实例：Easyui的combobox实现动态数据级联

实现从数据库中动态获取对应的List集合，并在Easyui的combobox中显示出来。

实现的效果如下：







1、数据库的表设计如图所示



2、数据库中填写相关的数据，如图所示。如图所示【法律法规】是所属栏目，因此他的字段parentid是0。【中国公民出国】、【内地居民往来港澳】是属于法律法规的类别。因此他们的字段parentid是对应1，【法律法规】的字段categoryid是1.



3、相关的配置：已经在前面的博客中写了http://blog.csdn.net/lhq13400526230/article/details/9158111

这里就不多写。只把关键代码贴出来。

4、对应的Action代码

[java] view
plaincopy

package crj.portal.web.management.action;

import java.io.IOException;

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import net.sf.json.JSONArray;

import net.sf.json.JSONObject;

import net.sf.json.JsonConfig;

import org.apache.log4j.Logger;

import org.apache.struts2.ServletActionContext;

import org.hibernate.Criteria;

import org.hibernate.criterion.Order;

import com.sun.tools.javac.util.Log;

import crj.portal.web.management.model.Cpersontypetbl;

import crj.portal.web.management.service.CategoryService;

import crj.portal.web.management.service.ItemService;

import crj.portal.web.management.service.UserService;

public class ItemManageAction {

Logger log=Logger.getLogger(this.getClass());

private String page;

private String rows;

private String lanmuid;

private ItemService itemService;// 依赖注入

//下拉框--查询栏目

public String categorytbl() throws Exception{

List list=itemService.queryLanMu();

this.toJsonArray(list);

return null;

}

//根据栏目的ID 查询拥有的类别

public String leibie() throws Exception{

List list=itemService.queryLeiBie(lanmuid);

this.toJsonArray(list);

return null;

}

public String toJsonArray(List list) throws IOException{

HttpServletResponse response = ServletActionContext.getResponse();

HttpServletRequest request = ServletActionContext.getRequest();

JSONArray json = JSONArray.fromObject(list);

log.info("JSON格式：" +json.toString());

response.setCharacterEncoding("utf-8");// 指定为utf-8

response.getWriter().write(json.toString());// 转化为JSOn格式

return null;

}

public String save() throws Exception {

return this.alllist();

}

public ItemService getItemService() {

return itemService;

}

public void setItemService(ItemService itemService) {

this.itemService = itemService;

}

public String getPage() {

return page;

}

public void setPage(String page) {

this.page = page;

}

public String getRows() {

return rows;

}

public void setRows(String rows) {

this.rows = rows;

}

public UserService getUserService() {

return userService;

}

public void setUserService(UserService userService) {

this.userService = userService;

}

public CategoryService getCategoryService() {

return categoryService;

}

public void setCategoryService(CategoryService categoryService) {

this.categoryService = categoryService;

}

public String getLanmuid() {

return lanmuid;

}

public void setLanmuid(String lanmuid) {

this.lanmuid = lanmuid;

}

}

5、对应的接口代码

[java] view
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public interface ItemService {

//下拉框--查询栏目

public List queryLanMu() throws Exception;

//下拉框--查询类别

public List queryLeiBie(String ids) throws Exception;

}

6、对应的接口实现类代码

[java] view
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public class ItemServiceImpl implements ItemService {

Logger log = Logger.getLogger(this.getClass());

private SessionFactory sessionFactory;

//下拉框--查询栏目

public List queryLanMu() throws Exception {

Criteria criteria=this.sessionFactory.getCurrentSession().createCriteria(Categorytbl.class);

criteria.add(Restrictions.eq("parentid", 0));

criteria.addOrder(Order.asc("categoryid"));

return criteria.list();

}

//下拉框--查询类别

public List queryLeiBie(String ids) throws Exception {

int i=Integer.parseInt(ids);

Criteria criteria=this.sessionFactory.getCurrentSession().createCriteria(Categorytbl.class);

criteria.add(Restrictions.eq("parentid", i));

criteria.addOrder(Order.asc("categoryid"));

return criteria.list();

}

public SessionFactory getSessionFactory() {

return sessionFactory;

}

public void setSessionFactory(SessionFactory sessionFactory) {

this.sessionFactory = sessionFactory;

}

}

7、对应的JSP代码

[html] view
plaincopy

<%@ page language="java" errorPage="/error.jsp" pageEncoding="utf-8"%>

<%@ taglib prefix="s" uri="/struts-tags"%>

<%

String path = request.getContextPath();

%>

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>信息管理</title>

<!-- 引入Jquery -->

<script type="text/javascript" src="<%=path%>/easyui_1.3.2/jquery-1.8.0.min.js" charset="utf-8"></script>

<!-- 引入Jquery_easyui -->

<script type="text/javascript" src="<%=path%>/easyui_1.3.2/jquery.easyui.min.js" charset="utf-8"></script>

<!-- 引入easyUi国际化--中文 -->

<script type="text/javascript" src="<%=path%>/easyui_1.3.2/locale/easyui-lang-zh_CN.js" charset="utf-8"></script>

<!-- 引入easyUi默认的CSS格式--蓝色 -->

<link rel="stylesheet" type="text/css" href="<%=path%>/easyui_1.3.2/themes/default/easyui.css" />

<!-- 引入easyUi小图标 -->

<link rel="stylesheet" type="text/css" href="<%=path%>/easyui_1.3.2/themes/icon.css" />

<script type="text/javascript">

/* 初始化下载表格信息 */

$(function() {

// 下拉框选择控件，下拉框的内容是动态查询数据库信息

$('#lanmu').combobox({

url:'itemManage!categorytbl',

editable:false, //不可编辑状态

cache: false,

panelHeight: 'auto',//自动高度适合

valueField:'categoryid',

textField:'categoryName',

onHidePanel: function(){

$("#leibie").combobox("setValue",'');

var lanmuid = $('#lanmu').combobox('getValue');

$.ajax({

type: "POST",

url: "itemManage!leibie?lanmuid="+lanmuid,

cache: false,

dataType : "json",

success: function(data){

$("#leibie").combobox("loadData",data);

}

});

}

});

$('#leibie').combobox({

//url:'itemManage!categorytbl',

editable:false, //不可编辑状态

cache: false,

panelHeight: 'auto',//自动高度适合

valueField:'categoryid',

textField:'categoryName'

});

});

</script>

</head>

<body>

<!-- 工具拦 -->

<div id="tb" style="padding: 3px">

<form >

<span>所属栏目:</span>

<select id="lanmu" class="lanmu" style="width:160px; border: 1px solid #ccc"> </select>

<span>类别:</span>

<select id="leibie" class="leibie" style="width:160px; border: 1px solid #ccc"> </select>

</form>

</div>

</body>

</html>