UIView vertical flip animation

Question

I have an iOS UIView with UIViewAnimationTransitionFlipFromRight. I need it to flip vertically though. The page curl transition won\'t cut it. I assume this wil

Answer 1

As of iOS 5.0, there's no need to write your own Core Animation transformation to do vertical flips. Just use UIKit's UIViewAnimationOptionTransitionFlipFromTop and UIViewAnimationOptionTransitionFlipFromBottom transitions, and all this stuff becomes a single method call.

These behave analagously to UIViewAnimationOptionTransitionFlipFromLeft and UIViewAnimationOptionTransitionFlipFromRight (which have been around since iOS 2.0).

Example usage:

[UIView transitionFromView:viewToReplace
                    toView:replacementView
                  duration:1
                   options:UIViewAnimationOptionTransitionFlipFromBottom
                completion:nil];

The above code will vertically flip the superview of viewToReplace. At the halfway point in the animation, at the instant when the superview is perpendicular to the screen and thus invisible, viewToReplace gets replaced by replacementView.

It's that easy.