UINavigationBar 后退按钮标题无法使用 iOS 13 的导航栏外观删除

Question

在我的应用程序中，我想删除 UINavigationBar 后退按钮标题。 我已经完成了以下代码

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
     // do other staffs 
     initNavigationBar()

     return true 

}

private func initNavigationBar() {

        let appearance = UINavigationBar.appearance()
        appearance.barTintColor = GLOBAL_TINT_COLOR // a globally declared colour 
        appearance.tintColor = .white
        appearance.barStyle = .black

        if #available(iOS 13.0, *) {
            let backButtonAppearance = UIBarButtonItemAppearance()
            backButtonAppearance.normal.titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.clear]
            appearance.standardAppearance.backButtonAppearance = backButtonAppearance
            appearance.compactAppearance?.backButtonAppearance = backButtonAppearance
            appearance.scrollEdgeAppearance?.backButtonAppearance = backButtonAppearance
        } else {


            // Hide navigation bar back button items

            UIBarButtonItem.appearance(whenContainedInInstancesOf: [UINavigationBar.self]).setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.clear], for: .normal)

            UIBarButtonItem.appearance(whenContainedInInstancesOf: [UINavigationBar.self]).setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.clear], for: .highlighted)
        }

}

但是，此代码始终适用于 iOS 10-12，但不适用于 iOS 13。我错过了什么吗？

在其他情况下，我找到了很多关于该主题的答案，但没有找到iOS 13的解决方案

我从不想使用set back button title as an empty string，而不是使用外观来修复它。

谢谢

Answer 1

几周前我遇到了类似的问题。我没有找到针对整个应用程序全局执行此操作的方法，因此我求助于自定义每个导航控制器（幸好并不多）。

我通过扩展 UINavigationController 做了类似的事情：

@available(iOS 13, *)
func hideBackButton() {
    let appearance = self.navigationBar.standardAppearance

    let hideBackButtonTitleAttributes: [NSAttributedString.Key: Any] = [
        .foregroundColor: UIColor.clear
    ]

    let normalBackButton = appearance.backButtonAppearance.normal
    let highlightedBackButton = appearance.backButtonAppearance.highlighted

    normalBackButton.titleTextAttributes = hideBackButtonTitleAttributes
    highlightedBackButton.titleTextAttributes = hideBackButtonTitleAttributes

    navigationBar.standardAppearance = appearance
}

然后我像这样使用hideBackButton 方法：

navigationController?.hideBackButton()

如果对整个应用程序有更好的方法，请告诉我。

Answer 2

您可以将您的后备项目设置为没有这样的标题：

self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:nil style:UIBarButtonItemStylePlain target:nil action:nil];

请注意，这会影响将其他内容推送到导航堆栈时显示的内容。如果您将视图控制器 A 设置为导航控制器的根并像这样设置 A 的后项，则当您将视图控制器 B 推入堆栈时，您会看到它。设置 B 的后退项不会影响 B 可见时您在后退项中看到的内容。

Answer 3

我已经添加了 ios15 移除 BackBar 按钮标题和设置导航：

    if #available(iOS 15, *) {
        let appearance = UINavigationBarAppearance()
        let pargraphStyle = NSMutableParagraphStyle()
        pargraphStyle.alignment = .center
        let fontApply = UIFont.bold(size: 18)
        UINavigationBar.appearance().tintColor = UIColor.themeColor
        appearance.configureWithOpaqueBackground()
        appearance.backgroundColor = UIColor.black
        appearance.titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.themeColor, NSAttributedString.Key.font: fontApply, NSAttributedString.Key.paragraphStyle: pargraphStyle]
        appearance.shadowImage = nil
        appearance.shadowColor = .clear
        UINavigationBar.appearance().barStyle = .default
        UINavigationBar.appearance().tintColor = UIColor.themeColor
        UINavigationBar.appearance().isTranslucent = false
        UINavigationBar.appearance().backIndicatorImage = #imageLiteral(resourceName: "BackIcon")
        UINavigationBar.appearance().backIndicatorTransitionMaskImage = #imageLiteral(resourceName: "BackIcon")
        UINavigationBar.appearance().standardAppearance = appearance
        UINavigationBar.appearance().scrollEdgeAppearance = appearance
        
        // Set Back Bar Button Appearance
        let appearanceBackButton = UIBarButtonItemAppearance()

        let hideBackButtonTitleAttributes: [NSAttributedString.Key: Any] = [
            .foregroundColor: UIColor.clear
        ]

        let normalBackButton = appearance.backButtonAppearance.normal
        let highlightedBackButton = appearance.backButtonAppearance.highlighted

        normalBackButton.titleTextAttributes = hideBackButtonTitleAttributes
        highlightedBackButton.titleTextAttributes = hideBackButtonTitleAttributes
        appearance.buttonAppearance = appearanceBackButton
    
    }