'''
原文出处/尊重作者
Objective-C改变push、pop动画为模态效果
'''
push：

CATransition *transition = [CATransition animation];
transition.duration = 0.4f;
transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
transition.type = kCATransitionMoveIn;
transition.subtype = kCATransitionFromTop;
transition.delegate = self;
[self.navigationController.view.layer addAnimation:transition forKey:nil];
[self.navigationController pushViewController:controller animated:NO];

pop：

CATransition *transition = [CATransition animation];
transition.duration = 0.3f;
transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
transition.type = kCATransitionReveal;
transition.subtype = kCATransitionFromBottom;
transition.delegate = self;
[self.navigationController.view.layer addAnimation:transition forKey:nil];
[self.navigationController popViewControllerAnimated:NO];

注意：animated一定要设置为：NO