如何从超级超级视图中删除自身和超级视图？

Question

I have a UIViewController classes A and B . A loads B using: [A.view addSubView B.view] .

B has a navigation bar with a Back button. I want to go back to A when I click it, so in the selector I tried [self.view removeFromSuperview] , but it only removed the navigation bar. Then I tried [self.view.superview removeFromSuperview] , it still just removed the navigation bar. What should I do?

Also, another minor issue with the Back button: setting it's title. I tried these two ways, but it still displays "Back".

navItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Chapter" style:UIBarButtonItemStylePlain target:self action:@selector(handleBackBarButtonItem:)];

navItem.backBarButtonItem.title = @"Chapter";

Thank you in advance!

Answer 1

I don't think you quite understand how navigation (with UINavigationController ) works in iOS. Assuming you want animation, this is what you want:

1. Set up a UINavigationController . This can be done in the app's delegate (to avoid memory leakage, set an instance variable on UINavigationController *navController :

    navController = [[UINavigationController alloc] initWithRootViewController:A]; 

   Note that we are adding A as our root view controller.

2. Push the second view controller when needed. I assume that you are adding B.view after a button is clicked or something. In the implementation of the method that adds the second view controller, run the following code, instead of [A.view addSubview:B.view] . This method should be in the first controller's .m file:

    [self.navigationController pushViewController:B animated:YES]; 

   This will also give a nice transition effect.

3. Pop the second view controller off the stack. With UINavigationController , a pretty arrow-shaped back button is automatically included in a pushed view controller, to navigate back to the last view controller. This means that you don't even need any code to allow backward navigation.

That's it! Now if you need to change the title of B 's back button, do this in A 's viewDidLoad method:

self.navigationItem.backBarButtonItem = customBackButtonItem;

Answer 2

You can get an array of subviews and then remove the ones you wanted to be removed. This SO post will show you how to remove all subviews or multiple subviews using subviews array.