Home > Article > Web Front-end > JQuery ztree asynchronous loading example explanation_jquery
Originally, I wanted to make a file directory browsing interface, which required traversing all files and directories. Obviously, reading it all at once is very time-consuming and laborious.
So you need to do asynchronous loading....
Preparation:
1 Download JQuery ZTree
Just copy the JS and CSS. In fact, there is no need to include so many, just use whatever you want.
2 requires fastJSON to convert JSON objects
After I downloaded the JAR package and imported it into Eclipse, I always received a class not found error.
Solution: Place the jar package under WEB-INF/lib.
Code example:
index.jsp
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>Insert title here</title> <link rel="stylesheet" href="resources/css/demo.css" type="text/css"> <link rel="stylesheet" href="resources/css/zTreeStyle/zTreeStyle.css" type="text/css"> <script type="text/javascript" src="resources/js/jquery-1.4.4.min.js"></script> <script type="text/javascript" src="resources/js/jquery.ztree.core-3.5.js"></script> </head> <body> <div class="zTreeDemoBackground left"> <ul id="treeDemo" class="ztree"></ul> </div> <SCRIPT type="text/javascript"> var setting = { data: { simpleData: { enable: true } } , async: { enable: true, url:"/TestZTree/test", autoParam:["id", "name", "level"], otherParam:{"otherParam":"zTreeAsyncTest"}, dataFilter: filter } }; function filter(treeId, parentNode, childNodes) { if (!childNodes) return null; for (var i=0, l=childNodes.length; i<l; i++) { childNodes[i].name = childNodes[i].name.replace(/\.n/g, '.'); } return childNodes; } var zNodes =[ { id:1, pId:0, name:"parentNode 1", open:true}, { id:11, pId:1, name:"parentNode 11",isParent:true}, { id:111, pId:11, name:"leafNode 111"}, { id:112, pId:11, name:"leafNode 112"}, { id:12, pId:1, name:"parentNode 12",isParent:true}, { id:121, pId:12, name:"leafNode 121"}, { id:13, pId:1, name:"parentNode 13", isParent:true}, { id:2, pId:0, name:"parentNode 2", isParent:true} ]; $(document).ready(function(){ $.fn.zTree.init($("#treeDemo"), setting, zNodes); }); </SCRIPT> </body> </html>
testServlet.java
package com.test; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.alibaba.fastjson.JSON; import com.alibaba.fastjson.JSONArray; import com.alibaba.fastjson.JSONObject; public class testServlet extends HttpServlet{ @Override public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } @Override public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String id = request.getParameter("id"); String name = request.getParameter("name"); String level = request.getParameter("level"); String otherParam = request.getParameter("otherParam"); System.out.println(id + "|" + name + "|" + level + "|" + otherParam); List<HashMap<String,Object>> list = new ArrayList<HashMap<String,Object>>(); for(int i = 0; i < 5; i++){ HashMap<String,Object> hm = new HashMap<String,Object>(); //最外层,父节点 hm.put("id",id+i);//id属性 ,数据传递 hm.put("name", id+i); //name属性,显示节点名称 hm.put("pId", id); list.add(hm); } response.getWriter().write(JSON.toJSONString(list)); } }
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <display-name></display-name> <servlet> <servlet-name>testServlet</servlet-name> <servlet-class>com.test.testServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>testServlet</servlet-name> <url-pattern>/test</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app>
Rendering:
The above is about jquery asynchronous loading. I hope it will be helpful to everyone learning jquery programming.