uinavigationbar - set navigationBar background image in swift -

uinavigationbar - set navigationBar background image in swift -

code below not working me, can help figure out wrong?

var image = uiimage(named: "10384605_10152519403846670_5189785375955620548_n.jpg") uiimage self.navigationcontroller.navigationbar.setbackgroundimage(image , forbarmetrics:uibarmetrics)

self.navigationcontroller.navigationbar.setbackgroundimage(image, forbarmetrics: .default)

uinavigationbar swift ios8