/** * @param string $subtitle * @return null */ public function setSubtitle($subtitle) { if (!isset($this->loadedFields['subtitle'])) { $this->loadProperties(); } $oldValue = null; if (array_key_exists('subtitle', $this->loadedValues)) { $oldValue = $this->loadedValues['subtitle']; } if ($oldValue === $subtitle) { $this->subtitle = $subtitle; return; } return parent::setSubtitle($subtitle); }