public void clear() {
   if (aMap != null) {
     aMap.clear();
     markerMgr.clearAll();
     overlayMgr.clearAll();
   }
 }
 /** 方法必须重写 */
 @Override
 protected void onDestroy() {
   if (aMap != null) {
     aMap.clear();
   }
   overlayMgr.clean();
   markerMgr.clearAll();
   stopLocation();
   super.onDestroy();
   mapView.onDestroy();
 }
 public void addGroundOverlay(GroundBean bean) {
   overlayMgr.addGround(bean);
 }
 public void addPolygonOverlay(PolygonBean bean) {
   overlayMgr.addPolygon(bean);
 }
 public void addCircleOverlay(CircleBean bean) {
   overlayMgr.addCircle(bean);
 }
 public void addArcOverlay(ArcBean bean) {
   overlayMgr.addArc(bean);
 }
 public void removeOverlay(String id) {
   overlayMgr.removeOverlay(id);
 }
 public void addPolylineOverlay(PolylineBean bean) {
   overlayMgr.addPolylines(bean);
 }