Access Container View Controller from Parent iOS

Question

in iOS6 I noticed the new Container View but am not quite sure how to access it\'s controller from the containing view.

Scenario:

Answer 1

you can write like this

- (IBAction)showDetail:(UIButton *)sender {  
            DetailViewController *detailVc = [self.childViewControllers firstObject];  
        detailVc.lable.text = sender.titleLabel.text;  
    }  
}