code: public void onFeatureSelected(FeatureSelectedEvent event) {
  		Feature feature = event.getFeature();
  		mapWidget.setController(previousController);
  		previousController = null;
  		service.start(GeometryConverter.toDto(feature.getGeometry()));
  
  		// Now let the user know:
  		if (label != null) {
  			label.destroy();
  			label = null;
  		}
  
  		label = new Label("<p><b>You have selected " + feature.getLabel() + "!</b></p><p>Now continue by drawing a "
  				+ "splitting line on the map. This is done by clicking points on the map, ending with a double " +
  				"click.</p><p>Finally choose an option in the toolbar (finish, cancel, undo, ...).</p>");
  		label.setParentElement(mapWidget);
  		label.setShowEdges(true);
  		label.setBackgroundColor("#ffffd0");
  		label.setPadding(5);
  		label.setWidth(350);
  		label.setTop(25);
  		label.setLeft(-220); // start off screen
  		label.setValign(VerticalAlignment.CENTER);
  		label.setAlign(Alignment.CENTER);
  		label.setAnimateTime(1000); // milliseconds
  		label.addClickHandler(new ClickHandler() {
  
  			public void onClick(ClickEvent event) {
  				label.destroy();
  			}
  		});
  
  		label.animateMove(75, 25);
  	}
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