protected void drawInfoWindow(LatLng position, double elevation) {
   HTML html = new HTML("Elevation is " + elevation + " at " + position.getToString());
   InfoWindowOptions options = InfoWindowOptions.newInstance();
   options.setContent(html);
   InfoWindow iw = InfoWindow.newInstance(options);
   iw.setPosition(position);
   iw.open(mapWidget);
 }