el-tree树组件 点击箭头展开关闭节点 展开的是所有子孙节点

<el-tree :data="data" :props="defaultProps" @node-click="handleNodeClick" class="checked-bottom-tree"  default-expand-all node-key="id" ref="tree" :expand-on-click-node="false"
 :default-expanded-keys="expandArray" @node-expand="handleNodeExpand">
</el-tree>
methods: {
	 handleNodeExpand (data,node,component) {
            for (var i = 0; i < this.$refs.tree.store._getAllNodes().length; i++) {
                this.$refs.tree.store._getAllNodes()[i].expanded = true;
            }
        }
    ----------------------------------------------------------------------
     for (var i = 0; i < node.childNodes.length; i++) {
                node.childNodes[i].expanded = true;
            }
}