我必须这么做

UINavigationBar.appearance().tintColor = UIColor.whiteColor()
UINavigationBar.appearance().barStyle = .Black
UINavigationBar.appearance().backgroundColor = UIColor.blueColor()

否则背景颜色不会改变

iOS 10 Swift 3.0

如果你不介意使用swift框架，那么我们UINeraida将导航背景更改为UIColor或HexColor或UIImage，并以编程方式更改导航后退按钮文本，更改完整的前景文本颜色。

对于UINavigationBar

    neraida.navigation.background.color.hexColor("54ad00", isTranslucent: false, viewController: self)
    
    //Change navigation title, backbutton colour
    
    neraida.navigation.foreground.color.uiColor(UIColor.white, viewController: self)
    
    //Change navigation back button title programmatically
    
    neraida.navigation.foreground.backButtonTitle("Custom Title", ViewController: self)
    
    //Apply Background Image to the UINavigationBar
    
    neraida.navigation.background.image("background", edge: (0,0,0,0), barMetrics: .default, isTranslucent: false, viewController: self)

appearance()函数并不总是适用于我。所以我更喜欢创建一个NC对象并改变它的属性。

var navBarColor = navigationController!.navigationBar
navBarColor.barTintColor =
    UIColor(red:  255/255.0, green: 0/255.0, blue: 0/255.0, alpha: 100.0/100.0)
navBarColor.titleTextAttributes =
    [NSForegroundColorAttributeName: UIColor.whiteColor()]

此外，如果你想添加一个图像而不仅仅是文本，这也是可行的

var imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 70, height: 70))
imageView.contentMode = .ScaleAspectFit

var image = UIImage(named: "logo")
imageView.image = image
navigationItem.titleView = imageView

更新为Swift 3, 4, 4.2, 5+

// setup navBar.....
UINavigationBar.appearance().barTintColor = .black
UINavigationBar.appearance().tintColor = .white
UINavigationBar.appearance().titleTextAttributes = [NSForegroundColorAttributeName: UIColor.white]
UINavigationBar.appearance().isTranslucent = false

斯威夫特4

UINavigationBar.appearance().barTintColor = .black
UINavigationBar.appearance().tintColor = .white
UINavigationBar.appearance().titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
UINavigationBar.appearance().isTranslucent = false

Swift 4.2, 5+

UINavigationBar.appearance().barTintColor = .black
UINavigationBar.appearance().tintColor = .white
UINavigationBar.appearance().titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.white]
UINavigationBar.appearance().isTranslucent = false

如果你想使用大标题，添加这一行:

UINavigationBar.navigationBar.prefersLargeTitles = true

也可以查看这里:https://github.com/hasnine/iOSUtilitiesSource

在iOS 15中，UIKit扩展了scrollEdgeAppearance的使用，默认情况下它会生成透明的背景，用于所有导航栏。 设置scrollEdgeAppearance如下代码。

if #available(iOS 15, *) {
        let appearance = UINavigationBarAppearance()
        appearance.configureWithOpaqueBackground()
        appearance.backgroundColor = < your tint color >
        navigationController?.navigationBar.standardAppearance = appearance;
        navigationController?.navigationBar.scrollEdgeAppearance = navigationController?.navigationBar.standardAppearance
    } 

使用外观API和barTintColor颜色。

UINavigationBar.appearance().barTintColor = UIColor.greenColor()