How to change the Push and Pop animations in a navigation based app

Question

I have a navigation based application and I want to change the animation of the push and pop animations. How would I do that?

Edit 2018

Ther

Answer 1

Just use:

ViewController *viewController = [[ViewController alloc] init];

UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:viewController];
navController.navigationBarHidden = YES;

[self presentViewController:navController animated:YES completion: nil];
[viewController release];
[navController release];