滑动监听，判断是否滑动到了最后一个条目

recyclerView.setOnScrollListener(new RecyclerView.OnScrollListener() {  
    //用来标记是否正在向最后一个滑动  
    boolean isSlidingToLast = false;  

    @Override  
    public void onScrollStateChanged(RecyclerView recyclerView, int newState) {  
        super.onScrollStateChanged(recyclerView, newState);
        //设置什么布局管理器,就获取什么的布局管理器
        LinearLayoutManager manager = (LinearLayoutManager) recyclerView.getLayoutManager();  
        // 当停止滑动时  
        if (newState == RecyclerView.SCROLL_STATE_IDLE) {  
            //获取最后一个完全显示的ItemPosition ,角标值 
            int lastVisibleItem = manager.findLastCompletelyVisibleItemPosition();  
            //所有条目,数量值
            int totalItemCount = manager.getItemCount();  

            // 判断是否滚动到底部，并且是向右滚动  
            if (lastVisibleItem == (totalItemCount - 1) && isSlidingToLast) {  
                //加载更多功能的代码  
                
            }  
        }  
    }  

    @Override  
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {  
        super.onScrolled(recyclerView, dx, dy);  
        //dx用来判断横向滑动方向，dy用来判断纵向滑动方向  
        //dx>0:向右滑动,dx<0:向左滑动
        //dy>0:向下滑动,dy<0:向上滑动
        if (dy > 0) {  
            isSlidingToLast = true;  
        } else {  
            isSlidingToLast = false;  
        }  
    }  
});  

或者用下列方法

public abstract class OnLoadMoreListener extends RecyclerView.OnScrollListener {
    private LinearLayoutManager layoutManager;
    private int itemCount, lastPosition, lastItemCount;
    public abstract void onLoadMore();
    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        if (recyclerView.getLayoutManager() instanceof LinearLayoutManager) {
            layoutManager = (LinearLayoutManager) recyclerView.getLayoutManager();
            itemCount = layoutManager.getItemCount();
            lastPosition = layoutManager.findLastCompletelyVisibleItemPosition();
        } else {
            Log.e("OnLoadMoreListener", "The OnLoadMoreListener only support LinearLayoutManager");
            return;
        }
        if (lastItemCount != itemCount && lastPosition == itemCount - 1) {
            lastItemCount = itemCount;
            this.onLoadMore();
        }
    }
}