[ios] Adding blur effect to background in swift

This Code is Working Fine For me! its for Swift 4.x

let blurEffect = UIBlurEffect(style: .ExtraLight)
let blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.frame = self.view.frame
self.view.insertSubview(blurEffectView, atIndex: 0)