在UINavigationController中为根视图制作返回按钮 [英] Making back button for root view in UINavigationController

问题描述

所以我手动创建了一个 UINavigationController ，将其设置为我的 UIWindow的 rootViewController，我想使用后退按钮退出 UINavigationController 并在其位置加载另一个viewController。但是， UINavigationBar 的 backItem 属性是 readonly ，因此我不知道如何正确设置它（它只是 readonly 并在根导航视图中默认为nil。我怎样才能实现这一点（或者类似的效果，我希望能够通过按下根视图上的后退按钮有效地退出这个 UINavigationController 。）

So I created a UINavigationController manually, set it as my UIWindow's rootViewController, and I would like to use a back button to exit the UINavigationController and load another viewController in its place. However, the backItem property of the UINavigationBar is readonly, so I don't know how to set it properly (it is readonly and defaults to nil in the root navigation view). How can I achieve this (or similar effect, I want to be able to effectively "exit" this UINavigationController by pressing the back button on the root view).

或者，这是不好的形式？我应该如何逃避 UINavigationController 的根视图？

Alternatively, is this bad form? How should I escape the root view of a UINavigationController?

编辑：

使用以下代码尝试Legolas的解决方案:(某些名称已更改）

Attempted Legolas' solution with the following code: (some names have been changed)

UINavigationController* navController = [[UINavigationController alloc] initWithRootViewController:plvc]; // plvc being the first viewcontroller
MyAppDelegate* appDelegate = [Utility getAppDelegate];
appDelegate.window.rootViewController = navController;

UIBarButtonItem* backButton = [[UIBarButtonItem alloc] initWithTitle:@"Start" style:UIBarButtonItemStyleBordered target:self action:@selector(initializeStuff)];
navController.navigationItem.leftBarButtonItem = backButton;
[navController.navigationItem setHidesBackButton:YES animated:YES];
[navController.view setNeedsDisplay];

但按钮不显示。我究竟做错了什么？其他后退按钮显示正常，但这个按钮仍然没有显示。

But the button does not display. What am I doing wrong? The other back buttons display properly, but this one still does not.

推荐答案

您可以采用不同的方法。

You can do this in a different approach.

转到方法：

- (void)viewDidLoad

隐藏后退按钮

[self.navigationItem setHidesBackButton:YES animated:YES];

创建一个新的UIButton或UIBarButtonItem，并将其放在后退按钮的位置。

Create a new UIButton or a UIBarButtonItem, and place it in place of the back button.

然后您可以在单击按钮时使用操作

You can then use an action when you click the button

- (IBAction) clickBackButton : (id) sender; //and push view controller to your required view.

更新我的答案：在viewDidLoad方法中使用//就像魅力//

Updating my answer: Use this in the viewDidLoad method //works like a charm //

[self.navigationItem setHidesBackButton:YES animated:YES];
UIBarButtonItem* backButton = [[UIBarButtonItem alloc] initWithTitle:@"Start" style:UIBarButtonItemStyleBordered target:self action:@selector(initializeStuff)];

self.navigationItem.leftBarButtonItem = backButton;

这篇关于在UINavigationController中为根视图制作返回按钮的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！