iOS 7 自定义过渡问题

Question

我正在尝试在 iPad 上实现一些自定义转换，但我遇到了一些问题。由于X，Y坐标不总是在左上角开始containerView的transitionContext，当设备旋转我写了下面的方法

- (CGRect)rectForPresentedStateStart:(id<UIViewControllerContextTransitioning>)transitionContext
{
    UIViewController *fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
    UIView *containerView = [transitionContext containerView];
    
    switch (fromViewController.interfaceOrientation)
    {
        case UIInterfaceOrientationLandscapeRight:
            return CGRectMake(0, containerView.bounds.size.height,
                              containerView.bounds.size.width, containerView.bounds.size.height * 2 / 3);
        case UIInterfaceOrientationLandscapeLeft:
            return CGRectMake(0, - containerView.bounds.size.height * 2 / 3,
                              containerView.bounds.size.height, containerView.bounds.size.height * 2 / 3);
        case UIInterfaceOrientationPortraitUpsideDown:
            return CGRectMake(- containerView.bounds.size.width * 2 / 3, 0,
                              containerView.bounds.size.width * 2 / 3, containerView.bounds.size.height);
        case UIInterfaceOrientationPortrait:
            return CGRectMake(containerView.bounds.size.width, 0,
                              containerView.bounds.size.width * 2 / 3, containerView.bounds.size.height);
        default:
            return CGRectZero;
    }

}

- (CGRect)rectForPresentedStateEnd:(id<UIViewControllerContextTransitioning>)transitionContext
{
    UIViewController *toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
    UIView *containerView = [transitionContext containerView];

    
    switch (toViewController.interfaceOrientation)
    {
        case UIInterfaceOrientationLandscapeRight:
            return CGRectOffset([self rectForPresentedStateStart:transitionContext], 0, - containerView.bounds.size.height * 2 / 3);
        case UIInterfaceOrientationLandscapeLeft:
            return CGRectOffset([self rectForPresentedStateStart:transitionContext], 0, containerView.bounds.size.height * 2 / 3);
        case UIInterfaceOrientationPortraitUpsideDown:
            return CGRectOffset([self rectForPresentedStateStart:transitionContext], containerView.bounds.size.width * 2 / 3, 0);
        case UIInterfaceOrientationPortrait:
            return CGRectOffset([self rectForPresentedStateStart:transitionContext], - containerView.bounds.size.width * 2 / 3, 0);
        default:
            return CGRectZero;
    }
}

在纵向模式和颠倒一切似乎工作正常。问题出在景观上。

1. 当设备方向为 时UIInterfaceOrientationLandscapeLeft，视图会在过渡开始前消失一秒钟。

2. 当设备方向为时，UIInterfaceOrientationLandscapeRight我遇到以下问题：导航栏变小并在过渡结束时变为正常，如图片所示

发生转换时导航栏出现问题

过渡完成后

我不确定这些是来自苹果的错误还是我做错了什么，如果是这样，我该如何解决这些问题？

Answer 1

这绝对是苹果的 bug。为了呈现动画，我使用的是这样的东西：

if (self.presenting) {
        toViewController.view.frame = [self rectForPresentedStateStart:transitionContext];
        [transitionContext.containerView addSubview:toViewController.view];
        [UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
            fromViewController.view.frame = [self rectForDismissedState:transitionContext];
            toViewController.view.frame = [self rectForPresentedStateEnd:transitionContext];
        } completion:^(BOOL finished) {
            [transitionContext completeTransition:YES];
        }];    
}

[transitionContext.containerView addSubview:toViewController.view]; 如果我在方法后面添加视图 ( )，导航控制器的问题就可以解决 animateWithDuration。仍然不明白为什么。