ext高分悬赏,高手何在啊解决方案 _JavaScript

ext高分悬赏,高手何在啊
下面那错了,怎么就是运行不成功，我用的是ext4.0的版本，文件路径都好着呢
想做个树形目录怎么弄

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>tree.html</title>
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="this is my page">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<link rel="stylesheet" type="text/css" href="css/ext-all.css"/>
<script type="text/javascript" src="js/bootstrap.js"></script>
<script type="text/javascript" src="js/ext-all.js"></script>
<script>
Ext.onReady(function(){
var tree=new Ext.tree.TreePanel({
el:'tree'
});
var root=new Ext.tree.TreeNode({
text:'我是根'});
tree.setRootNode(root);
tree.render();
});
</script>
</head>

<body>
<div id="tree"></div>
</body>
</html>

------解决方案--------------------
是不是漏掉了Ext.QuickTips.init(); ？？？

------解决方案--------------------
学习一下
------解决方案--------------------
楼主的写法怎么是2.2的 4.0和2.2的完全不一样
看如下demo

JScript code

var store = Ext.create('Ext.data.TreeStore', {
            root : {
                expanded : true,
                children : [{
                            text : "detention",
                            leaf : true
                        }, {
                            text : "homework",
                            expanded : true,
                            children : [{
                                        text : "book report",
                                        leaf : true
                                    }, {
                                        text : "alegrbra",
                                        leaf : true
                                    }]
                        }, {
                            text : "buy lottery tickets",
                            leaf : true
                        }]
            }
        });

Ext.create('Ext.tree.Panel', {
            title : 'Simple Tree',
            width : 200,
            height : 150,
            store : store,
            rootVisible : false,
            renderTo : Ext.getBody()
        });

------解决方案--------------------
导入的EXT类库文件不完整