Restore pre-iOS7 UINavigationController pushViewCo

Question

So. Just started transitioning my IOS code to IOS7, and ran into a bit of problem.

I've got a UINavigationController, which has child ViewControllers and I'm using pushViewController to display the next views. To create a parallax animation with a set of images, if customized the UINavigationController to animate a set of UIImageViews and my child ViewControllers all have a self.backgroundColor = [UIColor clearColor], transparency.

Since iOS7, the way the UINavController animates it child vc's, is updated, by partially moving the current view controller and on top pushing the new viewcontroller, my parallax animation looks crap. I see the previous VC move a bit and then disappear. Is there any way I can restore the previous UINavigationController pushViewController animation? I can't seem to find this in the code.

WelcomeLoginViewController* welcomeLoginViewController = [self.storyboard instantiateViewControllerWithIdentifier:@"WelcomeLogin"];
    [self.navigationController pushViewController:welcomeLoginViewController animated:YES];    

Even tried using:

    [UIView animateWithDuration:0.75
                     animations:^{
                         [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
                         [self.navigationController pushViewController:welcomeLoginViewController animated:NO];
                         [UIView setAnimationTransition:<specific_animation_form> forView:self.navigationController.view cache:NO];
                     }];

Does anyone have any clue?

Answer 1

I voted for @Arne's answer, because I find it the most elegant solution to this problem. I would just like to add some code in order to answer to @Bill's problem from his comment on @Arne's solution. Here's comment quote:

Thanks, this works for me. However, when the user taps the Back button, it reverts to the busted animation (because the back button doesn't call popViewControllerRetro). – Bill Oct 3 at 12:36

In order to call popViewControllerRetro when back button is pressed, there's a small hack you can perform in order to achieve this. Go into your pushed view controller, import UIViewController+Retro.h and add this code in your viewWillDisappear method:

- (void)viewWillDisappear:(BOOL)animated {
    if ([self.navigationController.viewControllers indexOfObject:self] == NSNotFound) {
        [self.navigationController popViewControllerRetro];
    }

    [super viewWillDisappear:animated];
}

This if statement will detect when Back button is pressed and will call popViewControllerRetro from category class.

Best regards.

Answer 2

First of, I'm not using Storyboard. I tried using UINavigationController+Retro. For some reason, the UINavigationController is having a hard time releasing the UIViewController at the top of the stack. Here's the solution that works for me using iOS 7 custom transition.

1. Set delegate to self.

   navigationController.delegate = self;
   

2. Declare this UINavigationControllerDelegate.

   - (id<UIViewControllerAnimatedTransitioning>)navigationController (UINavigationController *)navigationController 
   animationControllerForOperation:(UINavigationControllerOperation)operation
   fromViewController:(UIViewController *)fromVC 
   toViewController:(UIViewController *)toVC 
   {
       TransitionAnimator *animator = [TransitionAnimator new]; 
       animator.presenting = YES;
       return animator;
   }
   

   Note that it'll only get called when animated is set to YES. For example

   [navigationController pushViewController:currentViewController animated:YES];
   

3. Create the animator class extending NSObject. I called mine TransitionAnimator, which was modified from TeehanLax's TLTransitionAnimator inside UIViewController-Transitions-Example.

   TransitionAnimator.h

   #import <Foundation/Foundation.h>
   @interface TransitionAnimator : NSObject <UIViewControllerAnimatedTransitioning>
   @property (nonatomic, assign, getter = isPresenting) BOOL presenting;
   @end
   

   TransitionAnimator.m

   #import "TransitionAnimator.h"
   @implementation TransitionAnimator
   - (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext {
       return 0.5f;
   }
   - (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext{
       UIViewController *fromVC = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
       UIViewController *toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];    
       if (self.presenting) {
           //ANIMATE VC ENTERING FROM THE RIGHT SIDE OF THE SCREEN
           [transitionContext.containerView addSubview:fromVC.view];
           [transitionContext.containerView addSubview:toVC.view];     
           toVC.view.frame = CGRectMake(0, 0, 2*APP_W0, APP_H0); //SET ORIGINAL POSITION toVC OFF TO THE RIGHT                
           [UIView animateWithDuration:[self transitionDuration:transitionContext] 
               animations:^{
                   fromVC.view.frame = CGRectMake(0, (-1)*APP_W0, APP_W0, APP_H0); //MOVE fromVC OFF TO THE LEFT
                   toVC.view.frame = CGRectMake(0, 0, APP_W0, APP_H0); //ANIMATE toVC IN TO OCCUPY THE SCREEN
               } completion:^(BOOL finished) {
                   [transitionContext completeTransition:YES];
               }];
       }else{
           //ANIMATE VC EXITING TO THE RIGHT SIDE OF THE SCREEN
       }
   }
   @end
   

   Use presenting flag to set the direction you want to animate or which ever condition you prefer. Here's the link to Apple reference.

Answer 3

Found another great resource to help out:

http://www.teehanlax.com/blog/custom-uiviewcontroller-transitions

Using iOS7 TLTransitionAnimator to create custom animations

Answer 4

I had a problem where when UIViewController A did a pushViewController to push UIViewController B, the push animation would stop at about 25%, halt, and then slide B in the rest of the way.

This DID NOT happen on iOS 6, but as soon as I started using iOS 7 as the base SDK in XCode 5, this started happening.

The fix is that view controller B did not have a backgroundColor set on its root view (the root view is the one that is the value of viewController.view, that you typically set in loadView). Setting a backgroundColor in that root view's initializer fixed the problem.

I managed to fix this as follows:

// CASE 1: The root view for a UIViewController subclass that had a halting animation

- (id)initWithFrame:(CGRect)frame

{

     if ((self = [super initWithFrame:frame])) {

          // Do some initialization ...

          // self.backgroundColor was NOT being set

          // and animation in pushViewController was slow and stopped at 25% and paused

     }

     return self;

}

// CASE 2: HERE IS THE FIX

- (id)initWithFrame:(CGRect)frame

{

     if ((self = [super initWithFrame:frame])) {

          // Do some initialization ...

          // Set self.backgroundColor for the fix!

          // and animation in pushViewController is no longer slow and and no longer stopped at 25% and paused

          self.backgroundColor = [UIColor whiteColor]; // or some other non-clear color

     }

     return self;

}

Answer 5

I managed to workaround the new transition type by creating a category for UINavigationController. In my case I needed to revert it to the old transition style because I have transparent viewControllers that slide over a static background.

• UINavigationController+Retro.h

  @interface UINavigationController (Retro)
  
  - (void)pushViewControllerRetro:(UIViewController *)viewController;
  - (void)popViewControllerRetro;
  
  @end
  

• UINavigationController+Retro.m

  #import "UINavigationController+Retro.h"
  
  @implementation UINavigationController (Retro)
  
  - (void)pushViewControllerRetro:(UIViewController *)viewController {
      CATransition *transition = [CATransition animation];
      transition.duration = 0.25;
      transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
      transition.type = kCATransitionPush;
      transition.subtype = kCATransitionFromRight;
      [self.view.layer addAnimation:transition forKey:nil];
  
      [self pushViewController:viewController animated:NO];
  }
  
  - (void)popViewControllerRetro {
      CATransition *transition = [CATransition animation];
      transition.duration = 0.25;
      transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
      transition.type = kCATransitionPush;
      transition.subtype = kCATransitionFromLeft;
      [self.view.layer addAnimation:transition forKey:nil];
  
      [self popViewControllerAnimated:NO];
  }
  
  @end
  

Answer 6

Simply add in:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

This:

[[self window] setBackgroundColor:[UIColor whiteColor]];

The final result:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions (NSDictionary *)launchOptions {    
    [[self window] setBackgroundColor:[UIColor whiteColor]];

    // Override point for customization after application launch.
    return YES;
}