EXT TREE CHECK

var Tree = Ext.tree;        
    var tree = new Tree.TreePanel({        
        el:'tree-div',        
        useArrows:true,        
        autoScroll:true,        
        animate:true,        
        enableDD:true,        
        containerScroll: true,         
        loader: new Tree.TreeLoader({        
        dataUrl:'treecheckjson.jsp'       
        })        
    });        
   
     tree.on('checkchange', function(node, checked) {           
        node.expand();           
        node.attributes.checked = checked;           
        node.eachChild(function(child) {           
            child.ui.toggleCheck(checked);           
            child.attributes.checked = checked;           
            child.fireEvent('checkchange', child, checked);           
        });           
    }, tree);        
        
    var root = new Tree.AsyncTreeNode({        
        text: 'Ext JS',        
        draggable:false,     
        checked:false,    
        id:'0'       
    });        
    tree.setRootNode(root);       
        
    tree.render();        
    root.expand();      
 //带复选框(checkbox)的树       
//改编自ExtJs 自带的tree例子，选中父节点后，所有子节点会自动选上。    
//该例子点击父节点如果速度过快，有时候不会自动选中子节点！   
var checkedNodes = tree.getChecked();//tree必须事先创建好.    
var s = [];    
for(var i=0;i<checkedNodes.length;i++){    
s.push(checkedNodes[i].id)    
}   //得到里面选中的node id 值数组

checkchange:function(_node,_checked) {
		var _isexpanded = _node.isExpanded();
		if(!_isexpanded) {
			_node.expand(false,false);
		}
		if(_node.childNodes && _node.childNodes.length > 0) {
			for(i = 0; i < _node.childNodes.length; i++) {
				if(_node.childNodes[i].getUI().isChecked() !== _checked) {
					_node.childNodes[i].getUI().toggleCheck();
				}
			}
		}
		if(!_isexpanded) {
			_node.collapse(false,false);
		}
	},

我的树根节点下只有两层~~

传送门：http://www.iteye.com/topic/617755

不解释