DTM(Man)

package com.example.day8_lianxi2;

import android.app.ActivityManager;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;

import com.bawei.xlistviewlib.view.XListView;
import com.example.adapter.MyAdapter;
import com.example.bean.DataInfo;
import com.google.gson.Gson;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;

public class MainActivity extends AppCompatActivity implements XListView.IXListViewListener {

    private XListView list;
    private String api = "http://gank.io/api/data/all/20/";
    //出来就加载
    private boolean state_load = true;
    //显示上一页
    private boolean state_pull = false;
    //加载更多
    private boolean state_push = false;
    //定义页数
    private int page = 2;
    private MyAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        list = findViewById(R.id.list);
        //允许上拉加载
        list.setPullLoadEnable(true);
        list.setPullRefreshEnable(true);
        //设置回调
        list.setXListViewListener(this);
        new loadData().execute(api+page);
    }

    //显示上次刷新时间
    @Override
    public void onRefresh() {
        changeState(false,true,false);
        //请求前一页数据
        if (page > 1){
            page--;
            new loadData().execute(api+page);
        }
    }

    private void changeState(boolean b, boolean b1, boolean b2) {
        state_load = b;
        state_pull = b1;
        state_push = b2;
    }

    @Override
    public void onLoadMore() {
        changeState(false,false,true);
        page++;
        new loadData().execute(api+page);
    }

    private class loadData extends AsyncTask{

        @Override
        protected String doInBackground(String... strings) {
            try {
                URL url = new URL(strings[0]);
                HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                connection.setRequestMethod("GET");
                connection.setReadTimeout(5000);
                connection.setConnectTimeout(5000);
                if (connection.getResponseCode()==200){
                    return StringStream(connection.getInputStream());
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

        private String StringStream(InputStream inputStream) {
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            byte[] bytes = new byte[1024];
            int len = 0;
            try {
                while (( len = inputStream.read(bytes))!=-1){
                    bos.write(bytes,0,len);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return new String(bos.toByteArray());
        }

        //写解析
        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            Gson gson = new Gson();
           DataInfo dataInfo = gson.fromJson(s, DataInfo.class);
            //Log.i("aaa",s);
            if (state_load){
                adapter = new MyAdapter(dataInfo.getResults(), MainActivity.this);
                list.setAdapter(adapter);
            }else if (state_pull){//刷新上面的
                adapter.add(dataInfo.getResults());
                //停止刷新
                list.stopRefresh(true);
            }else{
                adapter.loadMore(dataInfo.getResults());
                //停止加载
                list.stopLoadMore();
            }
        }
    }
}