Question

I have added one view controller to my first view controller as aa subview by using self.view add subview:secondview now when I’ll rotate the device

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration;

method calls for only parent view Now I also want to call that method for child view controller so i can make required changes in child view controller also.
So for that what I have to do??

-Thanks in advance.

Answer 1

In WWDC 2011 Session 102 on view controller containment, they mention that a failure to keep one’s view controller hierarchy synchronized with the view hierarchy can result in rotation events problems. They explicitly point out that if you just grab a view controller’s view and add it as a subview of the main view, without adding the controller, itself, to the view controller hierarchy, you won’t get these rotation events. In that WWDC session, they also suggest that if you want to “future-proof” your app, you’ll want to manage view controllers properly.

From a pragmatic perspective, this means that as you go from one view to another, that you really should be transitioning the view controllers. Most commonly this means using pushViewController or presentViewControllerAnimated (formerly presentModalViewController). Or you can use view controller containment (see that WWDC session or look at the very brief comments about containment in the UIViewController Class Reference). But don’t just grab the view from another view controller and just add it as a subview of the current view.

If you pursue view controller containment, at a minimum, you could add your child view’s controller to the hierarchy via:

[self addChildViewController:childController];
[childController didMoveToParentViewController:self];