How to set background image for UINavigationBar on different iOS Devices

Question

I want to set full image on UINavigationBar, for this I have:

@2x image (640 x 128)
@3x image (960 x 192)

Below Screenshot is the

Answer 1

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

2.The height of navigation bar is changed from 44 points (88 pixels) to 64 points (128 pixels).