Android中Json数据解析，Thread+Handler ，SimpleAdapter使用小案例

1.本代码中的数据是由服务器提供。Json数据解析请参考 http://blog.csdn.net/suren__123/article/details/6938547 。

布局文件十分简单，主要用于小测试，就一份listview控件。

代码如下：

package com.sb.sbbimproject;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.ProtocolException;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

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

import android.app.Activity;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class PendingItemsNewActivity extends Activity {
protected static final String TAG ="PendingItemsNewActivity";
private String path="http://192.168.31.201:81/JK_Ser/api/Workflow/GetWorkflowList?ProjectId=2";
private   final  List<Map<String, String>> lst = new ArrayList<Map<String, String>>();
private  ListView  lv_newpending;
private SimpleAdapter   adapter;
private    Handler   handler=new Handler(){

public void handleMessage(Message msg) {
switch(msg.what){

case 1:
Log.i(TAG, "解析成功");

Log.i(TAG, lst.toString());

adapter.notifyDataSetChanged();

break;

case 2:
Log.i(TAG, "解析失败请检查网络");
break;
}
}

};

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.waite_progress_new);
lv_newpending=(ListView) findViewById(R.id.lv_newpending);
adapter=new  SimpleAdapter(this, lst, android.R.layout.simple_expandable_list_item_1, new String[]{"Name"}, new int[]{android.R.id.text1});
lv_newpending.setAdapter(adapter);

try {
getJSONObject(path);

} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

/**
* 解析json数据
* @param path
* @return
* @throws Exception

*/
public  void getJSONObject( final String path) throws Exception {

new Thread(){

public void run() {

Message msg=Message.obtain();

try {
Map<String, String> map = null;
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();// 利用HttpURLConnection对象,我们可以从网络中获取网页数据.
conn.setConnectTimeout(10 * 1000);   // 单位是毫秒，设置超时时间为5秒
conn.setRequestMethod("GET");

// HttpURLConnection是通过HTTP协议请求path路径的，所以需要设置请求方式,可以不设置，因为默认为GET
if (conn.getResponseCode() == 200) {// 判断请求码是否是200码，否则失败
InputStream is = conn.getInputStream(); // 获取输入流
byte[] data = readStream(is);   // 把输入流转换成字符数组
String json = new String(data);// 把字符数组转换成字符串

//数据形式：{"total":2,"success":true,"arrayData":[{"id":1,"name":"小猪"},{"id":2,"name":"小猫"}]}
JSONObject jsonObject=new JSONObject(json);     //返回的数据形式是一个Object类型，所以可以直接转换成一个Object
Boolean success=jsonObject.getBoolean("success");
Log.i(TAG,  " | success:" + success);   //测试数据

JSONArray jsonArray = jsonObject.getJSONArray("data");//里面有一个数组数据，可以用getJSONArray获取数组
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject item = jsonArray.getJSONObject(i); // 得到每个对象

String ID=item.getString("ID");  // 获取对象对应的值
String Name = item.getString("Name");

map = new HashMap<String, String>(); // 存放到MAP里面
map.put("ID", ID);
map.put("Name", Name);
lst.add(map);

msg.what=1;

}

}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
msg.what=2;
} catch (ProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally{

handler.sendMessage(msg);

}
}

}.start();

}
/**
* 把输入流转换成字符数组
* @param inputStream   输入流
* @return  字符数组
* @throws Exception
*/
public static byte[] readStream(InputStream inputStream) throws Exception {
ByteArrayOutputStream bout = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while ((len = inputStream.read(buffer)) != -1) {
bout.write(buffer, 0, len);
}
bout.close();
inputStream.close();
return bout.toByteArray();
}

@Override
protected void onResume() {
// TODO Auto-generated method stub

super.onResume();
}
}

说明： UI只能在主线程中进行进行修改有两种方式，一种是在Handler中进行修改，另外一种如下:

MainActivity.this.runOnUiThread(new Runnable(){

@Override
public void run() {

//	tv.setText(json);

}});

在向浏览器发送请求的时候，有时候会需要输入参数的情况，下面的代码，和上面的代码有些类似，只不过添加了两个参数：name和pwd. 如果想写一个登陆功能可参考

http://blog.csdn.net/redarmy_chen/article/details/26860769 。

/**
* 获取用户的uid
* @param path
*/

public void   getData( final String path){

new Thread(){

public void run() {

Message msg=Message.obtain();

try {
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();// 利用HttpURLConnection对象,我们可以从网络中获取网页数据.
conn.setConnectTimeout(5 * 1000);   // 单位是毫秒，设置超时时间为5秒
conn.setDoOutput(true);      //设置可以写如数据
conn.setDoInput(true);   //设置可以读出数据
conn.setRequestMethod("POST");
// 传递的数据
String Data = "name=" + URLEncoder.encode("admin", "UTF-8")
+ "&pwd=" + URLEncoder.encode("123", "UTF-8");

//获取输出流
OutputStream os = conn.getOutputStream();
os.write(Data.getBytes());
os.flush();

if (conn.getResponseCode() == 200) {// 判断请求码是否是200码，否则失败
InputStream is = conn.getInputStream(); // 获取输入流
byte[] data = readStream(is);   // 把输入流转换成字符数组
//				    String json = new String(data);// 把字符数组转换成字符串
json=new String(data);

msg.what=1;

MainActivity.this.runOnUiThread(new Runnable(){

@Override
public void run() {

tv.setText(json);

}});

}

} catch (MalformedURLException e) {
// TODO Auto-generated catch block
msg.what=2;
e.printStackTrace();
} catch (ProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally{

handler.sendMessage(msg);

}
}
}.start();

说明：readStream参照上面代码即可。在此使用runOnUiThread 进行UI更新。