ExtJS -- 改变树节点图标 tree

<style>
.x-tree-node .nodeicon {
background-image: url(resources/bl_images/16-member-add.png);
}
</style>

this.loader.on('load', function(tree, node) {
var nodes = node.childNodes;
for (var i = 0; i < nodes.length; i++) {
var el = nodes[i].getUI().getIconEl();
(new Ext.Element(el)).addClass("nodeicon");//或el.src='back.gif';
}
});