Android网络请求，获取数据，解析数据Demo

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添加依赖

build.gradle

dependencies {  
    compile 'com.google.code.gson:gson:2.4'  
}  

右上角Sync Now

在AndroidManifest.xml中添加网络访问权限

<uses-permission android:name="android.permission.INTERNET"/>  

主页面布局

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>  
<LinearLayout  
    xmlns:android="http://schemas.android.com/apk/res/android"  
    xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main"  
    android:layout_width="match_parent" android:layout_height="match_parent"  
    android:orientation="vertical"  
    tools:context="com.example.httpdemo.MainActivity">  
    <TextView  
        android:id="@+id/header"  
        android:layout_width="match_parent"  
        android:layout_height="48dp"  
        android:text="慕课"  
        android:textSize="28sp"  
        android:gravity="center"  
        android:textColor="#ffffff"  
        android:background="#3f51b5"  
        android:paddingRight="15dp"/>  
    <ImageView  
        android:id="@+id/banner"  
        android:layout_width="match_parent"  
        android:layout_height="wrap_content"  
        android:scaleType="fitXY"/>  
    <ListView  
        android:id="@+id/essay_view"  
        android:layout_width="match_parent"  
        android:layout_height="match_parent"></ListView>  
</LinearLayout>  

被跳转页面布局

activity_detail.xml

<?xml version="1.0" encoding="utf-8"?>  
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    xmlns:tools="http://schemas.android.com/tools"  
    android:id="@+id/content_detail"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    tools:showIn="@layout/activity_detail"  
    android:orientation="vertical" >  

    <TextView  
        android:id="@+id/name"  
        android:layout_width="match_parent"  
        android:layout_height="wrap_content"  
        android:textSize="24sp"  
        android:gravity="center"  
        android:layout_marginTop="15dp" />  

    <TextView  
        android:id="@+id/author"  
        android:layout_width="match_parent"  
        android:layout_height="wrap_content"  
        android:textSize="20sp"  
        android:gravity="right"  
        android:paddingRight="10dp"  
        android:layout_marginTop="15dp"/>  

    <TextView  
        android:id="@+id/content"  
        android:layout_width="match_parent"  
        android:layout_height="match_parent"  
        android:layout_margin="8dp"  
        android:layout_marginTop="15dp"  
        android:layout_weight="1"  
        android:lineSpacingMultiplier="1.5"  
        android:textSize="20sp" />  
</LinearLayout>  

数据实体类

Essay.java

package com.administrator.hellodemo;  



public class Essay {  
    private String title;  
    private String author;  
    private String content;  

    public Essay(String title, String author, String content) {  
        this.title = title;  
        this.author = author;  
        this.content = content;  
    }  

    public String getTitle() {  
        return title;  
    }  

    public void setTitle(String title) {  
        this.title = title;  
    }  

    public String getAuthor() {  
        return author;  
    }  

    public void setAuthor(String author) {  
        this.author = author;  
    }  

    public String getContent() {  
        return content;  
    }  

    public void setContent(String content) {  
        this.content = content;  
    }  
}  

主页面Java代码

MainActivity.java

package com.administrator.hellodemo;  

import android.content.Intent;  
import android.support.v7.app.AppCompatActivity;  
import android.os.Bundle;  
import android.view.View;  

public class MainActivity extends AppCompatActivity {  

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

    private void initView() {  
        findViewById(R.id.header).setOnClickListener(new View.OnClickListener() {  
            @Override  
            public void onClick(View v) {  
                startActivity(new Intent(MainActivity.this,DetailActivity.class));  
            }  
        });  
    }  
}  

被跳转页Java代码

package com.administrator.hellodemo;  

import android.app.Activity;  
import android.content.Intent;  
import android.os.Handler;  
import android.os.Message;  
import android.os.Bundle;  
import android.util.Log;  
import android.widget.TextView;  

import com.google.gson.Gson;  

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

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

public class DetailActivity extends Activity {  
    private TextView nameView,authorView,contentView;  
    private int id;  
    private Handler handler = new Handler(){  
        @Override  

        public void handleMessage(Message msg) {  
            super.handleMessage(msg);  
            Essay e = (Essay) msg.obj;  
            nameView.setText(e.getTitle());  
            authorView.setText(e.getAuthor());  
            contentView.setText(e.getContent());  

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

        Intent it = getIntent();  
        id = it.getIntExtra("essay",1);  
        initView();  
        initData();  
    }  

    public void initView(){  
        nameView = (TextView) findViewById(R.id.name);  
        authorView = (TextView) findViewById(R.id.author);  
        contentView = (TextView) findViewById(R.id.content);  
    }  

    public void initData(){  
        //HttpUrlConnection  
        /** 
         * 1.实例化一个url对象 
         * 2.获取HttpUrlConnection对象 
         * 3.设置请求连接属性 
         * 4.获取响应码，判断是否连接成功 
         * 5.读取输入流并解析 
         */  
        //参数：你要访问的接口地址  
        new Thread(){  
            @Override  
            public void run() {  
                try {  
                    URL url = new URL("http://www.imooc.com/api/teacher?type=3&cid="+id );  
                    HttpURLConnection coon = (HttpURLConnection) url.openConnection();  
                    coon.setRequestMethod("GET");  
                    coon.setReadTimeout(6000);  
                    //获取响应码  
                    if(coon.getResponseCode() == 200){  
                        //获取输入流  
                        InputStream in = coon.getInputStream();  
                        byte[] b = new byte[1024*512];  
                        int len = 0;  
                        //建立缓存流，保存所读取的字节数组  
                        ByteArrayOutputStream baos = new ByteArrayOutputStream();  
                        while ((len = in.read(b)) > -1){  
                            baos.write(b,0,len);  
                        }  
                        String msg = baos.toString();  
                        Log.e("TAG",msg);  
                        //JSON数据的解析：  
                        JSONObject obj = new JSONObject(msg);  

                        //HashMap map = null;  
                        //map.get("age")  
                        int status = obj.getInt("status");  
                        String msg2 = obj.getString("msg");  
                        Log.e("TAG",status + "   " + msg2);  

                        //1.创建Gson对象  
                        Gson gson = new Gson();  
                        //参数1：满足json对象格式的字符串  
                        String data = obj.getString("data");  
                        Essay e = gson.fromJson(data,Essay.class);  



                        /*JSONObject data = obj.getJSONObject("data"); 
                        String title = data.getString("title"); 
                        String author = data.getString("author"); 
                        String content = data.getString("content"); 
                        Log.e("TAG","标题：" + title + "，作者：" + author + "，内容：" + content);*/  
                        //将操作权交还给主线程  

                        Message message = handler.obtainMessage();  
                        //Essay e = new Essay(title,author,content);  
                        message.obj =e;  

                        //调用此方法，则会触发主线程中Handle对象里覆盖了的handleMessage方法  
                        handler.sendMessage(message);  

                    }  
                } catch (MalformedURLException e) {  
                    e.printStackTrace();  
                } catch (IOException e) {  
                    e.printStackTrace();  
                } catch (JSONException e) {  
                    e.printStackTrace();  
                }  
            }  
        }.start();  



    }  


}