Trigger events when switching views
secondView *secondViewController;
secondViewController = [[SecondView alloc]
                      initWithNibName:@"SecondView" bundle:nil];
[self.view addSubview:SecondViewController.view];

[self.view removeFromSuperView];

[self.navigationController pushViewController:secondViewController animated:YES];

- (void) backButtonClicked:(id)sender {
    [self.view removeFromSuperView];
    [[NSNotificationCenter defaultCenter] postNotificationName:@"back"
                                                        object:self.view];
}

- (void) pushSecondViewController {
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(secondViewDidGoBack:)
                                                 name:@"back"
                                               object:secondViewController.view];

    SecondView *secondViewController = [[SecondView alloc] initWithNibName:@"SecondView"
                                                                    bundle:nil];
    [self.view addSubview:secondViewController.view];
}

- (void) secondViewDidGoBack:(NSNotification *)notification {
    [[NSNotificationCenter defaultCenter] removeObserver:self];

    NSLog(@"My Second View Did Go back !");
}