SubButton::isActive

public function isActive()
{
	$state = $this->getSplitButton()->getState();
	if ($state === State::ACTIVE)
	{
		return true;
	}

	if ($this->isMainButton())
	{
		return $state === State::MAIN_ACTIVE;
	}
	else
	{
		return $state === State::MENU_ACTIVE;
	}
}