set navigationBar background image in swift

Question

Code below is not working for me, can anyone help to figure it out what is wrong?

var image = UIImage(named: "10384605_10152519403846670_5189785375955620548_n.jpg") as UIImage

self.navigationController.navigationBar.setBackgroundImage(image , forBarMetrics:UIBarMetrics)

Answer 1

self.navigationController.navigationBar.setBackgroundImage(image, 
                                                   forBarMetrics: .Default)

Answer 2

In AppDelegate.swift

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

    //Image Background Navigation Bar
    let navBackgroundImage:UIImage! = UIImage(named: "backgroundNB.png")
    UINavigationBar.appearance().setBackgroundImage(navBackgroundImage, forBarMetrics: .Default)

    return true
}

Answer 3

In Swift 3:

If you want to add a repeating image in the background you can make this call in AppDelegate > didFinishLaunchingWithOptions:

let image = UIImage(named: "imageNameInAsset")
UINavigationBar.appearance().setBackgroundImage(image, for: .default)

If you want to add an image to the center of the navigation bar you need to do this in the ViewController > viewWillAppear:

let titleView = UIImageView(image: UIImage(named: "imageNameInAsset"))
self.navigationItem.titleView = titleView