@Override
 protected Drawable doInBackground(String... urls) {
   if (mNetworkUtil.isNetworkAvailable(mContext)) {
     try {
       InputStream is = (InputStream) new URL(urls[0]).getContent();
       Drawable d = Drawable.createFromStream(is, "image");
       return d;
     } catch (Exception e) {
       e.printStackTrace();
       return mContext.getResources().getDrawable(R.drawable.ic_action_alert);
     }
   } else return mContext.getResources().getDrawable(R.drawable.ic_action_alert);
 }
 @Override
 protected Integer doInBackground(String... params) {
   if (mNetworkUtil.isNetworkAvailable(mContext)) {
     if (params[0].trim().length() > 0 && params[1].trim().length() > 0) {
       HttpClient httpclient = new DefaultHttpClient();
       HttpPost httppost = new HttpPost(AUTHENTICATION_URL);
       try {
         List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
         nameValuePairs.add(new BasicNameValuePair(TAG_USERNAME, params[0].trim()));
         nameValuePairs.add(new BasicNameValuePair(TAG_PASSWORD, params[1].trim()));
         httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
         HttpResponse response = httpclient.execute(httppost);
         if (response.toString().equals("")) return SUCCESS;
         else return ERROR_WRONG_CREDENTIALS;
       } catch (Exception e) {
         e.printStackTrace();
         return ERROR_EXCEPTION;
       }
     } else return ERROR_WRONG_INPUT;
   } else return ERROR_NO_CONNECTION;
 }