网页中添加三层菜单

gf 的项目中需要用到三层菜单，总结如下：

Renders a Javascript Menu based on the excellent JSCookMenu by Heng Yuan(http://www.cs.ucla.edu/~heng/JSCookMenu), the nested NavigationMenuItem(s) are rendered as Javascript Menu.

If you want to use jscookMenu in your application, you will have to:
* Add jscookmenu directory containing css and scripting code to your web directory (you can find it in the examples application).
* Add scripts and stylesheets for the theme you would like to use to html-header (see also inc/header.inc in the examples application)
* Put the tomahawk.jar in your WEB-INF/lib directory (or in the classpath of your application server.)
* Add the following to your JSP page in order to use one of the MyFaces custom components:
<%@ taglib uri="http://myfaces.apache.org/tomahawk" prefix="t" %>

Well,the syntax of jscookMenu is as follows:

<t:jscookMenu [ user-role-support-attributes ]
                 [layout="values {hbr, hbl, hur, hul, vbr, vbl, vur, vul}"]
                 [theme="values {ThemeIE, ThemeMiniBlack, ThemeOffice, ThemePanel}"]
    Nested <t:navigationMenuItem> or <t:navigationMenuItems> tags (menu items)
</t:jscookMenu>

不同的 theme (效果)可以到这里查看 http://jscook.yuanheng.org/JSCookMenu/ThemeMiniBlack.html

例子：
The code in my menu.jsp is as follows:

<%@ taglib uri="http://myfaces.apache.org/extensions" prefix="x"%>
<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h"%>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f"%>
 
<x:jscookMenu layout="vbr" theme="ThemeECCGroup" rendered="#{MenuBean.hasMenu}">
  <x:navigationMenuItems value="#{MenuBean.menu}" />
</x:jscookMenu>


The code in my backing bean is as follows: (this will eventually be generated from the database)

/**
* Package that this class belongs to.
*/
package uk.co.eccgroup.controller.action;
 
import java.util.ArrayList;
import java.util.List;
 
import javax.faces.context.FacesContext;
 
import org.apache.myfaces.custom.navmenu.NavigationMenuItem;
import org.apache.log4j.Logger;
 
/**
 * MenuBean backing bean for application menus
 */
public class MenuBean
{
  private static final Logger logger = Logger.getLogger(MenuBean.class);
 
  public List<NavigationMenuItem> getContextMenu()
 {
   //Get view id
  String viewId = FacesContext.getCurrentInstance().getViewRoot().getViewId();
  logger.debug("view id: " + viewId);
       
  //Menu
  List<NavigationMenuItem> contextMenu = null;
  
  if(viewId.equals("/home.jsp"))
  {
   //Context Menu
   contextMenu = new ArrayList<NavigationMenuItem>();
   contextMenu.add(new NavigationMenuItem("Application Development", "nav_services_applicationdevelopment", null, false));
   contextMenu.add(new NavigationMenuItem("Consultancy Services", "nav_services_consultancy", null, false));
   contextMenu.add(new NavigationMenuItem("Recruitment Services", "nav_services_recruitment", null, false));
   contextMenu.add(new NavigationMenuItem("Contact Us", "nav_contact", null, false));
  }
  
  if(
      viewId.equals("/applicationdevelopment.jsp")
    || viewId.equals("/recruitment.jsp")
   )
  {
   contextMenu = new ArrayList<NavigationMenuItem>();
   contextMenu.add(new NavigationMenuItem("Price Guide", "nav_price", null, false));
   contextMenu.add(new NavigationMenuItem("Contact Us", "nav_contact", null, false));
  }
  
  if(viewId.equals("/consultancy.jsp"))
  {
   contextMenu = new ArrayList<NavigationMenuItem>();
   contextMenu.add(new NavigationMenuItem("Our Consultants", "nav_consultants", null, false));
   contextMenu.add(new NavigationMenuItem("Price Guide", "nav_price", null, false));
   contextMenu.add(new NavigationMenuItem("Contact Us", "nav_contact", null, false));
  }
  
  //Return menu
  return contextMenu;
 }
 
 public boolean getHasContextMenu()
 {
   boolean hasMenu = false;
  
  List<NavigationMenuItem> contextMenu = getContextMenu();
  
  if(contextMenu != null)
   hasMenu = true;
   
  return hasMenu;
 }
 
 public boolean getHasMenu()
 {
   return true;
 }
 
 public List<NavigationMenuItem> getMenu()
  {
   //Main Menu
  List<NavigationMenuItem> menu = new ArrayList<NavigationMenuItem>();
  menu.add(new NavigationMenuItem("Home", "nav_home", null, false));
  menu.add(new NavigationMenuItem("Our Consultants", "nav_consultants", null, false));
  menu.add(new NavigationMenuItem("Services", "nav_services", null, false));
  //menu.add(new NavigationMenuItem("Documents", "nav_documents", null, false));
  menu.add(new NavigationMenuItem("Price Guide", "nav_price", null, false));
  //menu.add(new NavigationMenuItem("Web Log", "nav_weblog", null, false));
  menu.add(new NavigationMenuItem("Contact Us", "nav_contact", null, false));
  
  //Services Sub Menu
  List<NavigationMenuItem> services = new ArrayList<NavigationMenuItem>();
  services.add(new NavigationMenuItem("Application Development", "nav_services_applicationdevelopment", null, false));
  services.add(new NavigationMenuItem("Consultancy", "nav_services_consultancy", null, false));
  services.add(new NavigationMenuItem("Recruitment Services", "nav_services_recruitment", null, false));
  
  //Documents Sub Menu
  List<NavigationMenuItem> documents = new ArrayList<NavigationMenuItem>();
   documents.add(new NavigationMenuItem("AJAX", "nav_documents_ajax", null, false));
   documents.add(new NavigationMenuItem("EJB", "nav_documents_ejb", null, false));
   documents.add(new NavigationMenuItem("Hibernate", "nav_documents_hibernate", null, false));
   documents.add(new NavigationMenuItem("JBoss", "nav_documents_jboss", null, false));
   documents.add(new NavigationMenuItem("JSF", "nav_documents_jsf", null, false));
    
  //Add services to main menu
  NavigationMenuItem[] servicesArray = services.toArray(new NavigationMenuItem[0]);
  menu.get(2).setNavigationMenuItems(servicesArray);
  
  //Add documents to main menu
  NavigationMenuItem[] documentsArray = documents.toArray(new NavigationMenuItem[0]);
  //menu.get(3).setNavigationMenuItems(documentsArray);
  
  //Return menu
  return menu;
  }
 
  public void setContextMenu(List<NavigationMenuItem> contextMenu)
 {
  //Do nothing
 }
 
 public void setHasContextMenu(boolean hasContextMenu)
  {
   //Do nothing
  }
 
 public void setHasMenu(boolean hasMenu)
  {
   //Do nothing
  }
 
  public void setMenu(List<NavigationMenuItem> menu)
 {
  //Do nothing
 }
}