android RecyclerView获得单个Item的ViewHolder

我们在使用RecyclerView时，有时候还需要获取某个Item的viewHolder，具体如下：

LinearLayoutManager layoutManager= new LinearLayoutManager(activity);

int firstItemPosition = layoutManager.findFirstVisibleItemPosition();        if (position - firstItemPosition >= 0) {            //得到要更新的item的view            View view = mRecyclerView.getChildAt(position - firstItemPosition+1);            if (null != mRecyclerView.getChildViewHolder(view)){                ProductsViewHolder viewHolder = (ProductsViewHolder)mRecyclerView.getChildViewHolder(view);//do something           }

position就是当前item的位置