Android关于RecyclerView加载更多问题

网上大多数 RecyclerView.OnScrollListener的判断如下：

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);

lastVisibleItemPosition = mLinearLayoutManager.findLastVisibleItemPosition();
visibleItemCount = recyclerView.getChildCount();
totalItemCount = mLinearLayoutManager.getItemCount();
firstVisibleItemPosition = mLinearLayoutManager.findFirstVisibleItemPosition();
lastVisibleItemPosition = mLinearLayoutManager.findLastVisibleItemPosition();

if(isLoading){
            if(totalItemCount > previousTotal){
            isLoading = false;
            previousTotal = totalItemCount;
        }

}
// if (!isLoading && totalItemCount-visibleItemCount <= firstVisibleItemPosition ){ //(1)

        if (!isLoading && lastVisibleItemPosition ==totalItemCount-1){ //(2)
                        //加载更多逻辑
            }

在RecyclerView.OnScrollListener中，不论是方式(1)还是(2)，在item数据不足以充满屏幕时都会自动加载更多，直到充满屏幕才停下，求教如何在item数据不足一屏幕时判断加载更多逻辑

http://blog.csdn.net/lihongxiangleo/article/details/50300545