Issue with UIImageView background in rotation - ios

Question

Hello
I'm trying to put an Image as a background for my ViewControllers, guiding myself for other posts I found this way:
I created the following extension:
extension UIView {
func addBackground() {
// screen width and height:
let width = UIScreen.mainScreen().bounds.size.width
let height = UIScreen.mainScreen().bounds.size.height
let imageViewBackground = UIImageView(frame: CGRectMake(0, 0, width, height))
imageViewBackground.image = UIImage(named: "msa_background")
// you can change the content mode:
imageViewBackground.contentMode = UIViewContentMode.ScaleAspectFill
imageViewBackground.clipsToBounds = true
self.addSubview(imageViewBackground)
self.sendSubviewToBack(imageViewBackground)
}
}
I'm calling this extension in every ViewController with the following code:
override func viewDidLoad() {
super.viewDidLoad()
self.view.addBackground()
}
The problem is when I rotated the screen the image in the background don't fill all the space in the ViewController, I have checked any possible solution that I found but I can't find a way to do it.
I really appreciate any help from you

Answer 1

You are adding the image with the current frame of the screen and never changing it. When you rotate the device it will keep the same frame.
Change it to use AutoLayout like this...
extension UIView {
func addBackground(imageName: String, contentMode: UIViewContentMode) {
let imageViewBackground = UIImageView()
imageViewBackground.image = UIImage(named: imageName)
// you can change the content mode:
imageViewBackground.contentMode = contentMode
imageViewBackground.clipsToBounds = true
imageViewBackground.translatesAutoresizingMaskIntoConstraints = false
self.insertSubview(imageViewBackground, atIndex: 0)
self.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("|[imageViewBackground]|",
options: [],
metrics: nil,
views: ["imageViewBackground", imageViewBackground]))
self.addConstraints(NSLayoutConstraint.constraintsWithVisualFormat("V:|[imageViewBackground]|",
options: [],
metrics: nil,
views: ["imageViewBackground": imageViewBackground]))
}
}
The auto layout constraints will then make the image view fit to the view no matter how the orientation of the device or frame of the view changes.