docs: function (dimName, axisIndex, dataZoomModel, ecModel) {
  
      /**
       * @private
       * @type {string}
       */
      this._dimName = dimName;
  
      /**
       * @private
       */
      this._axisIndex = axisIndex;
  
      /**
       * @private
       * @type {Array.<number>}
       */
      this._valueWindow;
  
      /**
       * @private
       * @type {Array.<number>}
       */
      this._percentWindow;
  
      /**
       * @private
       * @type {Array.<number>}
       */
      this._dataExtent;
  
      /**
       * {minSpan, maxSpan, minValueSpan, maxValueSpan}
       * @private
       * @type {Object}
       */
      this._minMaxSpan;
  
      /**
       * @readOnly
       * @type {module: echarts/model/Global}
       */
      this.ecModel = ecModel;
  
      /**
       * @private
       * @type {module: echarts/component/dataZoom/DataZoomModel}
       */
      this._dataZoomModel = dataZoomModel;
  
      // /**
      //  * @readOnly
      //  * @private
      //  */
      // this.hasSeriesStacked;
  }