How to get notified of popped view in UINavigationController?

Question

I want to perform a action when the user pressed the back button on my UINavigationController when arrived at a certain UIViewController.

Unfortunately it looks like UINavigationControllerDelegate doesn't have any methods to get notified of the popping of views.

As a workaround I now have in the viewDidDisappear method my action, that only gets fired when animated is YES. This works, but it's a bit ugly.

How should I do this properly?

Answer 1

The most popular way of handling a pop from navigation view controller (as well as from modal) is implementing viewWillDisappear for your view controller.

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];

    if (self.isMovingFromParentViewController || self.isBeingDismissed) {
        // This view controller is being popped or dismissed
    }
}

Answer 2

If you have a reference to the controller down the stack, the one which will show when this one is popped, you can register as a delegate and check it through

navigationController:willShowViewController:animated: