Horizontal flip direction in iOS Storyboards

Question

I have set up two view controllers in my Storyboard, each with an action button. I set up two segues:

1. From the first view controller to the second view controller: Modal, Flip Horizontal.
2. From the second view controller to the first view controller: Modal, Flip Horizontal.

Everything works, but I would like it to flip one way and back, now it flips the same direction for both view controllers.

What is the easiest way to make a flip-flip back effect?

Answer 1

I encountered the same problem, and hopefully found a solution.

I used a custom segue to flip the way back. Here is the code of my FlipLeftSegue

@implementation FlipLeftSegue
- (void)perform
{
    UIViewController *src = (UIViewController *) self.sourceViewController;
    UIViewController *dst = (UIViewController *) self.destinationViewController;    

    [UIView beginAnimations:@"LeftFlip" context:nil];
    [UIView setAnimationDuration:0.8];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:src.view.superview cache:YES];
    [UIView commitAnimations];

    [src presentViewController:dst animated:NO completion:nil];
}
@end

The only problem I found to this solution, is that the viewDidAppear method is called immediatly when the animation starts. Whereas with normal segue, it is called after the animation.

Answer 2

Instead of creating a new presentation of a ViewController, I'd suggest accessing the property for presentingViewController on the second ViewController, and then calling -dismissViewControllerAnimated:completion: on it. Like so:

-(IBAction)someResponderToYourCancelButtonOrWhatever:(id)sender {
    // Do some stuff
    [self.presentingViewController dismissViewControllerAnimated:YES completion:nil];
}

Answer 3

You better use this code in NSZombie's answer:

- (void)swapChildVCFrom:(UIViewController *)from to:(UIViewController *)to options:(enum UIViewAnimationOptions)options
{
    [self addChildViewController:to];
    [from willMoveToParentViewController:nil];

    // Adjust the new child view controller's view's frame
    // For example here just set it to fill the parent view
    to.view.frame = self.view.bounds;

    [self transitionFromViewController:from
                      toViewController:to
                              duration:1.0
                               options:options
                            animations:nil
                            completion:^(BOOL b)
                            {
                                [to didMoveToParentViewController:self];
                                [from.view removeFromSuperview];
                                [from removeFromParentViewController];
                            }];
}