         cacheImage = nil
         self.drawingPath.removeAllPoints()
         self .setNeedsDisplay()
+        indicatorLabel.hidden = false
     }
     
     func saveAction(){

    //Keep track the four points of bezierPath segment
    private var points = [CGPoint](count: 4, repeatedValue: CGPointZero)
    private var currentTrackIndex = 0
    private lazy var clearButton : UIButton = {
        let button:UIButton = UIButton()
        button.setTitle("重签", forState:.Normal)

        saveButton.snp_makeConstraints { (make) -> Void in
            make.right.bottom.equalTo(self)
            make.size.equalTo(clearButton)
        }
        
        self.addSubview(indicatorLabel)
        indicatorLabel.snp_makeConstraints { (make) -> Void in
            make.center.equalTo(self)
        }
    }
    
