Riverpod Flutter: Looking for best way to combine FutureProvider with StateNotifierProvider

Question

I am working on a basic Support Ticket System. I get the Tickets from Firebase (Either as a Stream or Future). I want to allow some Filtering Options (e.g. sort by Status and Category). For this, I thought about using A Future Provider to get the List and a StateNotiferProvider to update the List depending on which filter is being used. This is the code I have so far:

final ticketListStreamProvider =
    RP.FutureProvider((_) => FirestoreService.getTicketList());


class TicketListNotifier extends RP.StateNotifier<List<Ticket>> {
  TicketListNotifier() : super([]);

  void addTicket(Ticket ticket) {
    state = List.from(state)..add(ticket);
  }

  void removeTicket(Ticket ticket) {
    state = List.from(state)..remove(ticket);
  }
}

final ticketsController =
    RP.StateNotifierProvider<TicketListNotifier, List<Ticket>>(
  (ref) => TicketListNotifier(),
);

There are multiple issues I have with that. Firstly it doesn't work. The StateNotifier accepts a List and not a Future<List>. I need to convert it somehow or rewrite the StateNotifier to accept the Future. I was trying to stay close to one of the official examples. (https://github.com/rrousselGit/riverpod/tree/master/examples/todos) Unfortunately, they don't use data from an outside source like firebase to do it.

What's the best approach to get resolve this issue with which combination of providers?

Thanks

Answer 1

1. You can fetch your ticketlist in your TicketListNotifier and set its state with your ticket list.

class TicketListNotifier extends RP.StateNotifier<List<Ticket>> {
  TicketListNotifier() : super([]);

  Future<void> fetchTicketList() async {
    FirestoreService.getTicketList().when(
       //success
       // state = fetched_data_from_firestore
       // error
       // error handle
    )
  }
}

final ticketsController =
    RP.StateNotifierProvider<TicketListNotifier, List<Ticket>>(
  (ref) => TicketListNotifier(),
);

2. Call this method where you want to fetch it /*maybe in your widget's initState method

ref.read(ticketsController.notifier).fetchTicketList();

Now ref.read(ticketsController); will return your ticket list

3. Since you have the ticket list in your TicketListNotifier's state you can use your add/remove method like this:

ref.read(ticketsController.notifier).addTicket(someTicket);