PullToRefresh上啦刷新下拉加载

//首先导入libary包然后build版本更改ImageLoader包导入Gson包导入写入MyApp类

package com.example.zhangshaohang1511b20171117;import android.os.AsyncTask;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View;import android.widget.ListView;import com.google.gson.Gson;import com.handmark.pulltorefresh.library.PullToRefreshBase;import com.handmark.pulltorefresh.library.PullToRefreshListView;import java.util.List;public class MainActivity extends AppCompatActivity {    private PullToRefreshListView lv;    private TextUtils utils;    private static final String JSON_URL = "http://gank.io/api/data/%E7%A6%8F%E5%88%A9/10/1";    private int peaNam=1;    private List<SuperClass.ResultsBean> results;    private MyAdapter adapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initView();        lv.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener<ListView>() {            @Override            public void onRefresh(PullToRefreshBase<ListView> refreshView) {                peaNam=1;                new AsyncTask<String, Integer, String>() {                    @Override                    protected String doInBackground(String... strings) {                        String str=utils.getJsonget(JSON_URL+peaNam);                        return str;                    }                    @Override                    protected void onPostExecute(String s) {                        super.onPostExecute(s);                        Gson gson=new Gson();                        SuperClass fromJson = gson.fromJson(s, SuperClass.class);                        results = fromJson.getResults();                        adapter = new MyAdapter(results,MainActivity.this);                        lv.setAdapter(adapter);                        lv.onRefreshComplete();                    }                }.execute();            }        });        lv.setOnLastItemVisibleListener(new PullToRefreshBase.OnLastItemVisibleListener() {            @Override            public void onLastItemVisible() {                peaNam++;                new AsyncTask<String, Integer, String>() {                    @Override                    protected String doInBackground(String... strings) {                        String str=utils.getJsonget(JSON_URL+peaNam);                        return str;                    }                    @Override                    protected void onPostExecute(String s) {                        super.onPostExecute(s);                        Gson gson=new Gson();                        SuperClass fromJson = gson.fromJson(s, SuperClass.class);                        List<SuperClass.ResultsBean> aresults = fromJson.getResults();//                        MyAdapter adapter = new MyAdapter(aresults,MainActivity.this);//                        lv.setAdapter(adapter);                        results.addAll(aresults);                        adapter.notifyDataSetChanged();                    }                }.execute();            }        });    }    private void initView() {        //找到控件        lv = (PullToRefreshListView) findViewById(R.id.lv);        utils = new TextUtils();        new AsyncTask<String, Integer, String>() {            @Override            protected String doInBackground(String... strings) {                String str=utils.getJsonget(JSON_URL);                return str;            }            @Override            protected void onPostExecute(String s) {                super.onPostExecute(s);                Gson gson=new Gson();                SuperClass fromJson = gson.fromJson(s, SuperClass.class);                List<SuperClass.ResultsBean> results = fromJson.getResults();                MyAdapter adapter = new MyAdapter(results,MainActivity.this);                lv.setAdapter(adapter);            }        }.execute();    }}

//网络请求类

package com.example.zhangshaohang1511b20171117;import java.io.ByteArrayOutputStream;import java.io.InputStream;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.net.URLConnection;/** * Created by 心所在梦就在 on 2017/11/17. */public class TextUtils {    private static final String JSON_URL = "http://gank.io/api/data/%E7%A6%8F%E5%88%A9/10/1";    public String getJsonget(String param){        String data = "";        try {            URL url = new URL(param);            HttpURLConnection Conn = (HttpURLConnection) url.openConnection();            Conn.setConnectTimeout(5000);            Conn.setReadTimeout(5000);            int responseCode = Conn.getResponseCode();            if (responseCode==200){                InputStream inputStream=Conn.getInputStream();                ByteArrayOutputStream outputStream=new ByteArrayOutputStream();                byte[] b=new byte[1024];                int len=-1;                while ((len=inputStream.read(b))!=-1){                    outputStream.write(b, 0, len);                }                data = outputStream.toString();            }        } catch (Exception e) {            e.printStackTrace();        }        return  data;    }}

//适配器

package com.example.zhangshaohang1511b20171117;import android.content.Context;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.TextView;import com.nostra13.universalimageloader.core.ImageLoader;import java.util.List;/** * Created by 心所在梦就在 on 2017/11/16. */public class MyAdapter extends BaseAdapter {    List<SuperClass.ResultsBean> list;    Context context;    public MyAdapter(List<SuperClass.ResultsBean> list, Context context) {        this.list = list;        this.context = context;    }    @Override    public int getCount() {        return list.size();    }    @Override    public Object getItem(int position) {        return list.get(position);    }    @Override    public long getItemId(int position) {        return position;    }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        ViewHolder holder;        View view;        if (convertView==null){            holder=new ViewHolder();            view= View.inflate(context,R.layout.item,null);            holder._id = (TextView) view.findViewById(R.id._id);            holder.createdAt = (TextView) view.findViewById(R.id.createdAt);            holder.desc = (TextView) view.findViewById(R.id.desc);            holder.publishedAt = (TextView) view.findViewById(R.id.publishedAt);            holder.source = (TextView) view.findViewById(R.id.source);            holder.type = (TextView) view.findViewById(R.id.type);            holder.url = (TextView) view.findViewById(R.id.url);            holder.who = (TextView) view.findViewById(R.id.who);            holder.img = (ImageView) view.findViewById(R.id.img);            view.setTag(holder);        }else{            view=convertView;            holder= (ViewHolder) view.getTag();        }        SuperClass.ResultsBean bean = list.get(position);        holder._id.setText(list.get(position).get_id());        holder.createdAt.setText(list.get(position).get_id());        holder.desc.setText(list.get(position).get_id());        holder.publishedAt.setText(list.get(position).get_id());        holder.source.setText(list.get(position).get_id());        holder.type.setText(list.get(position).get_id());        holder.url.setText(list.get(position).get_id());        holder.who.setText(list.get(position).get_id());        ImageLoader.getInstance().displayImage(bean.getUrl(),holder.img);        return view;    }    class ViewHolder{        TextView _id,createdAt,desc,publishedAt,source,type,url,who;        ImageView img;    }}

//MyApp

package com.example.zhangshaohang1511b20171117;import android.app.Application;import com.nostra13.universalimageloader.core.ImageLoader;import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;/** * Created by 心所在梦就在 on 2017/11/17. */public class MyApp extends Application {    @Override    public void onCreate() {        super.onCreate();        ImageLoaderConfiguration build=new ImageLoaderConfiguration.Builder(this).build();        ImageLoader.getInstance().init(build);    }}

//布局文件

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context="com.example.zhangshaohang1511b20171117.MainActivity">    <com.handmark.pulltorefresh.library.PullToRefreshListView        android:id="@+id/lv"        android:layout_width="match_parent"        android:layout_height="match_parent"        /></RelativeLayout>

//适配器item XML文件

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">    <ImageView        android:id="@+id/img"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/_id"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/createdAt"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/desc"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/publishedAt"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/source"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/type"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/url"        android:layout_width="wrap_content"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/who"        android:layout_width="wrap_content"        android:layout_height="wrap_content" /></LinearLayout>