JsonUtils

Posted 2020-08-12

package com.example.administrator.mytest.Utils;

import android.os.Handler;
import android.os.Message;
import android.util.Log;

import com.example.administrator.mytest.Bean.Data;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

/**
 * Created by Administrator on 2016/9/30.
 */
public class JsonUtils {
    private List<Data>[] msg_List;
    private CallBackListener listener;
    public JsonUtils(){

    }
    //通知谁更新，得告诉我(外部关注加载数据类通过此方法注册)
    public JsonUtils(CallBackListener listener){
       this.listener=listener;
    }
    //明确访问的路径http://news.ifeng.com/,获取网络数据
    //返回的数据格式:[[{},{}],[{},{}],[{},{},{}],[{}]]
    public void getResult(){
        new Thread(
                new Runnable() {
                    @Override
                    public void run() {
                        //1.需要创建一个OkHttpClient对象，一个APP里面最好实例化一个对象
                        OkHttpClient client=new OkHttpClient();
                        //2.新建一个请求
                        final Request request=new Request.Builder().url("http://news.ifeng.com/").build();
                        //3.执行请求，获得响应数据
                        Call call=client.newCall(request);
                        //4.加入调度，执行回调处理
                        call.enqueue(new Callback() {
                            @Override
                            public void onFailure(Call call, IOException e) {
                                Log.i("json","onResponse:-----failure");
                            }
                            @Override
                            public void onResponse(Call call, Response response) throws IOException {
                                Log.i("json","onResponse:----->"+response.body().string());
                                if (response.isSuccessful()){
                                    String str=response.body().string();
                                    Message msg=new Message();
                                    msg.obj=str;
                                    msg.arg1=0x1;
                                    mHandler.sendMessage(msg);
                                }
                            }
                        });
                    }
                }
        ).start();
    }
    private Handler mHandler=new Handler(){
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            if (msg.arg1==0x1){
                //处理返回的字符串
                getJson(msg.obj.toString());
            }
        }
    };

    //截取返回数据中的JSON格式数据
    public void getJson(String msg) {
        String json=null;
        if (msg!=null){
            //indexof不包含前面的字符,所以后面的字符要加3个长度
            json=msg.substring(msg.indexOf("[[{"),msg.indexOf("}]]")+3);
            Log.i("","getjson:----->"+json);
        }
        initMessage(json);
    }

    //解析JSON字符串得到有效数据
    public void initMessage(String json){
        try {
            JSONArray array=new JSONArray(json);
            msg_List=new ArrayList[array.length()];
            for (int i=0;i<array.length();i++){
               JSONArray arr= array.getJSONArray(i);
                msg_List[i]=new ArrayList<>();
                for (int j=0;j<arr.length();j++){
                    JSONObject obj=arr.getJSONObject(j);
                    Data data=new Data();
                    data.setThumbnail( obj.getString("thumbnail"));
                    data.setTitle(obj.getString("title"));
                    data.setUrl(obj.getString("url"));
                    msg_List[i].add(data);

                }
            }

        } catch (JSONException e) {
            e.printStackTrace();
        }
        //通知注册进来的类去更新界面
        listener.upData(msg_List);
    }
    //关注着数据加载的父类接口
    public interface  CallBackListener{
        void upData(List<Data>[] msg_List);
    }
}