/**
  * Validate the form
  */
 protected function validateForm()
 {
     if ($this->frm->isSubmitted()) {
         $this->frm->cleanupFields();
         // validation
         $fields = $this->frm->getFields();
         $fields['username']->isFilled(Language::err('FieldIsRequired'));
         if ($this->frm->isCorrect()) {
             $item['id'] = $this->id;
             $item['username'] = $fields['username']->getValue();
             // lookup user id
             $userObj = Helper::searchUser($item['username']);
             if (isset($userObj->data)) {
                 $userId = $userObj->data[0]->id;
                 $item['user_id'] = $userId;
             } else {
                 $this->redirect(Model::createURLForAction('Index') . '&error=api_error');
             }
             BackendInstagramModel::update($item);
             $item['id'] = $this->id;
             Model::triggerEvent($this->getModule(), 'after_edit', $item);
             $this->redirect(Model::createURLForAction('Index') . '&report=edited&highlight=row-' . $item['id']);
         }
     }
 }