[flutter_bloc_0.19.0] MultiBlocProvider

main.dart

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MultiBlocProvider(
      providers: [
        BlocProvider<BlocA>(
          builder: (BuildContext context) => BlocA(),
        ),
        BlocProvider<BlocB>(
          builder: (BuildContext context) => BlocB(),
        ),
        BlocProvider<BlocC>(
          builder: (BuildContext context) => BlocC(),
        ),
      ],
      child: ChildA(),
    );
  }
}