你可以用这个。把它放在AppDelegate.swift中。

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

        UINavigationBar.appearance().translucent = false
        UINavigationBar.appearance().barTintColor = UIColor(rgba: "#2c8eb5")
        UINavigationBar.appearance().tintColor = UIColor.whiteColor()
        UINavigationBar.appearance().titleTextAttributes = [NSForegroundColorAttributeName:UIColor.whiteColor()]

        return true
    }

在Swift 4中，你可以使用以下方法来解决这个问题:

let navStyles = UINavigationBar.appearance()
// This will set the color of the text for the back buttons.
navStyles.tintColor = .white
// This will set the background color for navBar
navStyles.barTintColor = .black

斯威夫特5.3:

UINavigationBar.appearance().backIndicatorImage = UIImage(named: "custom-back-image")
UINavigationBar.appearance().backIndicatorTransitionMaskImage = UIImage(named: "custom-back-image")

不知道为什么没有人提到这一点…但我所做的正是你在我的viewDidLoad中所做的…但它并没有起作用。然后我把我的代码放在viewWillAppear，它都工作了。

上面的解决方案是改变一个barbuttonItem。如果你想改变代码中每个navigationBar的颜色，那么遵循这个答案。

基本上，使用appearance()更改到类本身就像在应用程序中对该视图的所有实例进行全局更改。更多信息请参阅这里

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swift 2.0使用中

self.navigationController!.navigationBar.tintColor = UIColor.whiteColor();