xlistview

package com.example.myxlistviewdemo;

import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import com.google.gson.Gson;
import com.limxing.xlistview.view.XListView;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;
import java.util.List;

public class MainActivity extends AppCompatActivity implements XListView.IXListViewListener {

    private static final String TAG = "MainActivity";
    private XListView xLV;
    private int index = 1;
    private MyBaseAdapter adapter;
    //定义个标识值 默认是false
    private boolean flag;


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


        //找控件
        xLV = (XListView) findViewById(R.id.xLv);
        xLV.setPullLoadEnable(true);
        xLV.setXListViewListener(this);
        //设置适配器
        //xLV.setAdapter(new MyBaseAdapter());

        getData("http://apis.juhe.cn/cook/query.php",index+"",10+"");

    }


    private void getData(String path,String pn,String rn){




        new AsyncTask<String,Void,String>(){


            @Override
            protected void onPostExecute(String s) {
                super.onPostExecute(s);

                if(s == null)
                    return;

                //解析
                Gson gson = new Gson();
                MenuInfo menuInfo = gson.fromJson(s,MenuInfo.class);

                List<MenuInfo.ResultBean.DataBean> data = menuInfo.getResult().getData();


                if(adapter == null){
                    adapter = new MyBaseAdapter(data);
                    xLV.setAdapter(adapter);
                }else{

                    adapter.loadMore(data,flag);
                    adapter.notifyDataSetChanged();

                }




            }

            @Override
            protected String doInBackground(String... params) {

                try {
                    //请求接口地址
                    String path = params[0];
                    //取出的是索引页  默认 1 开始
                    String pn = params[1];
                    //指定一次给我返回多少条数据
                    String rn = params[2];
                    URL url = new URL(path);
                    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                    connection.setRequestMethod("POST");
                    connection.setConnectTimeout(5000);
                    connection.setReadTimeout(5000);


                    //post请求
                    OutputStream os = connection.getOutputStream();
                    os.write(("key=ff00d7339861c7fd7d5b54b16b76422a&menu="+
                            URLEncoder.encode("秘制红烧肉","utf-8")+"&pn="+pn+"&rn="+rn).getBytes());
                    os.flush();


                    int code = connection.getResponseCode();

                    if(code == 200){
                        InputStream is = connection.getInputStream();
                        return StreamTools.readFromNetWork(is);
                    }

                } catch (Exception e) {
                    e.printStackTrace();
                }
                return null;
            }
        }.execute(path,pn,rn);


    }

    //当下拉刷新的时候，会执行
    @Override
    public void onRefresh() {

        Log.e(TAG, "onRefresh: 刷新" );
        ++index;
        getData("http://apis.juhe.cn/cook/query.php",index+"",10+"");

        flag = true;

        //刷新成功之后，将下拉刷新进度回弹
        xLV.stopRefresh(true);


    }

    //当上拉加载更多的是后，会被执行
    @Override
    public void onLoadMore() {

        Log.e(TAG, "onLoadMore: 加载更多");
        ++index; //1,2,3
        getData("http://apis.juhe.cn/cook/query.php",index+"",10+"");

        flag = false;
        //停止加载更多
        xLV.stopLoadMore();

        
    }


    class MyBaseAdapter extends BaseAdapter{

        private  List<MenuInfo.ResultBean.DataBean> data;
        public MyBaseAdapter( List<MenuInfo.ResultBean.DataBean> data){
            this.data = data;
        }

        /**
         * 加载更多
         */
        public void loadMore(List<MenuInfo.ResultBean.DataBean> datas,boolean flag){

            //新闻为例，数据要添加到最前面
            for (MenuInfo.ResultBean.DataBean bean : datas) {
                //flag -> true 添加到卡面  false ->添加到末尾
                if(flag) {
                    //将数据添加到最前面
                    data.add(0, bean);
                }else{
                    //默认将数据添加到末尾
                    data.add(bean);
                }
            }

        }


        @Override
        public int getCount() {
            return data != null ? data.size() : 0;
        }

        @Override
        public Object getItem(int position) {
            return data.get(position);
        }

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

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {

            TextView textView = new TextView(MainActivity.this);
            textView.setHeight(100);
            textView.setText(data.get(position).getTags());

            return textView;
        }
    }





}