public function transform($item){
        //查询数据
        $position = AdminAccess::where('id',$item)->first();
        $relation = [];
        $relation[] = $position;
        $pid = $position->pid;
        //循环子级pid，查找所有父级id
        while ($top = AdminAccess::where(['id' => $pid])->first()) {
            $pid = $top->pid;
            //从头部添加数组元素，与 array_push 相似，一个是头部一个是尾部
            array_unshift($relation, $top);
        }
        foreach ($relation as $k => $v){
            $data[] = $v->id ;
        }
        return $data;
    }