blurEffectFadeIniOS10.swift

// iOS 10 working way to fade in a blurred view (changing alpha in the container does not work on iOS 10)
let effectView = UIVisualEffectView()
effectView.frame = toast.bounds
effectView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
view.addSubview(effectView) //replace view with whatever view you want to blur

UIView.animate(withDuration: 0.2) {

    let blur = UIBlurEffect(style: .light)
    effectView.effect = blur
}