Calling popViewControllerAnimated twice

Question

I've got a UINavigationController with a series of UIViewControllers on it. Under some circumstances, I want to pop back exactly two levels. I thought I could do it by calling popViewControllerAnimated twice in a row, but it turns out that the second time I call it, it's not popping anything and instead returning NULL. Do I need to store a reference to my destination VC and call popToViewControllerAnimated instead? I can do that, but it complicates my code since I'd have to pass the UIViewController* around as I'm pushing VCs onto the stack.

Here's the relevant snippet:

UIViewController* one = [self.navigationController popViewControllerAnimated:YES]; if (...) {     // pop twice if we were doing XYZ     UIViewController *two = [self.navigationController popViewControllerAnimated:YES];     // stored in "one" and "two" for debugging, "two" is always 0 here. } 

Am I doing something weird here? I want to write idiomatic code, so if the "right" way is to call popToViewControllerAnimated, or something else entirely, I'll happily change it.

Answer 1

In this case you would need to pop back to a specific viewcontroller in the navigationController like so:

[self.navigationController popToViewController:[[self.navigationController viewControllers] objectAtIndex:2] animated:YES]; 

That code would pop to the third viewcontroller on the navigationController's stack.

Answer 2

I think its better to count the number of view controllers in you stack and then subtract the number of view controllers you would like to pop.

 NSInteger noOfViewControllers = [self.navigationController.viewControllers count];  [self.navigationController   popToViewController:[self.navigationController.viewControllers   objectAtIndex:(noOfViewControllers-2)] animated:YES]; 

With this solution you wont mess up the pop if you add a new view to your project later.