实现代码：

//RecyclerView的滑动监听
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
    //当RecyclerView滑动时触发
    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
        //获取可见item个数
        int lastVisibleItemPosition =
                 linearLayoutManager.findLastVisibleItemPosition();
        //说明是最后一条数据
        if (lastVisibleItemPosition + 1 == adapter.getItemCount()) {
            Snackbar.make(mRecyclerView, "一次只加载20条，查看更多请刷新哦。",
                    Snackbar.LENGTH_SHORT).show();
        }
    }
});

如何监听RecyclerView划到最后一条数据