react-amap中获取map实例运用map.setFitVi

在使用react-amap框架，加载地图使用的方法是引入<Map />，在构造Map时，加入<Map evente属性：events={{ created: (el) => { this.mapEl = el; }, }} >
代码示例：

import { Map, Marker, } from 'react-amap' ;
export default Network extends PureComponent { 
  loadUI() {
    window.AMapUI.loadUI(['geo/DistrictExplorer'], (DistrictExplorer) => {
      const _this = this;
        // 1.创建一个实例
      var districtExplorer = new DistrictExplorer({
        eventSupport: true,
            map: _this.mapEl
      });
      districtExplorer.loadMultiAreaNodes(adcodes, function(error, areaNodes) {
            //注意节点的顺序，前面的高优先级
            districtExplorer.setAreaNodesForLocating(areaNodes);
            //清除已有的绘制内容
            districtExplorer.clearFeaturePolygons();
            for (var i = 0, len = areaNodes.length; i < len; i++) {
                _this.renderAreaNode(districtExplorer, areaNodes[i]);
            }
            //更新地图视野
            _this.mapEl.setFitView(districtExplorer.getAllFeaturePolygons());
      });
    })
  }

  render(){
    <Map
         amapkey={mapKey}
         mapStyle='amap://styles/light'
         center={this.state.position}
         events={{
           created: (el) => {
             this.mapEl = el;
             this.loadUI();
           },
        }}
    />
  }
)