我正在尝试不同的方法来制作4个依赖的下拉菜单。通过选择第一个填充2和选择第二个popluate 3rd下拉和选择第三个下拉获得第四个下拉项目列表。
在进行研究时，我发现这一点接近我的想法。这是正常的jsp和ajax得到使用。我正在寻找一个基于struts2的例子，这个例子也使用多个页面来获取列表。每个列表都基于不同的jsp页面。http://www.roseindia.net/answers/viewqa/Ajax/15250-DropDown-in-ajax+jsp.html
strtus2 double select工作得很好，但仅限于两次下拉。无论如何我们可以将它扩展到更多或任何教程或帮助非常感谢。
答案 0 :(得分：5)
Struts2-Jquery有助于使此解决方案有效。但谷歌的帮助并不多，教程已经完成了一半。我认为对于那些想要在他们的项目中实施的人来说，这将是有用的。因此在下面分享。我将尝试上传此war文件并在此处分享链接。
Web.xml中
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:javaee="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" id="WebApp_9" version="2.4">
<display-name>Struts2 Application</display-name>
<filter>
<filter-name>struts2</filter-name>
<filter-class>
org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
struts.xml中
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<constant name="struts.enable.DynamicMethodInvocation" value="false" />
<constant name="struts.devMode" value="false" />
<constant name="struts.custom.i18n.resources" value="ApplicationResources" />
<package name="default" extends="json-default" namespace="/">
<action name="jsonsample" class="net.action.JsonSample">
<result type="json" />
</action>
</package>
</struts>
的index.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<%@ taglib prefix="sj" uri="/struts-jquery-tags"%>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<sj:head jqueryui="true" />
<div id="col3">
<div id="col3_content" class="clearfix">
<s:form id="formSelectReload" action="jsonsample" theme="simple"
cssClass="yform">
<fieldset>
<legend>AJAX Form</legend>
<div class="type-text">
<label for="language">Country: </label>
<s:url id="remoteurl" action="jsonsample" namespace="/"/>
<sj:select href="%{remoteurl}" id="country" onChangeTopics="reloadsecondlist" name="country"
list="countryMap" listKey="myKey" listValue="myValue" emptyOption="false"
headerKey="-1" headerValue="Please Select a Country"/>
</div>
<div class="type-text">
<label for="echo">State: </label>
<s:url id="remoteurl" action="jsonsample" namespace="/"/>
<sj:select href="%{remoteurl}" id="stateID" onChangeTopics="reloadThirdlist" formIds="formSelectReload"
reloadTopics="reloadsecondlist" name="state"
list="stateMap" listKey="myKey" listValue="myValue" emptyOption="false"
headerKey="-1" headerValue="Please Select a State"/>
</div>
<div class="type-text">
<label for="echo">City: </label>
<s:url id="remoteurl" action="jsonsample" namespace="/"/>
<sj:select href="%{remoteurl}" id="cityId" formIds="formSelectReload" reloadTopics="reloadThirdlist"
name="echo" list="cityList" emptyOption="false"
headerKey="-1" headerValue="Please Select a City"/>
</div>
</fieldset>
</s:form>
</div>
</div>
JSonSample.java
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.opensymphony.xwork2.ActionSupport;
public class JsonSample extends ActionSupport {
private Map<String,String> countryMap;
private Map<String,String> stateMap;
private List<String> cityList;
private String country;
private String state;
private String city;
public String execute() {
countryMap = new HashMap<String,String>();
countryMap.put("1", "USA");
countryMap.put("2", "India");
stateMap = new HashMap<String,String>();
if(country != null && country.equalsIgnoreCase("1")){
stateMap.put("1", "New York");
stateMap.put("2", "new jersey");
} else if(country != null && country.equalsIgnoreCase("2")){
stateMap.put("1", "Karnataka");
stateMap.put("2", "Andhra Pradesh");
}
cityList = new ArrayList<String>();
if(country != null && country.equalsIgnoreCase("1") && state != null && state.equalsIgnoreCase("1")){
cityList.add("New York City 1");
cityList.add("New York City 2");
} else if(country != null && country.equalsIgnoreCase("1") && state != null && state.equalsIgnoreCase("2")){
cityList.add("New Jersey City 1");
cityList.add("New Jersey City 2");
} else if(country != null && country.equalsIgnoreCase("2") && state != null && state.equalsIgnoreCase("1")){
cityList.add("Karnataka City 1");
cityList.add("Karnataka City 2");
} else if(country != null && country.equalsIgnoreCase("2") && state != null && state.equalsIgnoreCase("2")){
cityList.add("AP City 1");
cityList.add("Ap City 2");
}
return SUCCESS;
}
public String getJSON() {
return execute();
}
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public Map<String, String> getCountryMap() {
return countryMap;
}
public Map<String, String> getStateMap() {
return stateMap;
}
public List<String> getCityList() {
return cityList;
}
public String index() {
return "success";
}
}
使用的Jar文件：
commons-fileupload-1.3.1.jar
commons-io-2.2.jar
commons-lang-2.4.jar
commons-lang3-3.1.jar
commons-logging-1.1.3.jar
commons-logging-api-1.1.jar
freemarker-2.3.19.jar
javassist-3.11.0.GA.jar
ognl-3.0.6.jar
struts2-core-2.3.16.3.jar
struts2-jquery-plugin-3.7.0.jar
struts2-json-plugin-2.3.16.3.jar
xwork-core-2.3.16.3.jar