public function setValueType($value_type = '') {
		$this->value_type = $value_type;
		if (!$this->getValidationRule('type')) {
			$this->addValidationRule('type', $value_type);
		}
		return $this;
	}
public function setValueType($value_type = '') {
		$this->value_type = $value_type;
		if (!$this->getValidationRule('type')) {
			$this->addValidationRule('type', $value_type);
		}
		return $this;
	}
{@inheritdoc}