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I have a FutureProvider with a List of items. How can I update an item in this list without a refresh the provider?

Nidhal
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    FutureProvider does not yet support query mutation; you will need to manage the state yourself, like StateNotifier or Notifier, or use ref.invalidate to refresh the list. https://github.com/rrousselGit/riverpod/issues/1660 – user12208004 Feb 21 '23 at 05:31

2 Answers2

2

You should use a StateNotifierProvider for your list like this:

final listProvider = StateNotifierProvider<ListItem, dynamic>((ref) {
  return ListItem([]);
});

class ListItem extends StateNotifier<dynamic> {
  ListItem(List<dynamic> items) : super(items);
  void update(dynamic item) {
     // Your update logic. You have access to the use with 'state' variable
  }
}

Before that you populate the listProvider with your future response. Also you should change the dynamic type to your object type on the list

Jonatan Orozco
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    Yeah but I wanted to use futureProvider to be able to use ref.watch(myFutureProvider).when(data: data, error: error, loading: loading) and update a the state without refreshing and fectching the data again. – Nidhal Apr 13 '22 at 21:24
  • What about using another FutureProvider receiving your update? You await your original provider, but fetch your updated state. – Jonatan Orozco Apr 15 '22 at 22:18
  • no he should not as that was not the question. He might use `ref.refresh()` somewhere. This answer is only helpful to a whole different scenario – MwBakker May 10 '23 at 10:46
2

You can get the data you need from the creation function of the FutureProvider. This will be executed on every update of the otherProvider. So all you need to do is update this otherProvider value and your future will refresh automatically.

 late final FutureProvider<List<String>> allStrings = FutureProvider((ref) {
      var aNewValue = ref.watch(otherProvider);
      return _externalService.getMyStringsFromSomewhere();
  });
James
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