ActivityMapper activityMapper = new NetmusActivityMapper(clientFactory);
ActivityManager activityManager = new ActivityManager(activityMapper, eventBus);
activityManager.setDisplay(app_widget);
// Start PlaceHistoryHandler with our PlaceHistoryMapper
NetmusPlaceHistoryMapper historyMapper= GWT.create(NetmusPlaceHistoryMapper.class);
PlaceHistoryHandler historyHandler = new PlaceHistoryHandler(historyMapper);
historyHandler.register(placeController, eventBus, default_place);
RootPanel.get().setStyleName( "gwt-root" );
// applet e' la barra applet, resta inizialmente invisibile e vuota