xlistview的使用（上拉下拉）

需要导入XListView-Android-master.zip压缩包中的需要用到类，布局文件以及drawable中的图片，还有values中的strings文件中的四个带汉字的四行代码

XListView-Android-master.zip：这个放在项目实战——》代码——》09——》ziliao中

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:layout_width="match_parent"
    android:layout_height="match_parent">

    <news1510a.bawei.com.a09_xlistview_demo.view.XListView
        android:id="@+id/x_list_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    </news1510a.bawei.com.a09_xlistview_demo.view.XListView>
</RelativeLayout>
————————————》activity代码

package news1510a.bawei.com.a09_xlistview_demo;

import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import com.google.gson.Gson;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import news1510a.bawei.com.a09_xlistview_demo.view.XListView;

/**
 * XlIstView在github上开源,,,地址:https://github.com/Maxwin-z/XListView-Android
 *
 * XlistView使用参考博客地址:
 *
 * 1.下载gitHub上XlistView上的压缩包
 * 2.复制view包下的三个类,,,,,注意导包的问题
 * 3.赋值layout下面的footer布局和header的布局
 * 4.赋值string下面的字段值
 *
 *
 * 支持下拉刷新和上拉加载的操作
 *  1.设置上拉还是下拉,还是两个都使用
 *  2.设置刷新的监听事件....在监听事件里面去加载数据,然后刷新适配器的操作
 *
 *  这里使用接口地址是:http://www.yulin520.com/a2a/impressApi/news/mergeList?pageSize=10&page=1
 *
 *  下拉刷新的时候,添加到集合的最前边
 *  上拉加载的时候,添加到集合的后边
 *
 *  -------------------
 *  1.加上图片.....使用imageLoader,,,,图片缓存的位置在sd卡根目录下的image文件夹
 *  2.加上多条目加载.....根据条目的奇偶数显示不同的视图
 *
 */
public class MainActivity extends AppCompatActivity implements XListView.IXListViewListener {

    private XListView xListView;

    //定义一个大的集合,,,装当前页面所有的数据
    private List<DataDataBean.DataBean> list = new ArrayList<>();
    private MyAdapter myAdapter;

    //定义一个int值记录第几页
    private int page_num = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        xListView = (XListView) findViewById(R.id.x_list_view);

        //设置支持上拉还是下拉
        xListView.setPullRefreshEnable(true);//支持下拉刷新
        xListView.setPullLoadEnable(true);//支持上拉加载更多
        xListView.setXListViewListener(this);//设置xlistView的监听事件


        getDataFromNet();
    }

    private void getDataFromNet() {
        AsyncTask<Void, Void, String> asyncTask = new AsyncTask<Void, Void, String>() {
            @Override
            protected String doInBackground(Void... voids) {

                String path = "http://www.yulin520.com/a2a/impressApi/news/mergeList?pageSize=10&page=1";
                try {
                    URL url = new URL(path);

                    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                    //设置
                    connection.setRequestMethod("GET");
                    connection.setReadTimeout(5000);
                    connection.setConnectTimeout(5000);

                    //获取
                    int responseCode = connection.getResponseCode();
                    if (responseCode == 200){
                        InputStream inputStream = connection.getInputStream();

                        String json = streamToString(inputStream,"utf-8");

                        return json;
                    }

                } catch (Exception e) {
                    e.printStackTrace();
                }

                return null;
            }

            @Override
            protected void onPostExecute(String s) {
                Gson gson = new Gson();

                DataDataBean dataDataBean = gson.fromJson(s, DataDataBean.class);

                //将解析到的集合数据添加到上面的大集合中
                list.addAll(dataDataBean.getData());

                //设置适配器...
                setAdapter();

                //上拉加载完成....停止加载
                xListView.stopLoadMore();
            }
        };

        asyncTask.execute();
    }

    /**
     * 设置适配器
     */
    private void setAdapter() {
        if (myAdapter == null){

            myAdapter = new MyAdapter(MainActivity.this, list);
            xListView.setAdapter(myAdapter);
        }else {
            myAdapter.notifyDataSetChanged();
        }
    }

    /**
     * 这是下拉刷新的时候自动调用的方法
     *
     * 例如,,,下拉刷新的时候我们让他请求下一页的内容
     */
    @Override
    public void onRefresh() {
        page_num ++;

        AsyncTask<Void, Void, String> asyncTask = new AsyncTask<Void, Void, String>() {
            @Override
            protected String doInBackground(Void... voids) {

                String path = "http://www.yulin520.com/a2a/impressApi/news/mergeList?pageSize=10&page="+page_num;
                try {
                    URL url = new URL(path);

                    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                    //设置
                    connection.setRequestMethod("GET");
                    connection.setReadTimeout(5000);
                    connection.setConnectTimeout(5000);

                    //获取
                    int responseCode = connection.getResponseCode();
                    if (responseCode == 200){
                        InputStream inputStream = connection.getInputStream();

                        String json = streamToString(inputStream,"utf-8");

                        return json;
                    }

                } catch (Exception e) {
                    e.printStackTrace();
                }

                return null;
            }

            @Override
            protected void onPostExecute(String s) {
                Gson gson = new Gson();

                DataDataBean dataDataBean = gson.fromJson(s, DataDataBean.class);

                //下拉刷新的数据需要添加在大集合的最前边
                list.addAll(0,dataDataBean.getData());

                //设置适配器...
                setAdapter();

                //...............设置完数据之后刷新需要停止
                xListView.stopRefresh();//停止刷新

                //System.currentTimeMillis()....当前时间的long类型的值
                Date date = new Date(System.currentTimeMillis());
                //格式化....yyyy-MM-dd HH:mm
                SimpleDateFormat simpleDateFormat = new SimpleDateFormat("HH:mm");

                //设置本次刷新的时间
                xListView.setRefreshTime(simpleDateFormat.format(date));
            }
        };

        asyncTask.execute();
    }

    /**
     * 这是上拉加载的时候调用的方法
     *
     * 上拉加载更多......例如:让他请求第一页数据
     */
    @Override
    public void onLoadMore() {

        //再次调用
        getDataFromNet();
    }


    private String streamToString(InputStream inputStream,String charset) {
        try {
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream,charset);

            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
            String s = null;
            StringBuilder builder = new StringBuilder();
            while ((s = bufferedReader.readLine()) != null){
                builder.append(s);
            }

            bufferedReader.close();
            return builder.toString();

        } catch (Exception e) {
            e.printStackTrace();
        }

        return  null;
    }
}

——————————————设置适配器myAdapter

package news1510a.bawei.com.a09_xlistview_demo;

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 java.util.List;

/**
 * @author Dash
 * @date 2017/10/11
 * @description:
 */
public class MyAdapter extends BaseAdapter{
    Context context;
    List<DataDataBean.DataBean> list;

    public MyAdapter(Context context, List<DataDataBean.DataBean> list) {
        this.context = context;
        this.list = list;
    }

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

    /**
     * 获取当前条目展示的内容
     * @param i
     * @return
     */
    @Override
    public Object getItem(int i) {
        return list.get(i);
    }

    /**
     * 获取当前条目的id,,,,只要唯一就可以
     * @param i
     * @return
     */
    @Override
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        ViewHolder holder;
        if (view == null){
            view = View.inflate(context,R.layout.item_layout,null);
            holder = new ViewHolder();

            holder.textView = view.findViewById(R.id.text_title);

            view.setTag(holder);
        }else {
            holder = (ViewHolder) view.getTag();
        }

        holder.textView.setText(list.get(i).getTitle());

        return view;
    }

    private class ViewHolder{
        ImageView imageView;
        TextView textView;
    }
}

————————————》myadapter的布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:padding="10dp"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/image_view"
        android:layout_width="100dp"
        android:layout_height="100dp" />

    <TextView
        android:id="@+id/text_title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>