iOS 自定义Present转场动画，Dismiss后黑屏

黑屏.gif

出现这个黑屏的三个点：

1. FromVC设置了transitioningDelegate (UIViewControllerTransitioningDelegate)
2. FromVC.modalPresentationStyle = UIModalPresentationCustom
3. Dismiss的

-(void)animateTransition:(id)transitionContext{
    ...
    [containerView addSubview:toVC.view];
    ...
}

Fix：

-(void)animateTransition:(id)transitionContext{
    ...
    if (fromVC.modalPresentationStyle == UIModalPresentationFullScreen) {
        [containerView addSubview:toVC.view];
    }
    ...
}

violet.jpg