Sulu\Bundle\ContactBundle\Contact\AbstractContactManager::unsetMain PHP Method

    public function unsetMain($arrayCollection)
    {
        if ($arrayCollection && !$arrayCollection->isEmpty()) {
            return $arrayCollection->forAll(function ($index, $entry) {
                if ($entry->getMain() === true) {
                    $entry->setMain(false);
                    return false;
                }
                return true;
            });
        }
    }