pushviewcontroller animation is slow/choppy

Question

I push a ViewController which contains not too many views, UIScrollView which contains 10 views inside, I have a singleton ViewController

Answer 1

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;

}