extjs tree异步加载 完整版

//创建JSONTree.java
package com.tree;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;

import net.sf.json.JSONArray;

import com.luke.hm.sf.ConnectionPool;

public class JSONTree{
    private String PID;
   
    public String getJSONString(){
   
        Connection conn =null;
        Statement st = null;
        ResultSet rs = null;
        ArrayList TreeNodeArray = null;
       
        String SQLString = "SELECT * FROM S_MLS WHERE PID="+this.PID+" ORDER BY DID";   
           
        try
        {
       
            conn = ConnectionPool.getConnection();
            st = conn.createStatement();
               
            rs = st.executeQuery("SELECT PID FROM S_MLS WHERE PID>0 Group By PID Order By PID");           
           
            StringBuffer parentIDBuffer =new StringBuffer();
            parentIDBuffer.append("|");        
            while(rs.next())
            {
                parentIDBuffer.append(rs.getString("PID"));
                parentIDBuffer.append("|");
            }
            //得到所有的parentDID列表（这是一个巧妙的算法^_^）
            String parentIDString = parentIDBuffer.toString();        
//            System.out.println(parentIDString);
            rs = st.executeQuery(SQLString);   
            TreeNodeArray = new ArrayList();
           
            while(rs.next())
            {
                JSONTreeNode TreeNode = new JSONTreeNode();
                TreeNode.setId(rs.getString("DID"));
                TreeNode.setText(rs.getString("JDMC"));
                TreeNode.setDescription(rs.getString("JDMC"));         
                TreeNode.setHref("rightframe.jsp?did="+rs.getString("DID").toString());
                TreeNode.setHrefTarget("rightFrame");
//                System.out.println(rs.getString("DID"));
//                System.out.println(parentIDString.indexOf("|"+rs.getString("DID")+"|"));
                if (parentIDString.indexOf("|"+rs.getString("DID")+"|")>=0) //父节点
                    {
                        TreeNode.setCls("folder");
                        TreeNode.setLeaf(false);
                        TreeNode.setExpandable(false);
                    }
                    else //子节点
                   {
                        TreeNode.setCls("file");
                        TreeNode.setLeaf(true);
                        TreeNode.setExpandable(false);
                    }
                    TreeNodeArray.add(TreeNode);
            }
           
//            System.out.println(TreeNodeArray.size());
//            System.out.println(JSONArray.fromObject(TreeNodeArray));
           
          
            JSONArray jsonarr = JSONArray.fromObject(TreeNodeArray); //得到JSON数组    
            return jsonarr.toString();//返回JSON数据
        }
        catch(Exception e)
        {
            System.out.println("getJSONString() of JSONTree.java throws : "+e.toString());
            return "";
        }finally{
        try {
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
        }
       
       
       
    }  


    public String getPID() {
        return PID;
    }

    public void setPID(String pid) {
        PID = pid;
    }
    public static void main(String[] args) {
//    JSONTree tree = new JSONTree();
//    tree.setPID("1");
//    String tt = tree.getJSONString();
//    System.out.println(tt);
    }
}

//创建JSONTreeNode
package com.tree;

import java.io.Serializable;

public class JSONTreeNode implements Serializable{

    private static final long serialVersionUID = 1L;

    public static void main(String[] args) {
   
    }
   
     private String id;            //ID
     private String text;          //节点显示
     private String cls;           //图标
     private boolean leaf;         //是否叶子
     private String href;          //链接
     private String hrefTarget;    //链接指向
     private boolean expandable;   //是否展开
     private String description;   //描述信息

public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public String getCls() {
return cls;
}
public void setCls(String cls) {
this.cls = cls;
}
public boolean isLeaf() {
return leaf;
}
public void setLeaf(boolean leaf) {
this.leaf = leaf;
}
public String getHref() {
return href;
}
public void setHref(String href) {
this.href = href;
}
public String getHrefTarget() {
return hrefTarget;
}
public void setHrefTarget(String hrefTarget) {
this.hrefTarget = hrefTarget;
}
public boolean isExpandable() {
return expandable;
}
public void setExpandable(boolean expandable) {
this.expandable = expandable;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public static long getSerialVersionUID() {
return serialVersionUID;
}
    
         //get、set方法。略。

}
//创建index.jsp
<%@page contentType="text/html; charset=GBK"%>
<%@page import="com.luke.hm.tree.EJBContext"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
   
    <title>My JSP 'index.jsp' starting page</title>
   
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">   
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<link rel="stylesheet" type="text/css" href="<%=EJBContext.getRootPath()%>/ext/resources/css/ext-all.css"/>
<script type="text/javascript" src="<%=EJBContext.getRootPath()%>/ext/adapter/ext/ext-base.js"></script>
<script type="text/javascript" src="<%=EJBContext.getRootPath()%>/ext/ext-all.js"></script>
<script type="text/javascript" src="./mytree.js"></script>
  </head>
 
  <body>
<table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0" onContextMenu="return false;">
<tr>
   <td align="left" valign="top" >
      <!--树的填充区域-->
      <div id="tree_div" style="height:101%;width:100%"></div>
   </td>
</tr>
</table>

  </body>
</html>
//创建Tree.jsp
<%@ page language="java" pageEncoding="GBK"%>

<jsp:useBean class="com.tree.JSONTree" id="JSONTree"></jsp:useBean>

<%
String PID = "";

if (request.getParameter("DID")!=null)
{
    PID = request.getParameter("DID").toString();
}

JSONTree.setPID(PID);
// System.out.println(JSONTree.getJSONString());
%>

<%=JSONTree.getJSONString()%>
//创建mytree.js
Ext.onReady(function(){

   var Tree = Ext.tree;

   //定义根节点的Loader
   var treeloader=new Tree.TreeLoader({dataUrl:'tree.jsp?DID=1'});

   //异步加载根节点
   var rootnode=new Tree.AsyncTreeNode({
        id:'1',
        text:'目录树根节点'
                });
    
   var treepanel = new Tree.TreePanel({
                //renderTo:"tree_div",//如果使用renderTo，则不能使用setRootNode()方法，需要在TreePanel中设置root属性。
                el:'tree_div',        //填充区域
                rootVisible:true,     //隐藏根节点
                border:true,          //边框
                animate:true,         //动画效果
                autoScroll:true,      //自动滚动
                enableDD:false,       //拖拽节点             
                containerScroll:true,
                loader:treeloader            
            });

   //设置根节点
   treepanel.setRootNode(rootnode);

   //响应事件，传递node参数
   treepanel.on('beforeload',
                function(node){
                   treepanel.loader.dataUrl='tree.jsp?DID='+node.id;    //定义子节点的Loader   
                });

   treepanel.render();           
   rootnode.expand(false,false);
});


别忘记把json.jar加进去
库表设计
DID    PID     JDMC

评论

5 楼 java麦克斯泰 2011-09-21  

getJSONString（）

这个方法都没调用 不是完整 例子我 晕 为啥 都不开源呢

4 楼 liuwei8728 2010-04-28  

实在看不出算法巧妙在哪 
先补在拆     完全没必要

3 楼 helloandy2009 2010-01-06  

import net.sf.json.JSONArray;  这个类是干啥用的

2 楼 hanjiangit 2009-11-21  

貌似不行   啊

1 楼 leafxf 2009-01-04  

很好，有收获