gistfile1.m

- (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext
{
    if ([self.delegate respondsToSelector:@selector(setAnimating:)])
        [self.delegate setAnimating:YES];
    
    UIView* containerView = [transitionContext containerView];
    
    UIViewController* fromVC = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
    UIViewController* toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
    
    if (fromVC && toVC)
    {
        if (UINavigationControllerOperationPop == self.operation)
        {
            CGRect frame = containerView.bounds;
            frame.origin.x = frame.size.width;
    
            toVC.view.frame = containerView.bounds;
            fromVC.view.frame = containerView.bounds;

            [containerView addSubview:toVC.view];
            [containerView bringSubviewToFront:fromVC.view];
            [containerView sendSubviewToBack:toVC.view];
            
            UIView* contentMask = [toVC.view viewWithTag:kContentMaskKey];
            
            if (nil == contentMask)
            {
                contentMask = [[UIView alloc] initWithFrame:containerView.bounds];
                [toVC.view addSubview:contentMask];
            }
            
            contentMask.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.85f];
            
            CATransform3D transform = CATransform3DIdentity;
            transform.m34 = 1.0f / - 500.0f;
            transform = CATransform3DTranslate(transform, 0.0f, 0.0f, -40.0f);
            toVC.view.layer.transform = transform;
            
            [UIView animateWithDuration:kTransitionDuration
                                  delay:0.0f
                                options:0
                             animations:^{
                                 
                                 contentMask.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.0f];
                                 
                                 [UIView addKeyframeWithRelativeStartTime:0.0
                                                         relativeDuration:kTransitionDuration/2
                                                               animations:^{
                                                                   fromVC.view.frame = frame;
                                                               }];
                                 
                                 [UIView addKeyframeWithRelativeStartTime:kTransitionDuration/2
                                                         relativeDuration:kTransitionDuration/2
                                                               animations:^{
                                                                   toVC.view.layer.transform = CATransform3DIdentity;
                                                               }];
                                 
                             }
                             completion:^(BOOL finished) {
                                 
                                 [fromVC.view removeFromSuperview];
                                 
                                 [transitionContext completeTransition:finished];
                                 
                             }];
        
        }
        else if (self.operation == UINavigationControllerOperationPush)
        {
            CGRect frame = containerView.bounds;
            frame.origin.x = frame.size.width;
            toVC.view.frame = frame;
            fromVC.view.frame = containerView.bounds;
            
            [containerView addSubview:toVC.view];
            [containerView bringSubviewToFront:toVC.view];
            [containerView sendSubviewToBack:fromVC.view];
            
            UIView* contentMask = [fromVC.view viewWithTag:kContentMaskKey];
            
            if (nil == contentMask)
            {
                contentMask = [[UIView alloc] initWithFrame:containerView.bounds];
                [fromVC.view addSubview:contentMask];
            }
            
            contentMask.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.0f];
                        
            [UIView animateWithDuration:kTransitionDuration
                                  delay:0.0f
                                options:0
                             animations:^{
                                 
                                 contentMask.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.85f];
                                 
                                 [UIView addKeyframeWithRelativeStartTime:0.0
                                                         relativeDuration:kTransitionDuration/2
                                                               animations:^{
                                                                   toVC.view.frame = containerView.bounds;
                                                               }];
                                 
                                 [UIView addKeyframeWithRelativeStartTime:kTransitionDuration/2
                                                         relativeDuration:kTransitionDuration/2
                                                               animations:^{
                                                                   
                                                                   CATransform3D transform = CATransform3DIdentity;
                                                                   transform.m34 = 1.0f / - 500.0f;
                                                                   transform = CATransform3DTranslate(transform, 0.0f, 0.0f, -40.0f);
                                                                   fromVC.view.layer.transform = transform;
                                                               }];
                                 
                             }
                             completion:^(BOOL finished) {
                                 
                                 [fromVC.view removeFromSuperview];
                                 [transitionContext completeTransition:finished];
                             }];
        }
        else
        {
            
        }
    }
    else if (toVC)
    {
        toVC.view.frame = containerView.bounds;
        [containerView addSubview:toVC.view];
        [transitionContext completeTransition:YES];
    }
}