后退按钮导航栏不改变图像 swift

Question

我有一个导航 controller 在其中创建了导航栏，现在当我将 go 切换到新屏幕时，我想更改导航的左侧图标。 但它不起作用

    var wwwe = TPCustomNavigationViewController()

override func viewDidLoad() {
    super.viewDidLoad()
    self.wwwe.backButton?.setImage(#imageLiteral(resourceName: "arrow_gray_sx"), for: .normal)
    self.wwwe.backButton?.setImage(#imageLiteral(resourceName: "arrow_gray_sx"), for: .selected)

    guard let url = URL(string: "https://toduba-website-test.clikapp.vercel.app/helpdesk") else {
        return
    }
    let request = URLRequest(url: url)
    webview?.load(request)
}

Answer 1

您好，要访问您的导航栏项目，您可以这样进行

let img = UIImage(named: "navbar-image")
navigationController?.navigationBar.setBackgroundImage(img, for: .default)

Answer 2

好的解决了这个

    override func viewWillAppear(_ animated: Bool) {
    (self.navigationController as? TPCustomNavigationViewController)?.backButton?.setImage(#imageLiteral(resourceName: "arrow_gray_sx"), for: .normal)
    (self.navigationController as? TPCustomNavigationViewController)?.backButton?.setImage(#imageLiteral(resourceName: "arrow_gray_sx"), for: .selected)
}