private void toggleHeatMapVisibility() {
   if (heatMapVisible) {
     heatMapVisible = false;
     mapView.getOverlays().remove(heatMapOverlay);
     mapView.invalidate();
   } else {
     heatMapVisible = true;
     mapView.getOverlays().add(heatMapOverlay);
     mapView.invalidate();
   }
 }
 @Override
 @Subscribe
 public void onEvent(SessionChangeEvent event) {
   super.onEvent(event);
   refreshNotes();
   mapView.invalidate();
 }
 private void refresh() {
   boolean complete = (requestsOutstanding == 0) && soundTraceComplete;
   if (complete) {
     stopSpinner();
   } else {
     startSpinner();
   }
   if (!complete) mapView.invalidate();
 }
  @Subscribe
  public void onEvent(LocationEvent event) {
    updateRoute();

    mapView.invalidate();
  }