arcgisandroid之地图图层切换

ArcGISDynamicMapServiceLayer ady1;
ArcGISDynamicMapServiceLayer ady2;

 ady1= new//动态图层
      ArcGISDynamicMapServiceLayer
    ("http://124.128.9.246:6080/arcgis/rest/services/DC/DCdata/MapServer");
     mapView.addLayer(ady1);

switch (View.getId){
        case 0:
          if (ady1!=null){
            ady1.setVisible(true);
          }
          if(ady2!=null){
           ady2.setVisible(false);
         }
          break; 
        case 1:
          if (ady2!=null){
            ady2.setVisible(true);
          }else {
            ady2= new//动态图层
                ArcGISDynamicMapServiceLayer
                ("http://124.128.9.246:6080/arcgis/rest/services/DC/DCdata/MapServer");
            mapView.addLayer(ady2);
          }
          ady1.setVisible(false);
          break;

      }