[Riverpod] Async, future, watch in build provider function. Best practice

[Mir1001]

How to implement functionality when one provider needs to wait for data from another?
I need to wait for groupSelectedProvider and playerSelectedProvider to return value (they are returning Future).
Is command await ref.watch(groupSelectedProvider.future); accatable in this case?
The suggested code is working but I think I am missing something.

@Riverpod(keepAlive: true)
class ResultsBestData extends _$ResultsBestData {
  late String _userId;
  late Group _group;
  late User _player;
  // late final stream;

  @override
  Future<ResultsBest> build() async {
    _userId = ref.watch(loggedUserProvider.select((it) => it.id));
    state = AsyncValue.loading();                        //Loading indicator
    _group = await ref.watch(groupSelectedProvider.future);  //HERE
    _player = await ref.watch(playerSelectedProvider.future);
    return _fetchAndSetBestResults();
  }

  Future<ResultsBest> _fetchAndSetBestResults() async {
    state = AsyncValue.loading();
    try {
      final url = Uri.parse(Globals.urlDB + '/user/${_player.id}/group/${_group.groupId}/result/best');
      final response = await http.get(
...

I have tried the suggested watch pair (bottom code), but in this case, I need to return null (or fake object) or an exception. This approach refreshes many times before it gets value. This is an undesired behaviour.

@override
  Future<ResultsBest> build() {
    _userId = ref.watch(loggedUserProvider.select((it) => it.id));
    final selectedGroup = ref.watch(groupSelectedProvider);
    final selectedPlayer = ref.watch(playerSelectedProvider);
    AsyncValue<(Group, User)> _combined = (selectedGroup, selectedPlayer).watch;
    _combined.whenData((pairData) {
      _group = pairData.$1;
      _player = pairData.$2;
       return _fetchAndSetBestResults();
    });
   //return null. or throw exception in build function //HERE
  ...

In my case (top code) do I need to use some dependencies? If so, how?

@Riverpod(keepAlive: true, dependencies: [....]) //HERE
class ResultsBestData extends _$ResultsBestData {...

Thanks

[snapsl]

Using .future is the correct approach here! :)
state = AsyncValue.loading(); is not required as AsyncValue is already set to loading during the first build.