:

- (void)receivedMessageFromServer {
    // Fire the notification
    [[NSNotificationCenter defaultCenter] postNotificationName:@"ReceivedData" 
                                                        object:nil];   
}

Handle the “ReceivedData” notification in your View Controller(s):

- (void)viewDidLoad {
    [NSNotificationCenter defaultCenter] addObserver:self 
                                            selector:@selector(receivedDataNotification:) 
                                                name:@"ReceivedData" 
                                              object:nil];
}

- (void)receivedDataNotification:(id)object {
    NSLog(@"Received Data!");
}