从子视图导航控制器访问顶部导航控制器 [英] Accessing a Top Navigation Controller from a Subview Navigation Controller

问题描述

我的观点和控制器设置如此。

I have a my views and controllers set up like so.

1. 标签/栏控制器


2. 1.是根视图控制器


3. 2.是一个以编程方式创建的导航控制器，在根视图控制器中显示为子视图。

我要做的是访问顶部标签栏/导航控制器，以便我可以将视图推到它上面。

What I am trying to do is access the top tab bar/navigation controller so that i can push a view onto it.

我尝试过parentViewController，但它只是把视图推到了编程的导航控制器上。

I tried parentViewController but all it did was push the view onto the programmed nav controller.

有什么建议吗？

这就是我设置我的根视图控制器的方法：

This is how i set up my root view controller:

  -(void)viewDidAppear:(BOOL)animated{
    NSLog(@"ROOT APPEARED");
    [super viewDidAppear:animated];

    WorklistViewController *worklistController = [[WorklistViewController alloc]initWithNibName:@"WorklistView" bundle:[NSBundle mainBundle]];
    UINavigationController *worklistNavController = [[UINavigationController alloc] initWithRootViewController:worklistController];
    worklistNavController.navigationBar.barStyle = UIBarStyleBlackOpaque;
    worklistNavController.view.frame = watchlistView.frame;
    [worklistNavController.topViewController  viewDidLoad];
    [worklistNavController.topViewController  viewWillAppear:YES];
    [self.view addSubview:worklistNavController.view];

    GetAlertRequestViewController *alertsController = [[GetAlertRequestViewController alloc]initWithNibName:@"AlertsView" bundle:[NSBundle mainBundle]];
    UINavigationController *alertsNavController = [[UINavigationController alloc] initWithRootViewController:alertsController];
    alertsNavController.navigationBar.barStyle = UIBarStyleBlackOpaque;
    alertsNavController.view.frame = alertsView.frame;
    [alertsNavController.topViewController  viewDidLoad];
    [alertsNavController.topViewController  viewWillAppear:YES];
    [self.view addSubview:alertsNavController.view];
}

推荐答案

嵌套的ViewController（即，在由实际在NavController堆栈上的ViewController控制的视图内部，不能直接访问其父视图的控制器是其堆栈成员的UINavigationController。这是句子中的一个，但它的意义是：你不能从这里到达那里。

A nested ViewController (ie, inside a view controlled by a ViewController that's actually on the NavController stack) doesn't have direct access to the UINavigationController that its parent's view's controller is a stack member of. That's one MOUTHFUL of a sentence, but the sense of it is: you can't get there from here.

相反，你必须通过应用程序的NavController来获取App委托。

Instead you've got to get at the app's NavController via the App delegate.

YourAppDelegate *del = (YourAppDelegate *)[UIApplication sharedApplication].delegate;
[del.navigationController pushViewController:nextViewController animated:YES];

您正在使用您的UIApplication的单身人士（包含有关您的应用程序的各种有用信息），一个指向AppDelegate的.delegate属性，它包含对NavigationController的引用。

You're using your UIApplication's singleton (contains all sorts of good info about your app), which has a .delegate property pointing to the AppDelegate, and that contains a reference to the NavigationController.

这就是基于导航的应用程序Xcode模板设置NavController所有权的方式，无论如何。 YMMV如果你自己推出 - 虽然如果你这样做，你可能不需要问这个问题。

This is how the "Navigation-based Application" Xcode template sets up NavController ownership, anyway. YMMV if you rolled your own--though if you did, you probably wouldn't need to ask this question.

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