bills = new Collection; } /** * @param BillLine $bill */ public function addBill(BillLine $bill) { $this->bills->push($bill); } /** * @return Collection */ public function getBills() { $set = $this->bills->sortBy( function (BillLine $bill) { $active = intval($bill->getBill()->active) == 0 ? 1 : 0; $name = $bill->getBill()->name; return $active . $name; } ); return $set; } }