Thank you for providing such an excellent package

[sowiner]

Thank you for providing such an excellent package. I used it to make a small project. It is very easy to use. I have a small suggestion; in addition to the show function, can there be a switch function?

[nank1ro]

Thanks for your kind words 🙏
Can you share some pseudo code of what you're asking for.
I want to understand why you need that widget when there is the Dart switch statement.
If you have an example of what you ideally want to write it will be great 😊

[sowiner]

My thoughts when setting up in-app-purchase, iap has multiple states, such as loading; pending; complete; is it possible to use switch to judge multiple states?

[nank1ro]

You've many options.

Signal

Complete control over the states, more manual work.

sealed class PurchaseState {
  const PurchaseState();
}

class PurchaseComplete extends PurchaseState {
  const PurchaseComplete();
}

class PurchaseFailed extends PurchaseState {
  const PurchaseFailed({
    required this.error,
  });

  final String error;
}

class PurchasePending extends PurchaseState {
  const PurchasePending();
}

class Example extends StatefulWidget {
  const Example({super.key});

  @override
  State<Example> createState() => _ExampleState();
}

class _ExampleState extends State<Example> {
  final purchaseState = Signal<PurchaseState>(const PurchasePending());

  @override
  void initState() {
    super.initState();
    Future.delayed(const Duration(seconds: 1), () {
      purchaseState.value = const PurchaseFailed(error: 'Something went wrong');
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SignalBuilder(
        signal: purchaseState,
        builder: (context, pState, child) {
          return switch (pState) {
            PurchasePending() => const Center(
                child: Text('Purchase pending'),
              ),
            PurchaseComplete() => const Center(
                child: Text('Purchase complete'),
              ),
            PurchaseFailed(error: String e) => Center(
                child: Text('Purchase failed with $e'),
              ),
          };
        },
      ),
    );
  }
}

Resource

I don't know in the specific case if in-app-purchase provides data through a Future or a Stream, but anyway the Resource can handle the 3 most commons states: ready, loading and error.

In addition in the ready case you can use a switch if you have more state to handle.

sealed class PurchaseState {
  const PurchaseState();
}

class PurchaseComplete extends PurchaseState {
  const PurchaseComplete();
}

class PurchasePending extends PurchaseState {
  const PurchasePending();
}

final streamController = StreamController<PurchaseState>();

class Example extends StatefulWidget {
  const Example({super.key});

  @override
  State<Example> createState() => _ExampleState();
}

class _ExampleState extends State<Example> {
  late final purchaseState = Resource(stream: () => streamController.stream);

  @override
  void initState() {
    super.initState();
    Future.delayed(const Duration(seconds: 1), () {
      streamController.addError(Exception('Something went wrong'));
      Future.delayed(const Duration(seconds: 1), () {
        streamController.add(const PurchaseComplete());
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: ResourceBuilder(
          resource: purchaseState,
          builder: (context, resourceState) {
            return resourceState.on(
              ready: (data) {
                return switch (data) {
                  PurchasePending() => const Text('Purchase pending'),
                  PurchaseComplete() => const Text('Purchase complete'),
                };
              },
              error: (error, stackTrace) =>
                  Text('Something went wrong: $error'),
              loading: () => const CircularProgressIndicator(),
            );
          },
        ),
      ),
    );
  }
}

[sowiner]

Thank you, I learned a lesson, I didn’t expect to be able to write like this