Handle user input in custom_backend

[polina-c]

Update custom_backend in a simplest way, so that user input in UI ends up to be recorded in internal variable state of Backend.

[jacobsimionato]

I don't fully understand the request here. Is it that you're looking for how to handle user interaction events when the user taps something in the UI?

That would be GenUiManager.onSubmit. See

genui/packages/flutter_genui/lib/src/core/genui_manager.dart

Line 122 in 3d1d381

Stream<UserMessage> get onSubmit => _onSubmit.stream;

.

[polina-c]

@jacobsimionato

Yes, this helps. Thank you.

I also need to save state of GenUI, that is not submitted yet, so that I can restore user selections after re-rendering. What API should I use?

[polina-c]

genui/examples/travel_app/lib/src/catalog/options_filter_chip_input.dart

Line 131 in 3d1d381

onChanged: (newValue) {