httpwebreques-Android: Http request 不能在 4.0上運行

Android: Http request 不能在 4.0上運行

我在 2.2 和 2.3.3 上運行這段代碼可以運行，但是在4.0上崩潰。是不是http請求的問題，大家的意見呢？

public class Rezultat extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity);

    //http post
    InputStream is=null;
    try{

            String url="http://google.com";
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost(url);
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();
            is = entity.getContent();
    }catch(Exception e){
            Log.e("log_tag", "Error in http connection "+e.toString());
    }
    //convert response to string
    try{
            BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                    sb.append(line + "\n");
            }
            is.close();
            result=sb.toString();
    }catch(Exception e){
            Log.e("log_tag", "Error converting result "+e.toString());
    }

最佳回答：

private class DownloadFromUrlTask extends AsyncTask<String, Void, Bitmap> {

    protected void onPreExecute() {
        mDialog = ProgressDialog.show(ChartActivity.this,"Please wait...", "Retrieving data ...", true);
    }

    protected String doInBackground(String... urls) {
        //All your network stuff here.
        return result
    }
}