/**
  * Validate the form
  */
 private function validateForm()
 {
     if ($this->frm->isSubmitted()) {
         // cleanup the submitted fields, ignore fields that were added by hackers
         $this->frm->cleanupFields();
         // validate fields
         $this->frm->getField('title')->isFilled(BL::err('TitleIsRequired'));
         // no errors?
         if ($this->frm->isCorrect()) {
             // build item
             $item['title'] = $this->frm->getField('title')->getValue();
             $item['language'] = BL::getWorkingLanguage();
             $item['publish_on'] = BackendModel::getUTCDate('Y-m-d H:i:s');
             $item['hidden'] = $this->frm->getField('hidden')->getValue();
             // get the highest sequence available
             $item['sequence'] = BackendGalleriaModel::getMaximumCategorySequence() + 1;
             // insert the item
             $item['id'] = BackendGalleriaModel::insertCategory($item);
             // trigger event
             BackendModel::triggerEvent($this->getModule(), 'after_add_category', array('item' => $item));
             // everything is saved, so redirect to the overview
             $this->redirect(BackendModel::createURLForAction('categories') . '&report=added-category&var=' . urlencode($item['title']) . '&highlight=row-' . $item['id']);
         }
     }
 }