How to provide a BLoC (with flutter_bloc) to `showSearch`

Question

I am using the package flutter_bloc for state management. I want to create a search screen, and found the showSearch Flutter function, and have been having issues providing a BLoC instance to the ListView my SearchDelegate implementation creates. I finally made it work, but would like to ask what the best way of doing this is. Here is the code (excerpts, starting from a button that is placed in an AppBar within a Scaffold):

class ItemSearchButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return IconButton(
      icon: Icon(Icons.search),
      onPressed: () {
        final itemListBloc = context.bloc<ItemListBloc>();
        showSearch(
          context: context,
          delegate: _ItemSearchDelegate(itemListBloc),
        );
      },
    );
  }
}

class _ItemSearchDelegate extends SearchDelegate<String> {
  final ItemListBloc itemListBloc;

  _ItemSearchDelegate(this.itemListBloc);

  // other overridden methods

  @override
  Widget buildSuggestions(BuildContext context) {
    return BlocProvider.value(
      value: itemListBloc,
      child: ItemListWidget(),
    );
  }
}

Basically, the context that invokes the showSearch method has the correct BLoC instance, but it is not available within my SearchDelegate implementation, unless I re-provide it again explicitly in buildSuggestions.

Why is the BLoC not available by default? The showSearch function internally pushes a new Navigator Route, is this the issue?

What is the canonical way of dealing with things like this?

Answer 1

In the end it works as intended - the pushed route has a new context that is not a child of a context that has my BLoC, it is a child of the Navigator. The solution is to either do what I did initially - pass the BLoC explicitly as constructor argument - or make sure the Navigator context has the BLoCs, which is what I eventually did; to do this, make sure the Navigator is a child of the (Multi)BlocProvider.