iphone - Add child view controller to UINavigationController

Question

I'm trying to add a child view controller to a UIViewController contained in a UINavigationController with this code:

- (void)buttonTapped:(id)sender
{
    MyChildController *viewController = [self.storyboard instantiateViewControllerWithIdentifier:@"MyChild"];
    [self addChildViewController:viewController];
    [self.view addSubview:viewController.view];
    [viewController didMoveToParentViewController:self];


    viewController.view.alpha = 0.0f;
    [UIView animateWithDuration:0.4 animations:^{
        viewController.view.alpha = 1.0f;
    }];
}

But this is the result:

As you can see the UINavigatioBar and the UIToolbar are still on top of the child view controller. How can I put the child view controller on top of all? I've already tried to replace the code with:

[self.navigationController addChildViewController:viewController];
    [self.navigationController.view addSubview:viewController.view];
    [viewController didMoveToParentViewController:self.navigationController];

But in this way the viewDidAppear:animated of the viewController doesn't get called. I don't know, why.

Answer 1

@Sam的评论是正确的。您需要调用beginApperanceTransition:animated:并被触发endAppearanceTransition。viewDidAppear之所以在添加子视图控制器时UINavigationController不调用viewDidAppear，是因为它已经覆盖了它的容器组合方法，以防止程序员在陌生的地方添加子视图控制器。在您的情况下，它不希望您的子视图覆盖导航栏。导航控制器的正确用法是让孩子出现在导航栏下方。尽管如此，您仍然可以通过手动告诉孩子何时出现以及何时完成出现来强制使用此非标准 UI。

向 UINavigationController 添加一个孩子

MyChildViewController* child = [[MyChildViewController alloc] init];
[self.navigationController addChildViewController:child];
child.view.frame = self.navigationController.view.bounds;
[self.navigationController.view addSubview:child.view];
child.view.alpha = 0.0;
[child beginAppearanceTransition:YES animated:YES];
[UIView
    animateWithDuration:0.3
    delay:0.0
    options:UIViewAnimationOptionCurveEaseOut
    animations:^(void){
        child.view.alpha = 1.0;
    }
    completion:^(BOOL finished) {
        [child endAppearanceTransition];
        [child didMoveToParentViewController:self.navigationController];
    }
];

从 UINavigationController 中删除一个孩子

[child willMoveToParentViewController:nil];
[child beginAppearanceTransition:NO animated:YES];
[UIView
    animateWithDuration:0.3
    delay:0.0
     options:UIViewAnimationOptionCurveEaseOut
    animations:^(void){
        child.view.alpha = 0.0;
    }
    completion:^(BOOL finished) {
        [child endAppearanceTransition];
        [child.view removeFromSuperview];
        [child removeFromParentViewController];
    }
];

Answer 2

在您的第一个视图控制器中，执行以下操作：

- (IBAction)buttonClick:(id)sender
{
    SecondViewController *secondView = [self.storyboard instantiateViewControllerWithIdentifier:@"SecondViewController"];
    UIImage *blurryImage = [UIImage imageNamed:@"foo.jpeg"];
    secondView.imageView.image = blurryImage;
    [self.navigationController addChildViewController:secondView];
    secondView.view.frame = self.navigationController.view.frame;
    [self.navigationController.view addSubview:secondView.view];
}

然后在你的第二个视图控制器中，为你的 imageview 添加 getter：

-(UIImageView *)imageView
{
    if( _imageView == nil )
    {
        _imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 320, 548)];
        [self.view addSubview:_imageView];
    }
    return _imageView;
}

Answer 3

@Pwner的回答 Swift 版本：

将孩子添加到 UINavigaitonController

let child = MyChildViewController()
self.navigationController?.addChildViewController(child)
guard let navigationController = navigationController else {
    return
}
child.view.frame = navigationController.view.bounds
child.beginAppearanceTransition(true, animated: true)
self.navigationController?.view.addSubview(child.view)
self.view.alpha = 0
UIView.animate(withDuration: 0.3, animations: {
    child.view.alpha = 1.0
}, completion: { _ in
    guard let navigationController = self.navigationController else {
        return
    }
    child.endAppearanceTransition()
    child.didMove(toParentViewController: navigationController)
})

从 UINavigationController 中删除一个孩子

child.willMove(toParentViewController: nil)
child.beginAppearanceTransition(false, animated: true)
UIView.animate(withDuration: 0.3, animations: {
    child.view.alpha = 0.0
}, completion: { _ in
    guard let navigationController = self.navigationController else {
        return
    }
    child.view.removeFromSuperview()
    child.endAppearanceTransition()
    child.removeFromParentViewController()
})