试试这个…它将工作....

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    self.title = ""
}

上面的代码将隐藏文本，只显示导航栏上的后退箭头。

解决方案检查和工作在Swift 5

下面是针对不同情况的一些解决方案:

1. 从后退按钮中删除文本

从后退按钮中删除文本的最佳解决方案是在viewDidLoad()中添加:

navigationItem.backBarButtonItem = UIBarButtonItem()

2. 在返回按钮上设置自己的文本

如果你想设置你自己的标题，可以通过设置backButton的title:

let backButton = UIBarButtonItem()
backButton.title = "My Title"
navigationItem.backBarButtonItem = backItem

3.清空所有VC上的返回按钮

如果你想在整个应用程序中创建通用样式-只有箭头返回而没有文本，为所有的视图控制器创建基础VC:

class BaseViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()

        navigationItem.backBarButtonItem = UIBarButtonItem()
    }
}

上面给出的解决方案可以让你在将来自定义返回按钮，如果你以后想要做一些例外，通过添加额外的变量并在特定的ViewController中重写它，f.x:

class BaseViewController: UIViewController {

    var customBackButtonTitle: String?

    override func viewDidLoad() {
        super.viewDidLoad()

        var backButton = UIBarButtonItem()
        if let text = customBackButtonTitle {
            backButton.title = text
        }
        navigationItem.backBarButtonItem = backButton
    }
}

这应该可以工作:

override func viewDidLoad() {
    super.viewDidLoad()

    var button = UIBarButtonItem(title: "YourTitle", style: UIBarButtonItemStyle.Bordered, target: self, action: "goBack")
    self.navigationItem.backBarButtonItem = button

}

func goBack()
{
    self.navigationController?.popViewControllerAnimated(true)
}

虽然不建议这样做，因为这实际上取代了backButton，它也删除了后退箭头和滑动手势。

虽然这些答案解决了问题，但这可能是一些有用的

class MainNavigatioController: UINavigationController {

    override func pushViewController(_ viewController: UIViewController, animated: Bool) {
        // first
        let backItem = UIBarButtonItem()
        backItem.title = "رجوع"
        self.viewControllers.last?.navigationItem.backBarButtonItem = backItem
        // then
        super.pushViewController(viewController, animated: animated)

    }

}

在呈现控制器的viewDidLoad方法中添加:

// hide navigation bar title in the next controller
let backButton = UIBarButtonItem(title: "", style:.Plain, target: nil, action: nil)
navigationItem.backBarButtonItem = backButton

back按钮属于前一个视图控制器，而不是当前显示在屏幕上的那个。 要修改返回按钮，你应该在按之前更新它，在启动segue的视图控制器上:

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    let backItem = UIBarButtonItem()
    backItem.title = "Something Else"
    navigationItem.backBarButtonItem = backItem // This will show in the next view controller being pushed
}

Swift 3,4和5:

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    let backItem = UIBarButtonItem()
    backItem.title = "Something Else"
    navigationItem.backBarButtonItem = backItem // This will show in the next view controller being pushed
}

OR

// in your viewDidLoad or viewWillAppear
navigationItem.backBarButtonItem = UIBarButtonItem(
    title: "Something Else", style: .plain, target: nil, action: nil)