JSF级联下拉

Question

我遇到了一种奇怪的行为。我的项目中有级联要求，所以我在我的个人笔记本电脑上做了一个小代码片段，但是同样的事情在我的项目中无法解释下面的场景：

Bean代码：

/**
 * LoginBean.java
 */
package com.tutorial;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import javax.faces.event.AjaxBehaviorEvent;
import javax.faces.model.SelectItem;

public class LoginBean
{
    private String name;
    private String password;
    private String dropDownValue;
    private String dropDownTwoValue;
    Set<SelectItem> testDropDown = new HashSet<SelectItem>();
    Set<SelectItem> testDropDownTwo = new HashSet<SelectItem>();
    Set<SelectItem> hhs = new HashSet<SelectItem>();

    public String getDropDownValue() {
        System.out.println("getttttttttttttttttttt");
        return dropDownValue;
    }


    public void setDropDownValue(String dropDownValue) {
        this.dropDownValue = dropDownValue;
    }


    public String getDropDownTwoValue() {
        return dropDownTwoValue;
    }


    public void setDropDownTwoValue(String dropDownTwoValue) {
        this.dropDownTwoValue = dropDownTwoValue;
    }


    public Set<SelectItem> getTestDropDown() {
        testDropDown.add(new SelectItem("One"));
        testDropDown.add(new SelectItem("Two"));
        testDropDown.add(new SelectItem("Three"));
        testDropDown.add(new SelectItem("Four"));
        return testDropDown;
    }


    public Set<SelectItem> getTestDropDownTwo() {
        return testDropDownTwo;
    }


    public void setTestDropDownTwo(List<SelectItem> testDropDownTwo) {

    }


    public void setTestDropDown(Set<SelectItem> testDropDown) {

        this.testDropDown = testDropDown;
    }

    public String getName ()
    {
        return name;
    }


    public void setName (final String name)
    {
        this.name = name;
    }


    public String getPassword ()
    {
        return password;
    }


    public void setPassword (final String password)
    {
        this.password = password;
    }
    public String submit() {
        // Do your thing here.
        // ...
        System.out.println("****LoginBean***submit***");
        return "login";
    }
    public void changeDropDownOne() {
        System.out.println("^^^"+getDropDownTwoValue()+"^^^^^");
        String dropDownTwoValueTempValue = getDropDownTwoValue();
        String dp = getDropDownValue();
        if(dp != null) {
            System.out.println("kggggggggggggggggggggggggggggggggggggggggetTestDropDownTwo********************************"+dp);
            if(dp.equalsIgnoreCase("One")) {
                testDropDownTwo = new HashSet<SelectItem>();
                if(dropDownTwoValueTempValue!=null && !dropDownTwoValueTempValue.equalsIgnoreCase("****select***")) {
                    testDropDownTwo.add(new SelectItem(dropDownTwoValueTempValue));
                }  else {
                    testDropDownTwo.add(new SelectItem("****select***"));
                }
                testDropDownTwo.add(new SelectItem("One - One"));
                testDropDownTwo.add(new SelectItem("One - Two"));
                testDropDownTwo.add(new SelectItem("One - Three"));
                testDropDownTwo.add(new SelectItem("One - Four"));
            } else if(dp.equalsIgnoreCase("Two")) {
                testDropDownTwo = new HashSet<SelectItem>();
                if(dropDownTwoValueTempValue!=null && !dropDownTwoValueTempValue.equalsIgnoreCase("****select***")) {
                    testDropDownTwo.add(new SelectItem(dropDownTwoValueTempValue));
                }  else {
                    testDropDownTwo.add(new SelectItem("****select***"));
                } 
                testDropDownTwo.add(new SelectItem("Two - One"));
                testDropDownTwo.add(new SelectItem("Two - Two"));
                testDropDownTwo.add(new SelectItem("Two - Three"));
                testDropDownTwo.add(new SelectItem("Two - Four"));
            }else if(dp.equalsIgnoreCase("Three")) {
                testDropDownTwo = new HashSet<SelectItem>();
                if(dropDownTwoValueTempValue!=null && !dropDownTwoValueTempValue.equalsIgnoreCase("****select***")) {
                    testDropDownTwo.add(new SelectItem(dropDownTwoValueTempValue));
                }  else {
                    testDropDownTwo.add(new SelectItem("****select***"));
                } 
                testDropDownTwo.add(new SelectItem("Three - One"));
                testDropDownTwo.add(new SelectItem("Three - Two"));
                testDropDownTwo.add(new SelectItem("Three - Three"));
                testDropDownTwo.add(new SelectItem("Three - Four"));
            }else {
                testDropDownTwo = new HashSet<SelectItem>();
                if(dropDownTwoValueTempValue!=null && !dropDownTwoValueTempValue.equalsIgnoreCase("****select***")) {
                    testDropDownTwo.add(new SelectItem(dropDownTwoValueTempValue));
                }  else {
                    testDropDownTwo.add(new SelectItem("****select***"));
                } 
                testDropDownTwo.add(new SelectItem("Four - One"));
                testDropDownTwo.add(new SelectItem("Four - Two"));
                testDropDownTwo.add(new SelectItem("Four - Three"));
                testDropDownTwo.add(new SelectItem("Four - Four"));
            }
        }
        //return testDropDownTwo;
    }
}

XHTML代码：

<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:h="http://java.sun.com/jsf/html">

<h:head>

<h:outputScript name="jsf.js" library="javax.faces"/>

</h:head>

<body>

<h:form>

<h:selectOneMenu id="dropDownValue" value="#{loginBean.dropDownValue}" >
                            <f:selectItem itemValue="****select***" />
                            <f:selectItems value="#{loginBean.testDropDown}"/>
                            <f:ajax render="testDropDownTwo"  listener="#{loginBean.changeDropDownOne}" /> 
                        </h:selectOneMenu>

 <h:selectOneMenu id="testDropDownTwo" value="#{loginBean.dropDownTwoValue}" >
                            <f:selectItem itemValue="****select***" />
                            <f:selectItems value="#{loginBean.testDropDownTwo}" />
                        </h:selectOneMenu>

</h:form>

</body>

</html>

在我的办公室系统中，当我更改第一个下拉菜单时，控件将更改为DropDownOne并且testDropDownTwo正在更新，但该值不会反映第二个下拉列表。

请帮助我完成他的regrard

由于

KK