问如何在android中显示一个进度条，同时等待收到短信5分钟？

EN

public class GetSMS extends Activity {
   ...
   ...
   private boolean progressDialogFlag;
   private ProgressDialog progressDialog;
   ...
   ...
   new SMSReceiver().execute();
}

public class SMSReceiver extends AsyncTask<Void, Integer, Void> {
    protected void onPreExecute() {
        // start a progressdialog box
        super.onPreExecute();
        progressDialogFlag = true;
        progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        progressDialog.setMessage("Waiting to Receive SMS...");
        progressDialog.setCancelable(false);
        progressDialog.show();

    }

    protected void onProgressUpdate(Integer... progress) {
        super.onProgressUpdate(progress);
        if (progressDialogFlag == true) {
            progressDialog.setProgress(progress[0]);
        }
        if (progress[0] == 100 || progressDialogFlag == false) {
            progressDialog.dismiss();
        }
    }

    protected void onPostExecute(Void result) {

    }

    @Override
    protected Void doInBackground(Void... params) {
        int interval = 2;
        int totalDuration = 5 * 60 * 1000; // 5 min
        int sleepPeriod = (totalDuration / 100) * interval;
        for (int i = 2; i <= 100; i += 2) {
            publishProgress(i);
            try {
                Thread.sleep(sleepPeriod);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        return null;
    }
}

smsReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
              progressdialog = false;
   }
}