How to access Provided (Provider.of()) value inside showModalBottomSheet?

Issue

I have a FloatingActionButton inside a widget tree which has a BlocProvider from flutter_bloc. Something like this:

BlocProvider(
  builder: (context) {
    SomeBloc someBloc = SomeBloc();
    someBloc.dispatch(SomeEvent());

    return someBloc;
  },
  child: Scaffold(
    body: ...
    floatingActionButton: FloatingActionButton(
      onPressed: _openFilterSchedule,
      child: Icon(Icons.filter_list),
    ),
  )
);

Which opens a modal bottom sheet:

void _openFilterSchedule() {
    showModalBottomSheet<void>(
      context: context,
      builder: (BuildContext context) {
        return TheBottomSheet();
      },
    );
  }

I am trying to access SomeBloc using BlocProvider.of<SomeBloc>(context) inside TheBottomSheet but I get the following error:

BlocProvider.of() called with a context that does not contain a Bloc of type SomeBloc.

I have tried to use the solution described in https://stackoverflow.com/a/56533611/2457045 but only works for BottomSheet and not ModalBottomSheet.


Note: This is not restricted to BlocProvider or flutter_bloc. Any Provider from the provider package has the same behaviour.

How can I access BlocProvider.of<SomeBloc>(context) inside the showModalBottomSheet?

In case it’s not possible to do that, how to adapt https://stackoverflow.com/a/56533611/2457045 solution to Modal Bottom Sheet?

Solution

InheritedWidgets, and therefore Providers, are scoped to the widget tree. They cannot be accessed outside of that tree.

The thing is, using showDialog and similar functions, the dialog is located in a different widget tree – which may not have access to the desired provider.

It is therefore necessary to add the desired providers in that new widget tree:

void myShowDialog() {
  final myModel = Provider.of<MyModel>(context, listen: false);
  showDialog(
    context: context,
    builder: (_) {
      return Provider.value(value: myModel, child: SomeDialog());
    },
  );
}

Answered By – Rémi Rousselet

Answer Checked By – Willingham (FlutterFixes Volunteer)

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