An example how to use ContextMenu add-on together with V-Leaflet

MyUI.java

package org.bluemix.challenge;

import javax.servlet.annotation.WebServlet;

import com.vaadin.annotations.Theme;
import com.vaadin.annotations.VaadinServletConfiguration;
import com.vaadin.annotations.Widgetset;
import com.vaadin.server.Page;
import com.vaadin.server.VaadinRequest;
import com.vaadin.server.VaadinServlet;
import com.vaadin.ui.Button;
import com.vaadin.ui.Button.ClickEvent;
import com.vaadin.ui.Label;
import com.vaadin.ui.Notification;
import com.vaadin.ui.UI;
import com.vaadin.ui.VerticalLayout;
import org.vaadin.addon.leaflet.LMap;
import org.vaadin.addon.leaflet.LMarker;
import org.vaadin.addon.leaflet.LOpenStreetMapLayer;
import org.vaadin.addon.leaflet.LeafletContextMenuEvent;
import org.vaadin.addon.leaflet.LeafletContextMenuListener;
import org.vaadin.addon.leaflet.shared.Point;
import org.vaadin.peter.contextmenu.ContextMenu;
import org.vaadin.peter.contextmenu.ContextMenu.ContextMenuItem;

/**
 *
 */
@Theme("mytheme")
@Widgetset("org.bluemix.challenge.MyAppWidgetset")
public class MyUI extends UI {

    @Override
    protected void init(VaadinRequest vaadinRequest) {
        final VerticalLayout layout = new VerticalLayout();
        layout.setMargin(true);
        setContent(layout);

        Button button = new Button("Click Me");
        button.addClickListener(new Button.ClickListener() {
            @Override
            public void buttonClick(ClickEvent event) {
                int clientX = event.getClientX();
                layout.addComponent(new Label("Thank you for clicking"));
            }
        });
        layout.addComponent(button);

        layout.addComponent(new Label("Foobar"));

        Page.getCurrent().getStyles().add(
                ".leaflet-container {cursor :crosshair !important;}");

        final LMap leafletMap = new LMap();

        leafletMap.setZoomLevel(1);
        leafletMap.setCenter(0, 0);
        leafletMap.addLayer(new LOpenStreetMapLayer());

        final ContextMenu contextMenu = new ContextMenu();

        final ContextMenuItem addMarker = contextMenu.addItem("Try me").addItem(
                "Add marker");
        final ContextMenu.ContextMenuItem addCircle = contextMenu.
                addItem("Add circle");
        final ContextMenuItem addPath = contextMenu.
                addItem("Add start new path");
        final ContextMenuItem startPolygon = contextMenu.addItem(
                "Add start new polygon");

        contextMenu.setAsContextMenuOf(leafletMap);
        contextMenu.setOpenAutomatically(false);

        final Point p = new Point();

        final ContextMenu.ContextMenuItemClickListener contextMenuItemClickListener = new ContextMenu.ContextMenuItemClickListener() {

            @Override
            public void contextMenuItemClicked(
                    ContextMenu.ContextMenuItemClickEvent ctxEvent) {
                ContextMenuItem source = (ContextMenuItem) ctxEvent.
                        getSource();

                if (source == addMarker) {
                    LMarker marker = new LMarker(p);
                    marker.setPopup("Created by context click on LMap");
                    leafletMap.addComponent(marker);
                } else {
                    Notification.show(
                            "Try adding marker, this was just an ad ;-)");
                }
            }
        };

        contextMenu.addItemClickListener(contextMenuItemClickListener);

        leafletMap.addContextMenuListener(new LeafletContextMenuListener() {
            @Override
            public void onContextMenu(final LeafletContextMenuEvent event) {

                Point point = event.getPoint();
                p.setLat(point.getLat());
                p.setLon(point.getLon());

                contextMenu.open((int) event.getClientX(), (int) event.
                        getClientY());
            }
        });
        leafletMap.setHeight("300px");
        leafletMap.setWidth("300px");
        layout.addComponent(leafletMap);

    }

    @WebServlet(urlPatterns = "/*", name = "MyUIServlet", asyncSupported = true)
    @VaadinServletConfiguration(ui = MyUI.class, productionMode = false)
    public static class MyUIServlet extends VaadinServlet {
    }
}

Sorry, it is actually v-leaflet-shramov that gives the google map layer.