rvview.setOnScrollListener(new RecyclerView.OnScrollListener() {
    @Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
        super.onScrollStateChanged(recyclerView, newState);
RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
//判斷是當前layoutManager是否為LinearLayoutManager
 
        // 只有LinearLayoutManager才有查詢第一個和最後一個可見view位置的方法
if (layoutManager instanceof LinearLayoutManager) {
            LinearLayoutManager linearManager = (LinearLayoutManager) layoutManager;
//獲取最後一個可見view的位置
int lastItemPosition = linearManager.findLastVisibleItemPosition();
//獲取第一個可見view的位置
int firstItemPosition 
 
= linearManager.findFirstVisibleItemPosition();
if (lastItemPosition > 10) {
                tvCount.setVisibility(View.VISIBLE);
tvCount.setText(lastItemPosition + "\n一\n" + list.size());
shouCount = true;
} else {
                shouCount = false;
tvCount.setVisibility(View.GONE);
}
            switch 
 
(newState) {
                case RecyclerView.SCROLL_STATE_IDLE:
                    if (shouCount) {
                        tvCount.setText("一\n" + "↑\n頂部");
}
                    break;
}
            LogUtils.LogE("setOnScrollListener", lastItemPosition + "   " + firstItemPosition);
}
    }

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