app开发历程————Android程序解析服务器端的JSON格式数据，显示在界面上

上一篇文章写的是服务器端利用Servlet 返回JSON字符串，本文主要是利用android客户端访问服务器端链接，解析JSON格式数据，放到相应的位置上。

首先，android程序的布局文件main.xml

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:paddingBottom="@dimen/activity_vertical_margin"
 6     android:paddingLeft="@dimen/activity_horizontal_margin"
 7     android:paddingRight="@dimen/activity_horizontal_margin"
 8     android:paddingTop="@dimen/activity_vertical_margin"
 9     tools:context=".MainActivity" 
10     android:orientation="vertical">
11 
12     <TextView
13         android:id="@+id/textView"
14         android:layout_width="wrap_content"
15         android:layout_height="wrap_content"
16         />
17 
18 </LinearLayout>

MainActivity.java

  1 package com.practice;
  2 
  3 import java.io.BufferedReader;
  4 import java.io.InputStreamReader;
  5 
  6 import org.apache.http.HttpEntity;
  7 import org.apache.http.HttpResponse;
  8 import org.apache.http.client.HttpClient;
  9 import org.apache.http.client.methods.HttpGet;
 10 import org.apache.http.impl.client.DefaultHttpClient;
 11 import org.apache.http.params.HttpConnectionParams;
 12 import org.apache.http.params.HttpParams;
 13 import org.json.JSONArray;
 14 import org.json.JSONObject;
 15 
 16 import android.os.Bundle;
 17 import android.app.Activity;
 18 import android.util.Log;
 19 import android.view.Menu;
 20 import android.widget.TextView;
 21 
 22 public class MainActivity extends Activity {
 23 
 24     @Override
 25     protected void onCreate(Bundle savedInstanceState) {
 26         super.onCreate(savedInstanceState);
 27         setContentView(R.layout.main);
 28         Log.v("111111111", "1111111111111111");
 29         
 30         
 31         
 32         try{
 33             StringBuffer sb=new StringBuffer();
 34             String url="http://192.168.0.251:8080/ServletTest/test";
 35             String body=getContent(url);
 36             Log.v("222222", body);
 37             JSONArray array=new JSONArray(body);
 38             //JSONObject ty=new JSONObject(body);
 39             for(int i=0;i<array.length();i++){
 40                 
 41                 JSONObject obj=array.getJSONObject(i);
 42                 sb.append("id:").append(obj.getInt("id")).append("\t");
 43                 sb.append("name:").append(obj.getString("name")).append("\t");
 44                 sb.append("gender:").append(obj.getString("gender")).append("\t\n");
 45                 sb.append("email:").append(obj.getString("email")).append("\t");
 46                 sb.append("----------------------\n");
 47             
 48             }
 49             Log.v("333333333333", sb.toString());
 50             TextView textView =(TextView) findViewById(R.id.textView);
 51             textView.setText(sb.toString());
 52             
 53             
 54         
 55         }
 56         catch(Exception e)
 57         {
 58             
 59             Log.v("11111111111", e.toString());
 60             Log.v("11111111111", "msg");
 61         }
 62         
 63     }
 64     
 65     
 66     private String getContent(String url) throws Exception{
 67         
 68         
 69         StringBuilder sb=new StringBuilder();
 70         HttpClient client=new DefaultHttpClient();
 71         HttpParams httpParams=client.getParams();
 72         
 73         HttpConnectionParams.setConnectionTimeout(httpParams, 3000);
 74         HttpConnectionParams.setSoTimeout(httpParams, 5000);
 75         
 76         HttpResponse response =client.execute(new HttpGet(url));
 77         HttpEntity entity =response.getEntity();
 78         
 79         if(entity!=null){
 80             BufferedReader reader=new BufferedReader(new InputStreamReader(entity.getContent()));
 81             String line =null;
 82             while((line=reader.readLine())!= null){
 83                 sb.append(line+"\n");
 84             }
 85             reader.close();
 86             
 87         }
 88         return sb.toString();
 89         
 90         
 91     }
 92     
 93 
 94     @Override
 95     public boolean onCreateOptionsMenu(Menu menu) {
 96         // Inflate the menu; this adds items to the action bar if it is present.
 97         getMenuInflater().inflate(R.menu.main, menu);
 98         return true;
 99     }
100 
101 }