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。

在Swift 2中

在导航栏中更改颜色，

navigationController?.navigationBar.barTintColor = UIColor.whiteColor()

在项目导航栏中更改颜色，

navigationController?.navigationBar.tintColor = UIColor.blueColor()

or

navigationController!.navigationBar.titleTextAttributes = [NSForegroundColorAttributeName: UIColor.blueColor()]

Swift 5，一个简单的UINavigationController扩展方法。在这个答案的底部是扩展和预览。

第一个视图控制器(Home):

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    navigationController?.setTintColor(.white)
    navigationController?.backgroundColor(.orange)
}

第二个视图控制器(详细信息):

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    navigationController?.transparentNavigationBar()
    navigationController?.setTintColor(.black)
}

UINavigationController的扩展:

extension UINavigationController {
    func transparentNavigationBar() {
        self.navigationBar.setBackgroundImage(UIImage(), for: .default)
        self.navigationBar.shadowImage = UIImage()
        self.navigationBar.isTranslucent = true
    }

    func setTintColor(_ color: UIColor) {
        self.navigationBar.titleTextAttributes = [NSAttributedString.Key.foregroundColor: color]
        self.navigationBar.tintColor = color
    }

    func backgroundColor(_ color: UIColor) {
        navigationBar.setBackgroundImage(nil, for: .default)
        navigationBar.barTintColor = color
        navigationBar.shadowImage = UIImage()
    }
}

故事板视图:

预览:

UINavigationBar.appearance().barTintColor = UIColor(red: 46.0/255.0, green: 14.0/255.0, blue: 74.0/255.0, alpha: 1.0)
UINavigationBar.appearance().tintColor = UIColor.whiteColor()
UINavigationBar.appearance().titleTextAttributes = [NSForegroundColorAttributeName : UIColor.whiteColor()]

只需将这一行粘贴到代码中的didFinishLaunchingWithOptions中。

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
}

iOs 14 +

init() {        
    let appearance = UINavigationBarAppearance()
    appearance.shadowColor = .clear // gets also rid of the bottom border of the navigation bar
    appearance.configureWithTransparentBackground() 
    UINavigationBar.appearance().standardAppearance = appearance
    UINavigationBar.appearance().scrollEdgeAppearance = appearance
}