                 self.isAnimating = false
         })
         
+        let shadowAnim = CABasicAnimation(keyPath: "shadowPath")
+        shadowAnim.duration = 0.3
+        shadowAnim.fromValue = thumbView.layer.shadowPath
+        shadowAnim.toValue = UIBezierPath(roundedRect: thumbView.bounds, cornerRadius: thumbView.layer.cornerRadius).cgPath
+        thumbView.layer.add(shadowAnim, forKey: "shadowPath")
+        thumbView.layer.shadowPath = UIBezierPath(roundedRect: thumbView.bounds, cornerRadius: thumbView.layer.cornerRadius).cgPath
+        
         return true
     }
     

            }, completion: { finished in
                self.isAnimating = false
            })
        }
        else {
            if self.isTracking {

            }, completion: { finished in
                self.isAnimating = false
            })
            
            let shadowAnim = CABasicAnimation(keyPath: "shadowPath")
            shadowAnim.duration = 0.3
            shadowAnim.fromValue = thumbView.layer.shadowPath
            shadowAnim.toValue = UIBezierPath(roundedRect: thumbView.bounds, cornerRadius: thumbView.layer.cornerRadius).cgPath
            thumbView.layer.add(shadowAnim, forKey: "shadowPath")
            thumbView.layer.shadowPath = UIBezierPath(roundedRect: thumbView.bounds, cornerRadius: thumbView.layer.cornerRadius).cgPath
        }
        else {
            if (self.isTracking) {
