通过PullToRefresh展示listView+数据库

写两个Base类，方便调用
一个Activity里面调用的：

package com.ang.lianxi;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;


public abstract class BaseActivity extends FragmentActivity {
    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(bindLayout());
        initView();
        initData();;
        bindEvent();
    }
    public abstract int bindLayout();
    public abstract void initView();

    public abstract void initData();
    public abstract void bindEvent();
}

一个fragment里面调用的：

package com.ang.lianxi;

import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


public abstract class BaseFragment extends Fragment {
    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(bindLayout(),container,false);
    }

    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        initView();
        initData();
        bindEvent();
    }
    //绑定视图
    protected abstract int bindLayout();
    //绑定组件
    protected abstract void initView();
    //操作数据
    protected abstract void initData();
    //设置监听
    protected abstract void bindEvent();

}

写一个判断有没有网络的方法，在写一个AsynTask请求网络的方法，方便调用！

package com.ang.lianxi.http;

import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;


public class Http {
    //判断有没有网的方法
    public static boolean isWorkConnected(Context con){
        if(con!=null){
            //获取连接管理器
            ConnectivityManager manager = (ConnectivityManager) con.getSystemService(Context.CONNECTIVITY_SERVICE);
            //获取网络状态
            NetworkInfo info = manager.getActiveNetworkInfo();
            if(info!=null){
                //判断网络是否可用
                return info.isAvailable();
            }
        }
        return false;
    }
    public static void httpAsynTask(String strUrl,final CallBackString backString){
        new AsyncTask<String,Integer,String>(){

            @Override
            protected String doInBackground(String... strings) {
                return HttpGet(strings[0]);
            }
            @Override
            protected void onPostExecute(String s) {
                super.onPostExecute(s);
                //接口回调的方法
                backString.getData(s);
            }
        }.execute(strUrl);
    }
    //接口
    public interface CallBackString{
        void  getData(String s);
    }
    public static String HttpGet(String strUrl){
        try {
            //设置url
            URL url=new URL(strUrl);

            HttpURLConnection connection= (HttpURLConnection) url.openConnection();
            //设置get请求
            connection.setRequestMethod("GET");
            //设置从主机读取数据超时
            connection.setReadTimeout(5000);
            //设置连接主机超时时间
            connection.setConnectTimeout(5000);
            int code = connection.getResponseCode();
            if(code==200){
                //得到数据
                InputStream stream = connection.getInputStream();
                BufferedReader reader=new BufferedReader(new InputStreamReader(stream,"utf-8"));
                //拼接数据
                StringBuilder builder=new StringBuilder();
                String str="";
                while ((str=reader.readLine())!=null){
                    builder.append(str);
                }
                //返回数据
                return builder.toString();
            }
            //关闭连接
            connection.disconnect();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }


}

数据库

package com.ang.lianxi.sql;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;


public class MySqlite extends SQLiteOpenHelper {
    public MySqlite(Context context) {
        super(context, "la.db", null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {
    			//你要添加的数据
            sqLiteDatabase.execSQL("create table news(id integer primary key autoincrement,name text,tit text,img text)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

    }
}

数据库配合着Dao使用：
这里我只写了两个方法：一个添加、一个查询

package com.ang.lianxi.sql;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;


public class Dao {

    private final SQLiteDatabase db;

    public Dao(Context con){
        MySqlite mySqlite=new MySqlite(con);
        db = mySqlite.getWritableDatabase();
    }
    public long insert(String table, String nullColumnHack, ContentValues values) {
        return db.insert(table,nullColumnHack,values);
    }
    public Cursor query(String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy) {
        return db.query(table,columns,selection,selectionArgs,groupBy,having,orderBy);
    }

}

我用的是ImageLoader加载图片

package com.ang.lianxi.app;

import android.app.Application;
import android.graphics.Bitmap;
import android.os.Environment;

import com.ang.lianxi.R;
import com.nostra13.universalimageloader.cache.disc.impl.UnlimitedDiskCache;
import com.nostra13.universalimageloader.cache.disc.naming.Md5FileNameGenerator;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import com.nostra13.universalimageloader.core.display.CircleBitmapDisplayer;

import java.io.File;


public class App extends Application {
    @Override
    public void onCreate() {
        super.onCreate();
        String path=Environment.getExternalStorageDirectory().getPath()+"/TuPian";
        File file=new File(path);
        DisplayImageOptions options=new DisplayImageOptions.Builder()
                // 正在加载时显示的占位图
                .showImageOnLoading(R.mipmap.zhan)
                // 加载失败时显示的占位图
                .showImageOnFail(R.mipmap.shibai)
                //设置圆形
                .displayer(new CircleBitmapDisplayer())
                // bitmap的质量，默认为ARGB_8888
                .bitmapConfig(Bitmap.Config.ARGB_8888)
                .build();
        ImageLoaderConfiguration loaderConfiguration=new ImageLoaderConfiguration.Builder(this)
                //把我们写的设置添加到构建中
                .defaultDisplayImageOptions(options)
                .memoryCacheExtraOptions(200, 200)//配置内存缓存图片的尺寸
                .memoryCacheSize(2 * 1024 * 1024)//配置内存缓存的大小
                .threadPoolSize(3)//配置加载图片的线程数
                .threadPriority(1000)//配置线程的优先级
                .diskCache(new UnlimitedDiskCache(file))//UnlimitedDiskCache 限制这个图片的缓存路径
                .diskCacheFileCount(50)//配置sdcard缓存文件的数量
                .diskCacheFileNameGenerator(new Md5FileNameGenerator())//MD5这种方式生成缓存文件的名字
                .diskCacheSize(50 * 1024 * 1024)//在sdcard缓存50MB
                .build();//完成
        //获得实例
        ImageLoader imageLoader=ImageLoader.getInstance();
        //初始化
        imageLoader.init(loaderConfiguration);

    }
}

主页面我写的是一个类似于QQ页面的
先看下布局:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:orientation="vertical"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">



    <android.support.v4.widget.DrawerLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <!--主页面-->
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical"
            >
            <FrameLayout
                android:layout_width="match_parent"
                android:layout_height="0dp"
                android:layout_weight="1"
                android:id="@+id/frag"
                ></FrameLayout>

            <RadioGroup
                android:id="@+id/radi"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal"
                >
                <RadioButton
                    android:id="@+id/radio1"
                    android:layout_width="0dp"
                    android:layout_weight="1"
                    android:layout_height="match_parent"
                    android:gravity="center"
                    android:text="列表"
                    android:background="@drawable/sele"
                    android:button="@null"
                    android:textSize="20sp"
                    android:padding="8dp"
                    />
                <RadioButton
                    android:id="@+id/radio2"
                    android:layout_width="0dp"
                    android:layout_weight="1"
                    android:background="@drawable/sele"
                    android:layout_height="match_parent"
                    android:gravity="center"
                    android:text="表格"
                    android:button="@null"
                    android:textSize="20sp"
                    android:padding="8dp"
                    />
            </RadioGroup>
        </LinearLayout>
        <LinearLayout
            android:layout_gravity="left"
            android:background="#ded3d3"
            android:orientation="vertical"
            android:layout_width="match_parent"
            android:layout_height="match_parent">
            <ImageView
                android:id="@+id/tx"
                android:layout_width="150dp"
                android:layout_height="150dp"
                android:layout_gravity="center"
                />
            <ListView
                android:layout_width="match_parent"
                android:layout_height="0dp"
                android:layout_weight="1"
                android:id="@+id/list"
                ></ListView>
        </LinearLayout>
    </android.support.v4.widget.DrawerLayout>

</LinearLayout>

接下来是Activity里面，加一个侧拉页面(侧拉页面 我就随便展示了一个接口数据)

package com.ang.lianxi;

import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.RadioGroup;

import com.ang.lianxi.adapter.MyActivityAdapter;
import com.ang.lianxi.bean.Datass;
import com.ang.lianxi.bean.NewsBean;
import com.ang.lianxi.frag.FragList;
import com.ang.lianxi.frag.FragNull;
import com.ang.lianxi.http.Http;
import com.google.gson.Gson;
import com.nostra13.universalimageloader.core.ImageLoader;

import java.util.ArrayList;

public class MainActivity extends BaseActivity {


    private RadioGroup radi;
    private FragList f1;
    private FragNull f2;
    private ImageView im;
    private ListView list;
    private String str="http://api.expoon.com/AppNews/getNewsList/type/1/p/1";

    @Override
    public void initView() {
        //找控件
        radi = findViewById(R.id.radi);
        radi.check(radi.getChildAt(0).getId());
        im = findViewById(R.id.tx);
        list = findViewById(R.id.list);
        String ss="http://image.baidu.com/search/down?tn=download&word=download&ie=utf8&fr=detail&url=http%3A%2F%2Fimg5.duitang.com%2Fuploads%2Fitem%2F201410%2F05%2F20141005082835_2RTzn.thumb.700_0.jpeg&thumburl=http%3A%2F%2Fimg2.imgtn.bdimg.com%2Fit%2Fu%3D3846895839%2C2711067435%26fm%3D26%26gp%3D0.jpg";
        //侧拉的 个人头像设置
        ImageLoader.getInstance().displayImage(ss, im);
    }

    @Override
    public int bindLayout() {
        return R.layout.activity_main;
    }

    @Override
    public void initData() {
        FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
        f1 = new FragList();
        f2 = new FragNull();
        transaction.add(R.id.frag, f1);
        transaction.add(R.id.frag, f2);
        transaction.hide(f2).show(f1);
        transaction.commit();
        Http.httpAsynTask(str, new Http.CallBackString() {
            @Override
            public void getData(String s) {
                if(Http.isWorkConnected(MainActivity.this)){
                    Gson gson=new Gson();
                    NewsBean bean = gson.fromJson(s, NewsBean.class);
                    ArrayList<Datass> data = bean.getData();
                    list.setAdapter(new MyActivityAdapter(data,MainActivity.this));
                }

            }
        });
    }

    @Override
    public void bindEvent() {
        radi.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup radioGroup, int i) {
                FragmentTransaction tt = getSupportFragmentManager().beginTransaction();
                switch (i){
                    case R.id.radio1:
                        tt.hide(f2).show(f1);
                        break;
                    case R.id.radio2:
                        tt.hide(f1).show(f2);
                        break;
                }
                tt.commit();
            }
        });
    }
}

适配器我写的是外部的(这里我用了一个listview多条目)，代码如下：

package com.ang.lianxi.adapter;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.ang.lianxi.R;
import com.ang.lianxi.bean.Datass;
import com.nostra13.universalimageloader.core.ImageLoader;

import java.util.ArrayList;


public class MyActivityAdapter extends BaseAdapter {
    private ArrayList<Datass> arr;
    private Context con;

    public MyActivityAdapter(ArrayList<Datass> arr, Context con) {
        this.arr = arr;
        this.con = con;
    }

    @Override
    public int getCount() {
        return arr.size();
    }

    @Override
    public Object getItem(int i) {
        return null;
    }

    @Override
    public long getItemId(int i) {
        return 0;
    }

    @Override
    public int getViewTypeCount() {
        return 4;
    }

    @Override
    public int getItemViewType(int position) {
        return position%4;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        switch (getItemViewType(i)){
            case 0:
                ViewHolder vh;
                if(view==null){
                    view=LayoutInflater.from(con).inflate(R.layout.ce_one, null);
                    vh=new ViewHolder();
                    vh.img=view.findViewById(R.id.img);
                    vh.tit=view.findViewById(R.id.tit);
                    view.setTag(vh);
                }else{
                    vh= (ViewHolder) view.getTag();
                }
                vh.tit.setText(arr.get(i).getNews_title());
                ImageLoader.getInstance().displayImage(arr.get(i).getPic_url(),vh.img);
                break;
            case 1:
                ViewHolder1 vh1;
                if(view==null){
                    view=LayoutInflater.from(con).inflate(R.layout.ce_two, null);
                    vh1=new ViewHolder1();
                    vh1.img=view.findViewById(R.id.img);
                    vh1.tit=view.findViewById(R.id.tit);
                    view.setTag(vh1);
                }else{
                    vh1= (ViewHolder1) view.getTag();
                }
                vh1.tit.setText(arr.get(i).getNews_title());
                ImageLoader.getInstance().displayImage(arr.get(i).getPic_url(),vh1.img);
                break;
            case 2:
                ViewHolder2 vh2;
                if(view==null){
                    view=LayoutInflater.from(con).inflate(R.layout.ce_three, null);
                    vh2=new ViewHolder2();
                    vh2.tit=view.findViewById(R.id.tit);
                    vh2.img=view.findViewById(R.id.img);
                    view.setTag(vh2);
                }else{
                    vh2= (ViewHolder2) view.getTag();
                }
                vh2.tit.setText(arr.get(i).getNews_title());
                ImageLoader.getInstance().displayImage(arr.get(i).getPic_url(),vh2.img);
                break;
            case 3:
                ViewHolder3 vh3;
                if(view==null){
                    view=LayoutInflater.from(con).inflate(R.layout.ce_four, null);
                    vh3=new ViewHolder3();
                    vh3.tit=view.findViewById(R.id.tit);
                    vh3.img=view.findViewById(R.id.img);
                    view.setTag(vh3);
                }else{
                    vh3= (ViewHolder3) view.getTag();
                }
                vh3.tit.setText(arr.get(i).getNews_title());
                ImageLoader.getInstance().displayImage(arr.get(i).getPic_url(),vh3.img);
                break;
        }
        return view;
    }
    static class ViewHolder{
        ImageView img;
        TextView tit;
    }
    static class ViewHolder1{
        ImageView img;
        TextView tit;
    }
    static class ViewHolder2{
        ImageView img;
        TextView tit;
    }
    static class ViewHolder3{
        ImageView img;
        TextView tit;
    }
}

---

接下来是fragment里面的啦
首先布局：
自己提前导一个PullToRefresh 然后把PullToRefresh和自己的项目关联起来

<?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">
    <com.handmark.pulltorefresh.library.PullToRefreshListView
        android:id="@+id/pull"
        android:layout_width="match_parent"
        android:layout_height="match_parent"

        />

</LinearLayout>

布局完了，就是主要的代码啦

package com.ang.lianxi.frag;

import android.content.ContentValues;
import android.database.Cursor;
import android.widget.ListView;
import android.widget.Toast;

import com.ang.lianxi.BaseFragment;
import com.ang.lianxi.R;
import com.ang.lianxi.adapter.MyAdapter;
import com.ang.lianxi.bean.Datas;
import com.ang.lianxi.bean.JsonBean;
import com.ang.lianxi.http.Http;
import com.ang.lianxi.sql.Dao;
import com.google.gson.Gson;
import com.handmark.pulltorefresh.library.PullToRefreshBase;
import com.handmark.pulltorefresh.library.PullToRefreshListView;

import java.util.ArrayList;


public class FragList extends BaseFragment {

    private PullToRefreshListView listv;
    private String str="http://www.xieast.com/api/news/news.php?page=1";

    private ArrayList<Datas> data;
    private MyAdapter adapter;
    private Dao dao;

    @Override
    protected int bindLayout() {
        return R.layout.frag_list;
    }

    @Override
    protected void initView() {
        //找控件
        listv = getActivity().findViewById(R.id.pull);
        //设置模式  BOTH:支持上拉加载 下拉刷新   PULL_FROM_END:仅支持加载更多    PULL_FROM_START:下拉刷新
        listv.setMode(PullToRefreshBase.Mode.BOTH);
        //设置刷新的时候可以滑动
        listv.setScrollingWhileRefreshingEnabled(true);
        dao = new Dao(getActivity());
    }

    @Override
    protected void initData() {
        //判断有没有网络
        boolean workConnected = Http.isWorkConnected(getActivity());
        if(workConnected){
            //有就加载数据
            Http.httpAsynTask(str, new Http.CallBackString() {
                @Override
                public void getData(String s) {
                    Gson gson=new Gson();
                    JsonBean bean = gson.fromJson(s, JsonBean.class);
                    data = bean.getData();
                    //判断有没有数据 有数据就不添加
                    if(dao.query("news",null,null,null,null,null,null).moveToFirst()){

                    }else{
                        //如果没有就添加
                        for (Datas beana : data){
                            ContentValues values = new ContentValues();
                            values.put("tit", beana.getTitle());
                            values.put("name", beana.getAuthor_name());
                            values.put("img", beana.getThumbnail_pic_s());
                            dao.insert("news", null, values);
                        }
                    }
                    //适配器
                    adapter = new MyAdapter(data,getActivity());
                    listv.setAdapter(adapter);
                }
            });
        }else {
            //没有  就查找数据库有没有  数据库有加载数据库
            Cursor cursor = dao.query("news", null, null, null, null, null, null);
            data=new ArrayList<>();
            if(cursor.moveToFirst()){
                do {
                    //name text,tit text,img text
                    String name = cursor.getString(cursor.getColumnIndex("name"));
                    String tit = cursor.getString(cursor.getColumnIndex("tit"));
                    String img = cursor.getString(cursor.getColumnIndex("img"));
                    data.add(new Datas(name,tit,img));
                }while (cursor.moveToNext());
            }
            cursor.close();
            Toast.makeText(getActivity(),"没有网络",Toast.LENGTH_LONG).show();
            //适配器
            adapter=new MyAdapter(data,getActivity());
            listv.setAdapter(adapter);
        }
    }

    @Override
    protected void bindEvent() {
        listv.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2<ListView>() {
            @Override
            public void onPullDownToRefresh(PullToRefreshBase<ListView> refreshView) {
                //判断有没有网络
                if(Http.isWorkConnected(getActivity())){
                    //下拉刷新
                    Http.httpAsynTask(str, new Http.CallBackString() {
                        @Override
                        public void getData(String s) {
                            //解析
                            Gson gson=new Gson();
                            JsonBean bean = gson.fromJson(s, JsonBean.class);
                            data = bean.getData();
                            adapter=new MyAdapter(data,getActivity());
                            listv.setAdapter(adapter);
                            listv.onRefreshComplete();
                        }
                    });
                }else {
                    Toast.makeText(getActivity(),"没有网络",Toast.LENGTH_LONG).show();
                }

            }

            @Override
            public void onPullUpToRefresh(PullToRefreshBase<ListView> refreshView) {
                //判断网络状态
                if(Http.isWorkConnected(getActivity())){
                    //上拉加载
                    Http.httpAsynTask(str, new Http.CallBackString() {
                        @Override
                        public void getData(String s) {
                            //解析
                            Gson gson=new Gson();
                            JsonBean bean = gson.fromJson(s, JsonBean.class);
                            ArrayList<Datas> datas = bean.getData();
                            data.addAll(datas);
                            adapter.notifyDataSetChanged();
                            //  当列表被刷新时，调用onRefreshComplete
                            listv.onRefreshComplete();
                        }
                    });
                }else {
                    Toast.makeText(getActivity(),"没有网络",Toast.LENGTH_LONG).show();
                }

            }
        });
    }
}

fragment用到的适配器

package com.ang.lianxi.adapter;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.ang.lianxi.R;
import com.ang.lianxi.bean.Datas;
import com.nostra13.universalimageloader.core.ImageLoader;

import java.util.ArrayList;


public class MyAdapter extends BaseAdapter {
    private ArrayList<Datas> arr;
    private Context con;

    public MyAdapter(ArrayList<Datas> arr, Context con) {
        this.arr = arr;
        this.con = con;
    }

    @Override
    public int getCount() {
        return arr.size();
    }

    @Override
    public Object getItem(int i) {
        return null;
    }

    @Override
    public long getItemId(int i) {
        return 0;
    }

    @Override
    public int getViewTypeCount() {
        return 3;
    }

    @Override
    public int getItemViewType(int position) {
        return position%3;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        switch (getItemViewType(i)){
            case 0:
                ViewHolder vh;
                if(view==null){
                    view=LayoutInflater.from(con).inflate(R.layout.item_one, null);
                    vh=new ViewHolder();
                    vh.img=view.findViewById(R.id.img);
                    vh.tit=view.findViewById(R.id.tit);
                    view.setTag(vh);
                }else{
                    vh= (ViewHolder) view.getTag();
                }
                vh.tit.setText(arr.get(i).getTitle());
                ImageLoader.getInstance().displayImage(arr.get(i).getThumbnail_pic_s(),vh.img);
                break;
            case 1:
                ViewHolder1 vh1;
                if(view==null){
                    view=LayoutInflater.from(con).inflate(R.layout.item_two, null);
                    vh1=new ViewHolder1();
                    vh1.img=view.findViewById(R.id.img);
                    vh1.name=view.findViewById(R.id.name);
                    vh1.tit=view.findViewById(R.id.tit);
                    view.setTag(vh1);
                }else{
                    vh1= (ViewHolder1) view.getTag();
                }
                vh1.tit.setText(arr.get(i).getTitle());
                vh1.name.setText(arr.get(i).getAuthor_name());
                ImageLoader.getInstance().displayImage(arr.get(i).getThumbnail_pic_s(),vh1.img);
                break;
            case 2:
                ViewHolder2 vh2;
                if(view==null){
                    view=LayoutInflater.from(con).inflate(R.layout.item_three, null);
                    vh2=new ViewHolder2();
                    vh2.tit=view.findViewById(R.id.tit);
                    view.setTag(vh2);
                }else{
                    vh2= (ViewHolder2) view.getTag();
                }
                vh2.tit.setText(arr.get(i).getTitle());
                break;
        }
        return view;
    }
    static class ViewHolder{
        ImageView img;
        TextView tit;
    }
    static class ViewHolder1{
        ImageView img;
        TextView tit,name;
    }
    static class ViewHolder2{
        TextView tit;
    }
}

如果里面有CheckBox 避免和点击事件冲突

<!--android:focusable="false"避免冲突-->
    <CheckBox
        android:layout_width="0dp"
        android:layout_weight="1"
        android:layout_height="wrap_content"
        android:textSize="20sp"
        android:focusable="false"
        android:text="点击勾选"
        />

最后记住要写网络权限、ImageLoader也要注册一下

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <application
        android:name=".app.App"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>