NavigationBar更改颜色本身

Question

我有2个VC。 在这两种代码中，我都将代码编写为NavigationController的外观，但是当我从第二个VC返回第一个VC时，一切都变黑了……

第一个VC：

override func viewDidLoad() {
        super.viewDidLoad()

        self.navigationController?.navigationBar.isTranslucent = true
        self.navigationController?.navigationBar.barTintColor = UIColor.white
        self.navigationController?.navigationBar.titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.black]
        self.navigationController?.navigationBar.largeTitleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.black]
        self.navigationController?.navigationBar.tintColor = UIColor.init(red:47/255.0, green:158/255.0, blue:249/255.0, alpha: 1.0)
}

第二个VC：

self.navigationController?.navigationBar.isTranslucent = false
        self.navigationController?.navigationBar.barTintColor = UIColor.black
        self.navigationController?.navigationBar.titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
        self.navigationController?.navigationBar.largeTitleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
        self.navigationController?.navigationBar.tintColor = UIColor.white

那么为什么当我回到第一个VC时它不从viewDidLoad中加载颜色呢？

Answer 1

因为您的第一个ViewController已经加载，所以将导航栏设置放入viewWillAppear

override func viewWillAppear() {
    super. viewWillAppear()

    self.navigationController?.navigationBar.isTranslucent = true
    self.navigationController?.navigationBar.barTintColor = UIColor.white
    self.navigationController?.navigationBar.titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.black]
    self.navigationController?.navigationBar.largeTitleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.black]
    self.navigationController?.navigationBar.tintColor = UIColor.init(red:47/255.0, green:158/255.0, blue:249/255.0, alpha: 1.0)
}