             
             // 根据chunk的y值，计算value
             value = calcValueByY()
+            if (valueChangeBlock != nil) {
+                valueChangeBlock!(value)
+            }
             print("value:\(value)")
             
             setNeedsDisplay()

    var selectedColor:UIColor = UIColor.black
    var unselectColor:UIColor = UIColor.red
    var direction:ArrowDirection = .ArrowDirectionHorizontal
    
    private var chunkCircleSize:CGFloat = 0
    

            if value < 0 {
                value = 0
            }
            if (valueChangeBlock != nil) {
                valueChangeBlock!(value)
            }
            chunk.center.y = calcYByValue()
        } else if (tapPoint.y >= chunk.center.y + chunkHeight/6) {
            print("+")
            value += 1
            if value > maxValue {
                value = maxValue
            }
            if (valueChangeBlock != nil) {
                valueChangeBlock!(value)
            }
            chunk.center.y = calcYByValue()
        }
