Recyclerview的下拉刷新和上拉加载

布局

<android.support.v4.widget.SwipeRefreshLayout android:id="@+id/sw" android:layout_width="wrap_content" android:layout_height="wrap_content" >  <android.support.v7.widget.RecyclerView        android:id="@+id/rv"        android:layout_width="match_parent"        android:layout_height="wrap_content"        /></android.support.v4.widget.SwipeRefreshLayout>

设置监听

sw.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {     @Override     public void onRefresh() {         presnter.login(1);         sw.setRefreshing(false);     } });
添加底部监听

mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
    @Override
    public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
        //当前RecyclerView显示出来的最后一个的item的position
        int lastPosition = -1;
 
        //当前状态为停止滑动状态SCROLL_STATE_IDLE时
        if(newState == RecyclerView.SCROLL_STATE_IDLE){
            RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
            if(layoutManager instanceof GridLayoutManager){
                //通过LayoutManager找到当前显示的最后的item的position
                lastPosition = ((GridLayoutManager) layoutManager).findLastVisibleItemPosition();
            }else if(layoutManager instanceof LinearLayoutManager){
                lastPosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            }
            //时判断界面显示的最后item的position是否等于itemCount总数-1也就是最后一个item的position
            //如果相等则说明已经滑动到最后了
            if(lastPosition == recyclerView.getLayoutManager().getItemCount()-1){
                Toast.makeText(RecyclerActivity.this, "滑动到底了", Toast.LENGTH_SHORT).show();
            }
 
        }
    }
 
    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
 
    }
 
});