NavigationBar更改颜色本身

Question

我有两个风投。在这两个地方我都写了NavigationController外观的代码，但是当我从第二个VC返回到第一个时，我得到了所有的东西都是黑色的……

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first VC时，它不能从viewDidLoad加载颜色呢？

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Answer 1

因为已经加载了第一个ViewController，所以将导航栏设置放在viewWillAppear中

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)
}