ios - 在 UINavigationBar 上使用左侧的标准箭头创建自定义左后退按钮

Question

创建自定义后退按钮时，我使用以下代码：

    UIBarButtonItem *leftButton = [[UIBarButtonItem alloc]initWithTitle:@"Yeah" style:UIBarButtonItemStyleBordered target:self action:@selector(backButtonPressed:)];
self.navigationItem.leftBarButtonItem = leftButton;

这很好用，我得到了这个结果：

我会得到相同的结果，但左侧有一个箭头，如下所示（当它是标准后退按钮，而不是自定义按钮时）：

我怎样才能简单地添加这个箭头？

Answer 1

最后，这是我用来在当前视图中使用标准左箭头定义后退按钮标题的片段，而不是在父视图中：

- (void)viewDidLoad {
    [super viewDidLoad];

    [self setTitle:@"Current View"];

    // Get the previous view controller
    UIViewController *previousVC = [self.navigationController.viewControllers objectAtIndex:self.navigationController.viewControllers.count - 2];

    // Create a UIBarButtonItem
    UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"FooBar" style:UIBarButtonItemStyleBordered target:self action:@selector(yourSelector)];

    // Associate the barButtonItem to the previous view
    [previousVC.navigationItem setBackBarButtonItem:barButtonItem];
}

---

结果如下：

注意：但是，由于无法在 backBarButtonItem 上添加操作，因此如果您愿意，可以参考这篇很棒的帖子。

为 Swift 更新

// Prev - no chevron...
//navigationItem.leftBarButtonItem = UIBarButtonItem(title: "Back !", style: .plain, target: self, action: #selector(backPressed))

// adds the chevron
let vc = navigationController?.viewControllers.first
let button = UIBarButtonItem(title: "Go Back", style: .plain, target: self, action: #selector(backPressed))
vc?.navigationItem.backBarButtonItem = button

Answer 2

最简单的做法是在父控制器中设置标题（即您想要导航回的那个）。如果您不希望这与该 VC 视图中显示的实际标题相同，您可以将 viewWillDisappear 中的标题更改为下一个 VC 的后退按钮上所需的标题，然后将其更改回您想要的父视图将出现。

如果你使用storyboards，你也可以直接在IB中设置back title。

最后，为了创建自定义后退按钮，您可以执行以下操作：

self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc]initWithTitle:@"Details" style:UIBarButtonItemStyleBordered target:nil action:nil];

...只需确保在呈现（或父）视图控制器中执行此操作，而不是正在加载的视图控制器（呈现的控制器）。

Answer 3

UIButton * backButton = [UIButton buttonWithType:UIButtonTypeCustom];
[backButton addTarget:self action:@selector(popViewController) forControlEvents:UIControlEventTouchUpInside];
[backButton setFrame:FRAME_DEFINE
[backButton setContentHorizontalAlignment:UIControlContentHorizontalAlignmentLeft];
[backButton setExclusiveTouch:YES];
[backButton setImage:[UIImage imageNamed:BACK_BUTTON_DEFAULT_ICON] forState:UIControlStateNormal];
[backButton setTitle:@"BACK" forState:UIControlStateNormal];
[backButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
UIBarButtonItem *backMenuBarButton = [[UIBarButtonItem alloc] initWithCustomView:backButton];
self.navigationItem.leftBarButtonItem = backMenuBarButton;

Answer 4

好吧，您需要使用背景图像和标题

// Creates a back button instead of default behaviour (displaying title of previous screen)
UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"back_arrow.png"]
                                                               style:UIBarButtonItemStyleBordered
                                                              target:self
                                                              action:@selector(backAction)];

tipsDetailViewController.navigationItem.leftBarButtonItem = backButton;
[backButton release];

Answer 5

我使用如下代码：

UIBarButtonItem *leftBar = [[UIBarButtonItem alloc] init];
leftBar.title = @"Back";//Details
self.navigationController.navigationBar.topItem.backBarButtonItem = leftBar;

Answer 6

对于 Swift，以 Erzekiel 的回答为基础，您可以将其简化为 -

extension UIViewController {

    func setBackButtonTitle(to title: String) {
        let barButtonItem = UIBarButtonItem(title: title, style: .plain, target: self, action: nil)
        self.navigationItem.backBarButtonItem = barButtonItem
    }
}

这应该从父视图控制器调用，例如在 viewWillDisappear -

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    self.setBackButtonTitle(to: "Back"))
}