     }
     
     // MARK: Layout
-    
     private func updateProperties() {
         // using init() will raise CGPostError, lets prevent it
-        if bounds == CGRectZero { return }
+        if bounds == CGRect.zero { return }
         
         createLayersIfNeeded()
         if onOffLayer != nil {
             onOffLayer.lineWidth   = lineWidth
-            onOffLayer.strokeColor = strokeColor.CGColor
+            onOffLayer.strokeColor = strokeColor.cgColor
         }
         
         if ringLayer != nil {

    }
    
    private func ringColorWithAlpha() -> CGColor {
        return strokeColor.colorWithAlphaComponent(ringAlpha).CGColor
    }
    
    // MARK: Animations

                strokeStart    = animations.strokeStart
                strokeEnd      = animations.strokeEnd
            }
            onOffLayer.applyAnimation(animation: strokeStart)
            onOffLayer.applyAnimation(animation: strokeEnd)
        }
    }
    
