         get {
             return self.knobBg?.image
         }
-        set(img){
-            self.knobBg?.image = img?.withRenderingMode(.alwaysTemplate)
+        set {
+            self.knobBg?.image = newValue?.withRenderingMode(.alwaysTemplate)
         }
     }
     

            UIView.animate(withDuration: 0.25
                , delay: 0
                , options: [.curveEaseOut, .beginFromCurrentState]
                , animations:{
                    self.knobPointer?.transform = CGAffineTransform(rotationAngle: pointerAngle)
                }, completion: nil)
            

        get {
            return Float(self.value)
        }
        set {
            self.setValue(CGFloat(newValue), animated:false)
        }
    }
