Android平台上的Goodle Reader API开发问题

我想利用Goole Reader API来获得用户订阅的列表。
根据Goole Reader API操作。
第一步POST，将用户名和密码发送给https://www.google.com/accounts/ClientLogin没有问题，正确得到SID。
第二部利用SID作为Cookie向http://www.google.com/reader/atom/发起GET请求却遇到的问题，不能得到想要的XML文件，只能得到一个未登录的HTML页面文件，我明明在第一步登录了啊。

附代码（为了保护隐私，其中用户名和密码用*表示）：

package hello.android;

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

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;

import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;

import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;

import android.app.Activity;
import android.os.Bundle;
import android.widget.EditText;
import android.widget.TextView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class HelloAndroid extends Activity {

Button btn;
TextView tv;
EditText et;
OnClickListener btnClick;
String strResult;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        tv = (TextView)this.findViewById(R.id.textview1);
        if (tv == null) {
         return;
        }

        btn = (Button)this.findViewById(R.id.button1);
        if (btn == null)
         return;

        et = (EditText)this.findViewById(R.id.edittext1);

        if (et == null)
         return;

        btnClick = new OnClickListener() {
         @Override
         public void onClick(View v) {
         tv.setText("test");
         googleReader();
         }
        };

        btn.setOnClickListener(btnClick);
    }

    public boolean httpPost(String url, List<NameValuePair> params) {
     boolean ret = true;
     HttpPost httpRequest = new HttpPost(url);

     try {
     httpRequest.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
     HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequest);
     if (httpResponse.getStatusLine().getStatusCode() == 200) {
     strResult = EntityUtils.toString(httpResponse.getEntity());
     et.setText(strResult);
     }
     else {
     ret = false;
     et.setText("Error Response: " + httpResponse.getStatusLine().toString());
     }
     }
     catch (ClientProtocolException e) {
     ret = false;
et.setText(e.getMessage().toString());
}
catch (IOException e) {
ret = false;
et.setText(e.getMessage().toString());
}
catch (Exception e) {
ret = false;
et.setText(e.getMessage().toString());
}

     return ret;
    }

    public boolean httpGet(String url, List<NameValuePair> params) {
     boolean ret = true;
     HttpGet httpRequest = new HttpGet(url);

     for (int i = 0; i < params.size(); ++i) {
     httpRequest.addHeader(params.get(i).getName(), params.get(i).getValue());
     }

     try {
     HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequest);
     if (httpResponse.getStatusLine().getStatusCode() == 200) {
     String strResult = EntityUtils.toString(httpResponse.getEntity());
     et.setText(strResult);
     }
     else {
     et.setText("Error Response: " + httpResponse.getStatusLine().toString());
     }
     }
     catch (ClientProtocolException e) {
     ret = false;
et.setText(e.getMessage().toString());
}
catch (IOException e) {
ret = false;
et.setText(e.getMessage().toString());
}
catch (Exception e) {
ret = false;
et.setText(e.getMessage().toString());
}

     return ret;
    }

    public boolean googleReader() {
     String url = "https://www.google.com/accounts/ClientLogin";
     List<NameValuePair> params = new ArrayList<NameValuePair>();
     params.add(new BasicNameValuePair("service", "reader"));
     params.add(new BasicNameValuePair("Email", "********@gmail.com"));
     params.add(new BasicNameValuePair("Passwd", "********"));
     params.add(new BasicNameValuePair("continue", "http://www.google.com/"));

     // 发送POST请求，获得一串文本
     if (!httpPost(url, params))
     return false;

     // 解析SID
     int startSID = strResult.indexOf("SID=");
     if (startSID == -1)
     return false;
     int endSID = strResult.indexOf("\n", startSID);
     if (endSID == -1)
     return false;

     // 得到SID
     String strSID = strResult.substring(startSID + 4, endSID);

     url = "http://www.google.com/reader/atom/";
     params.clear();

     // 构造Cookies
     String strCookies = "name=";
     strCookies += (strSID + "; ");
     strCookies += "domain=.google.com; ";
     strCookies += "path=/; ";
     strCookies += "expires=1600000000";
     params.add(new BasicNameValuePair("Cookie", strCookies));

     // 发送GET请求
     if (!httpGet(url, params))
     return false;

     return true;
    }
}

补充：移动开发 ,  Android