你应该这样使用:

navigationController?.navigationBar.barTintColor = .purple
navigationController?.navigationBar.tintColor = .white

出于某种原因，它在编程上不适合我。但是，在故事板中设置它每次都有效。

对于Swift 2.0，要更改导航栏的色调颜色，标题文本和后退按钮的色调颜色更改，请使用AppDelegate.swift中的以下命令

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

  // Override point for customization after application launch.


    //Navigation bar tint color change

    UINavigationBar.appearance().barTintColor = UIColor(red: 42/255.0, green: 140/255.0, blue: 166/255.0, alpha: 0.5)

    //Back button tint color change

    UINavigationBar.appearance().barStyle = UIBarStyle.Default
    UINavigationBar.appearance().tintColor =  UIColor(red: 204/255.0, green: 255/255.0, blue: 204/255.0, alpha: 1)

    //Navigation Menu font tint color change

    UINavigationBar.appearance().titleTextAttributes = [NSForegroundColorAttributeName: UIColor(red: 204/255.0, green: 255/255.0, blue: 204/255.0, alpha: 1), NSFontAttributeName: UIFont(name: "OpenSans-Bold", size: 25)!]//UIColor(red: 42/255.0, green: 140/255.0, blue: 166/255.0, alpha: 1.0)

    UIApplication.sharedApplication().statusBarStyle = UIStatusBarStyle.LightContent


    return true
}

在AppDelegate类中使用此代码，在didFinishLaunchingWithOptions中。

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {

UINavigationBar.appearance().tintColor = .white

}

你应该加上这一行

 self.navigationController?.navigationBar.topItem?.backBarButtonItem?.tintColor = .black

让我们试试这段代码:

 func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    // Override point for customization after application launch.

    let navigationBarAppearace = UINavigationBar.appearance()
    navigationBarAppearace.tintColor = UIColor.whiteColor()  // Back buttons and such
    navigationBarAppearace.barTintColor = UIColor.purpleColor()  // Bar's background color
    navigationBarAppearace.titleTextAttributes = [NSForegroundColorAttributeName:UIColor.whiteColor()]  // Title's text color

    self.window?.backgroundColor = UIColor.whiteColor()
    return true
}