         v.contentMode = .scaleAspectFit
         v.isUserInteractionEnabled = true
         v.addGestureRecognizer(panGesture)
+        v.addGestureRecognizer(doubleTapGesture)
         return v
     }()
     
     private lazy var panGesture = UIPanGestureRecognizer(target: self, action: #selector(handleGesture(_:)))
+    private lazy var doubleTapGesture: UITapGestureRecognizer = {
+        let g = UITapGestureRecognizer(target: self, action: #selector(handleDoubleTapGesture(_:)))
+        g.numberOfTapsRequired = 2
+        return g
+    }()
     
     private lazy var blurredView: UIVisualEffectView = {
         let v = UIVisualEffectView(effect: UIBlurEffect(style: .dark))


//MARK: Helper
extension ImageViewerViewController {
    func aspectFitRect(forSize size: CGSize, insideRect: CGRect) -> CGRect {
        return AVMakeRect(aspectRatio: size, insideRect: insideRect)
    }

    private var animator: ImageViewerAnimator?
    //    private var isZooming = false
    //    var shouldDismiss = false
    
    /// Create imageViewer with transition animation from view/imageview/cell...
    ///
