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;
}