     fileprivate func slideDownAnimationWithOpen() {
         var itemHeight: CGFloat = 0
         for item in items {
-            if item.hidden == true { continue }
+            if item.isHidden == true { continue }
             itemHeight += item.size + itemSpace
-            UIView.animateWithDuration(0.2, delay: 0, options: [], animations: { () -> Void in
+            UIView.animate(withDuration: 0.2, delay: 0, options: [], animations: { () -> Void in
                                         item.frame.origin.y = itemHeight
                                         item.frame.origin.x = 4
                                         item.alpha = 1

                slideDownAnimationWithClose()
            case .none:
                noneAnimationWithClose()
            case default:
                noneAnimationWithClose()
            }
        }

    }

    fileprivate func slideDownAnimationWithClose() {
        for item in items.reversed() {
            if item.isHidden == true { continue }
            UIView.animate(withDuration: 0.2, delay: 0, options: [], animations: { () -> Void in
                item.frame.origin.y = 0
                item.alpha = 0
                }, completion: nil)
