ios - 从 UINavigationController 中使用自定义转换关闭 UIViewController 时出现黑屏

Question

我有一个 View Controller FromViewController，我希望它呈现一个带有自定义转换的 ToViewController。我已经为 to- 和 from-transitions 实现了 UIViewControllerAnimatedTransitioning，当我呈现和关闭 ToViewController 时，它都运行良好。

但是，如果我的 FromViewController 包含在 UINavigationController 中，当我关闭 ToViewController 时，我只会看到黑屏。

这是关闭时 UIViewControllerAnimatedTransitioning 中的代码:

- (void)animateTransition:(nonnull id<UIViewControllerContextTransitioning>)transitionContext {
    self.toViewController = (ToViewController *)
    [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
    UINavigationController *navigationController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
    self.fromViewController = (FromViewController *)navigationController.topViewController;
    self.containerView = transitionContext.containerView;

    [self.containerView insertSubview:self.fromViewController.view belowSubview:self.toViewController.view];

    // My animations go here

    // In the animation completion block I call:
    [transitionContext completeTransition:!transitionContext.transitionWasCancelled];  // this is when my screen goes black
}

我检查了该应用程序，似乎 UINavigationController 和 FromViewController 在关闭后都不在 View 层次结构中。

Answer 1

我想通了。问题是当我将 View 添加到转换上下文容器 View 时:

 [self.containerView insertSubview:self.fromViewController.view belowSubview:self.toViewController.view];

相反，我需要从导航 Controller 添加 View :

[self.containerView insertSubview:navigationController.view belowSubview:self.toViewController.view];