Difference between presentModalViewController and presentViewController?

Question

In iOS 5 SDK, there're two methods of UIViewController, presentModalViewController:animated: and presentViewController:animated:completion:.

What's the difference between these two method?

The documentation says: The presentViewController:animated:completion: method is the preferred way to present a modal view as of iOS 5.0.

If I use a presentModalViewController:animated in iOS 5, will it causes a bug?

Are they functionally-same?

Answer 1

They seem to do the same thing as apple documentation points out, as of iOS 5.0 presentViewController is the preferred way to present view controllers, it seems that presentViewController now lets you have a completion handler, whereas before you did not have that.

And no the older presentModalViewController should be fine on iOS 5.0, if it caused a bug that would be a problem for all the older apps and would not be very backward compatible. Furthermore it seems that now with presentViewController you can get a lot more info about the viewController hierarchy as we have presentingViewController, presentedViewController properties.

Answer 2

Another important note is that presentModalViewController will be deprecated in the future, as mentioned in the UIViewController.h of the UIKit framework (Xcode version 4.3.1):

// Display another view controller as a modal child. Uses a vertical sheet transition if animated.This method has been replaced by presentViewController:animated:completion:
// It will be DEPRECATED, plan accordingly.
- (void)presentModalViewController:(UIViewController *)modalViewController animated:(BOOL)animated; 

// Dismiss the current modal child. Uses a vertical sheet transition if animated. This method has been replaced by dismissViewControllerAnimated:completion:
// It will be DEPRECATED, plan accordingly.
- (void)dismissModalViewControllerAnimated:(BOOL)animated;