Adding blur effect to background in swift

Question

I am setting a background image to view controller. But also i want to add blur effect to this background. How can I do this?

I am setting background with following

Answer 1

In a UIView extension:

func addBlurredBackground(style: UIBlurEffect.Style) {
    let blurEffect = UIBlurEffect(style: style)
    let blurView = UIVisualEffectView(effect: blurEffect)
    blurView.frame = self.frame
    blurView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
    self.addSubview(blurView)
    self.sendSubviewToBack(blurView)
}