class Part{ int id; String code; String name; int quantity; Part({ this.id, this.code, this.name, this.quantity = 1, }); factory Part.fromJson(Map parsedJson){ return Part( id: parsedJson["id"], code: parsedJson["partNo"], name: parsedJson["partName"], quantity: parsedJson["partQuantity"] == null ? 1 : int.tryParse(parsedJson["partQuantity"].toString()) ?? 1, ); } }