展示数据,上拉加载,下拉刷新,一定要导入library.

主方法中的代码

private String name;
 private  String news_url;
private List<news> newslist;
 private PullToRefreshListView lv;
 private   Myadap myadap;

 @Override
 public void onCreate(@Nullable Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     //接收传过来的URL
     Bundle bundle=getArguments();
     name= (String) bundle.get("name");
     news_url= (String) bundle.get("url");

 }

 @Nullable
 @Override
 public View onCreateView(LayoutInflater inflater, @Nullable final ViewGroup container, @Nullable Bundle savedInstanceState) {
     View view=inflater.inflate(R.layout.pager_item,null);
     lv= (PullToRefreshListView) view.findViewById(R.id.lv);
     //设置上拉加载和下拉刷新
     lv.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener<ListView>() {
         @Override
         public void onRefresh(PullToRefreshBase<ListView> refreshView) {
             getJson();
             lv.onRefreshComplete();

         }
     });
     lv.setOnLastItemVisibleListener(new PullToRefreshBase.OnLastItemVisibleListener() {
         @Override
         public void onLastItemVisible() {
             Load();
         }
     });
     //调用解析数据的方法
     getJson();
     return view;
 }

 private void getJson() {
     new AsyncTask<String,Integer,String>(){
         @Override
         protected String doInBackground(String... params) {
             String url=params[0];
             String json=new NetHowoder().getjsonBy(url);

             return json;
         }

         @Override
         protected void onPostExecute(String s) {
             super.onPostExecute(s);
             Log.d("TAG",s+"-----------------");
             Gson gson=new Gson();
             UserBean userBean = gson.fromJson(s, UserBean.class);
             newslist = userBean.getNewslist();
             //设置适配器
             myadap= new Myadap(getActivity(), newslist);
             lv.setAdapter(myadap);
             myadap.notifyDataSetChanged();

         }
     }.execute(news_url);
 }
 private  void Load(){
     new AsyncTask<String,Integer,String>(){
         @Override
         protected String doInBackground(String... params) {
             String url=params[0];
             String json=new NetHowoder().getjsonBy(url);
             return json;
         }

         @Override
         protected void onPostExecute(String s) {
             super.onPostExecute(s);
             Log.d("TAG",s+"-----------------");
             Gson gson=new Gson();
             UserBean userBean = gson.fromJson(s, UserBean.class);
             List<news> newslist3 = userBean.getNewslist();
             newslist.addAll(newslist3);
             myadap.notifyDataSetChanged();

         }
     }.execute(news_url);
 }

///XML布局中写上 PullToRefreshListView

<com.handmark.pulltorefresh.library.PullToRefreshListView
    xmlns:ptr="http://schemas.android.com/apk/res-auto"
    android:id="@+id/lv"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
  />