private void getBefore(int id) {
   if (isLoading) {
     return;
   }
   isLoading = true;
   WebService.getInstance().asyncGet(themeURL + Config.URL_THEME_BEFORE + id, mBeforeJsonCallback);
 }
 @Override
 public void onRefresh() {
   mSwipeRefreshLayout.setRefreshing(true);
   WebService.getInstance().asyncGet(themeURL, mLatestJsonCallback);
 }