makePurchase method
Opens the Store purchase UI for storeId.
Implementation
@override
Future<StorePurchaseStatus?> makePurchase(String storeId) async {
final result = await methodChannel.invokeMethod<int>(
'makePurchase',
{'storeId': storeId},
);
if (result == null || result < 0 || result > 4) return null;
return StorePurchaseStatus.values[result];
}