最简单的extjs 树

Ext.onReady(function(){
	var tree = new Ext.tree.TreePanel({
		el:'tree-div'
	});
	var root = new Ext.tree.TreeNode({text:'我是跟'});
	var node1 = new Ext.tree.TreeNode({text:'我是根的第一个枝'});
	var node2 = new Ext.tree.TreeNode({text:'我是枝的第一个叶子'});
	root.appendChild(node1);
	node1.appendChild(node2);
	tree.setRootNode(root); //
	tree.render();
	root.expand(true,true);//自动展开
});