         let frame = CGRect(
             x: TextView.WidthMargin,
             y: -TextView.Height,
-            width: UIScreen.mainScreen().bounds.size.width - 2 * TextView.WidthMargin,
+            width: UIScreen.main.bounds.size.width - 2 * TextView.WidthMargin,
             height: TextView.Height)
         super.init(frame: frame, textContainer: nil)
         layer.cornerRadius = TextView.CornerRadius

private struct TextView {
    static let CornerRadius: CGFloat = 10
    static let WidthMargin: CGFloat = 10
    static let Height = UIScreen.mainScreen().bounds.size.height / 5
}

internal class ButterflyTextView : UITextView {

    func show() {
        if isShowing == false {
            isShowing = true
            UIView.animate(withDuration: 0.5,
                delay: 0,
                usingSpringWithDamping: 0.5,
                initialSpringVelocity: 0.7,
