PayPal\Api\PaymentHistory::setNextId PHP Method

    public function setNextId($next_id)
    {
        $this->next_id = $next_id;
        return $this;
    }

 public static function createPaymentHistory()
 {
     $history = new PaymentHistory();
     $history->setCount(self::$count);
     $history->setNextId(self::$nextId);
     $history->setPayments(array(PaymentTest::createPayment()));
     return $history;
 }