vaadin and guava eventBus example

VaadinEventBusApplication.java

/*
 * Copyright 2009 IT Mill Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package your.company;

import com.google.common.base.Function;
import com.google.common.eventbus.EventBus;
import com.google.common.eventbus.Subscribe;
import com.vaadin.Application;
import com.vaadin.ui.Button;
import com.vaadin.ui.Label;
import com.vaadin.ui.Window;

/**
 * The Application's "main" class
 */
@SuppressWarnings("serial")
public class VaadinEventBusApplication extends Application {

    private EventBus eventBus = new EventBus();
    private Label label = new Label();

    public class MyEvent {}

    public VaadinEventBusApplication() {
        eventBus.register(new Function<MyEvent, Void>() {
            @Subscribe public Void apply(MyEvent event) {
                label.setValue("text from eventBus");
                return null;
            }
        });
    }

    private Window window;

    @Override
    public void init() {
        window = new Window("My Vaadin Application");
        setMainWindow(window);
        Button button = new Button("Click Me");
        button.addListener(new Button.ClickListener() {
            public void buttonClick(Button.ClickEvent event) {
                eventBus.post(new MyEvent());
            }
        });

        window.addComponent(label);
        window.addComponent(button);

    }

}