得到天气信息在wifi上工作但不在3g（Android）

Question

我正在尝试从googles API解析天气信息，当WIFI连接时它可以正常工作，但是当手机通过3G连接到互联网时却没有。

import java.net.URL;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;


import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.StrictMode;
import android.widget.Toast;

public class GetWeather2 extends Activity{


static final String baseURL = "http://www.google.com/ig/api?weather=";

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.getweather2);

    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
            .detectAll().penaltyLog().build();
    StrictMode.setThreadPolicy(policy); 


    String c = "mycity";

    StringBuilder URL = new StringBuilder(baseURL);
    URL.append(c);
    String fullURL = URL.toString();

    try{
        URL website = new URL(fullURL);
        //getting xmlreader to parse data
        SAXParserFactory spf = SAXParserFactory.newInstance();
        SAXParser sp = spf.newSAXParser();
        XMLReader xr = sp.getXMLReader();

        HandlingXMLStuff doingWork = new HandlingXMLStuff();
        xr.setContentHandler(doingWork);
        xr.parse(new InputSource(website.openStream()));
        String[] weatherInfo = new String[] {};
        weatherInfo = doingWork.getInformation();
        information[5] = weatherInfo[0];
        information[3] = weatherInfo[1];
        //tv.setText(information);
        Intent i = new Intent("blabla");
        i.putExtra("information", information);
        startActivity(i);
        finish();

    }catch (Exception e){
        Toast.makeText(this, "error weather", Toast.LENGTH_SHORT).show();
        Intent i = new Intent("com.blaabla");
        i.putExtra("information", information);
        startActivity(i);
        finish();
    }
}

}

（为了便于阅读，我缩小了代码）

我已经检查了手机网络浏览器中的完整网址，并且XML文档在使用wifi时看起来很好但是当它关​​闭时，页面显示它不可用。