getBuyerEntries method
Implementation
Iterable<Entry> getBuyerEntries(String buyerNumber) {
return entries.where((e) {
if (e is SoldEntry) return e.buyerNumber == buyerNumber;
if (e is SellOutPaymentEntry) return e.buyerNumber == buyerNumber;
if (e is ReturnBoxesEntry) return e.buyerNumber == buyerNumber;
return false;
});
}