SWIFT 4 -平滑过渡(最佳解决方案):

如果你从导航控制器向后移动你必须在你想要使用的导航控制器上设置不同的颜色

override func willMove(toParentViewController parent: UIViewController?) {
    navigationController?.navigationBar.barTintColor = .white
    navigationController?.navigationBar.tintColor = Constants.AppColor
}

而不是把它放在viewWillAppear中，这样转换就更干净了。

斯威夫特4.2

override func willMove(toParent parent: UIViewController?) {
    navigationController?.navigationBar.barTintColor = UIColor.black
    navigationController?.navigationBar.tintColor = UIColor.black
}

斯威夫特4:

在应用程序级别更改导航栏外观的完美代码。

// MARK: Navigation Bar Customisation

// To change background colour.
UINavigationBar.appearance().barTintColor = .init(red: 23.0/255, green: 197.0/255, blue: 157.0/255, alpha: 1.0)

// To change colour of tappable items.
UINavigationBar.appearance().tintColor = .white

// To apply textAttributes to title i.e. colour, font etc.
UINavigationBar.appearance().titleTextAttributes = [.foregroundColor : UIColor.white,
                                                    .font : UIFont.init(name: "AvenirNext-DemiBold", size: 22.0)!]
// To control navigation bar's translucency.
UINavigationBar.appearance().isTranslucent = false

编码快乐!

这里有一些非常基本的外观定制，你可以应用于整个应用程序:

UINavigationBar.appearance().backgroundColor = UIColor.greenColor()
UIBarButtonItem.appearance().tintColor = UIColor.magentaColor()
//Since iOS 7.0 UITextAttributeTextColor was replaced by NSForegroundColorAttributeName
UINavigationBar.appearance().titleTextAttributes = [UITextAttributeTextColor: UIColor.blueColor()]
UITabBar.appearance().backgroundColor = UIColor.yellowColor();

斯威夫特5.4.2:

UINavigationBar.appearance().backgroundColor = .green // backgorund color with gradient
// or
UINavigationBar.appearance().barTintColor = .green  // solid color
    
UIBarButtonItem.appearance().tintColor = .magenta
UINavigationBar.appearance().titleTextAttributes = [NSAttributedString.Key.foregroundColor : UIColor.blue]
UITabBar.appearance().barTintColor = .yellow

更多关于UIAppearance API在Swift你可以阅读这里。

iOS 8 (swift)

let font: UIFont = UIFont(name: "fontName", size: 17)   
let color = UIColor.backColor()
self.navigationController?.navigationBar.topItem?.backBarButtonItem?.setTitleTextAttributes([NSFontAttributeName: font,NSForegroundColorAttributeName: color], forState: .Normal)

斯威夫特3

你可以在ViewDidLoad()中使用简单的一行代码

//Change Color
    self.navigationController?.navigationBar.barTintColor = UIColor.red
//Change Text Color
    self.navigationController?.navigationBar.titleTextAttributes = [NSForegroundColorAttributeName: UIColor.white]

Swift 4, iOS 12和Xcode 10更新

只需在viewDidLoad()中放入一行

navigationController?.navigationBar.barTintColor = UIColor.red