EDIT

package eu.etaxonomy.vaadin.ui.mainmenu;

import java.util.Comparator;

import java.util.List;

import java.util.Map;

import java.util.stream.Collectors;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.context.ApplicationContext;

import org.vaadin.spring.events.EventBus.UIEventBus;

import org.vaadin.spring.events.annotation.EventBusListenerMethod;

import com.vaadin.navigator.View;

import com.vaadin.spring.annotation.SpringView;

import eu.etaxonomy.vaadin.ui.MainMenu;

import eu.etaxonomy.vaadin.ui.MenuItem;

import eu.etaxonomy.vaadin.ui.UIInitializedEvent;

// MenuBeanDiscovery is not yet working with spring!!!!!

//

// @NormalUIScoped // FIXME this provided a MenuBeanDiscoveryBean as a proxy, which is the equivalent in spring?

// otherwise the following error will be thrown:

//    Error creating bean with name 'testView': Scope 'vaadin-view' is not active for the current thread;

//    consider defining a scoped proxy for this bean if you intend to refer to it from a singleton

//###DISABLED:

//@SpringComponent

//@UIScope

public class MenuBeanDiscoveryBean {

	@Autowired

	private ApplicationContext beanManager;

    private UIEventBus uiEventBus;

    @Autowired

    private void setUiEventBus(UIEventBus uiEventBus){

        this.uiEventBus = uiEventBus;

        uiEventBus.subscribe(this);

    }

	private MainMenu mainMenuLookup = null;

    MenuBeanDiscoveryBean menuBeanDiscoveryBean;

	public MenuBeanDiscoveryBean() {

	    System.out.println("###########");

	}

	@Autowired

	public void setMainMenu(MainMenu mainMenu){

	    this.mainMenuLookup = mainMenu;

	}

	@EventBusListenerMethod

	protected void doMenuItemLookup(UIInitializedEvent event) {

		if (mainMenuLookup == null) {

		    // IGNORE

			return;

		}

		MainMenu mainMenu = mainMenuLookup;

		Map<String, View> beans = beanManager.getBeansOfType(View.class);

		List<View> menuItemBeans = beans.values().stream()

				.filter(bean -> bean.getClass().isAnnotationPresent(MenuItem.class)).sorted(new BeanNameComparer())

				.collect(Collectors.toList());

		menuItemBeans.forEach(menuItemBean -> {

			MenuItem menuItemAnnotation = menuItemBean.getClass().getAnnotation(MenuItem.class);

			SpringView viewAnnotation = menuItemBean.getClass().getAnnotation(SpringView.class);

			mainMenu.addMenuItem(menuItemAnnotation.name(), menuItemAnnotation.icon(), viewAnnotation.name());

		});

	}

	private static class BeanNameComparer implements Comparator<View> {

		@Override

		public int compare(View a, View b) {

			MenuItem aAnnotation = a.getClass().getAnnotation(MenuItem.class);

			MenuItem bAnnotation = b.getClass().getAnnotation(MenuItem.class);

			return aAnnotation.order() - bAnnotation.order();

		}

	}

}