overrides.dart

1. 
class UserAuthPageContainer extends StatelessWidget {
  const UserAuthPageContainer({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Consumer((context, read) {
      final authUser = read(authSateChangedProvider).data?.value;
      if (authUser != null) {
        return ProviderScope(
          overrides: [
            listContainersProvider.overrideAs(
              StreamProvider(
                (ref) => listContainerServiceProvider.read(context).listContainers(authUser.email),
              ),
            ),
            userProvider.overrideAs(
              StreamProvider(
                (ref) {
                  return userServiceProvider.read(context).user(uid: authUser.uid);
                },
              ),
            ),
          ],
          child: HomePageContainer(),
        );
      } else {
        return LandingPage();
      }
    });
  }
}







// 2. inside desktop responsive (selecting a list from the left and showing that on the right)

Expanded(
  child: ProviderScope(
    key: ValueKey(homeController.selectedListContainerIndex),
    overrides: [
      listContainerProvider.overrideAs(
        StreamProvider(
          (ref) => listContainerServiceProvider
              .read(context)
              .listContainer(listContainers[homeController.selectedListContainerIndex].id),
        ),
      ),
    ],
    child: const SelectedList(),
  ),
),


//3. on mobile I navigate to the selected List screen so in the beginning I listen to it from firestore
class SelectedListPage extends StatefulWidget {
  static Route<MaterialPageRoute> route(int index, String id) {
    return MaterialPageRoute(
        builder: (context) => SelectedListPage(
              index: index,
              listContainerId: id,
            ),
        settings: const RouteSettings(name: "SelectedList Page"));
  }

  const SelectedListPage({Key key, @required this.index, @required this.listContainerId}) : super(key: key);
  final int index;
  final String listContainerId;

  @override
  _SelectedListPageState createState() => _SelectedListPageState();
}

class _SelectedListPageState extends State<SelectedListPage> {
  static const String _homePage = "Home Page";

  @override
  void initState() {
    if (Platform.isAndroid || Platform.isIOS) analyticsServiceProvider.read(context).logPage("Selected List Page");
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return ProviderScope(
      overrides: [
        listContainerProvider.overrideAs(
          StreamProvider(
            (ref) => listContainerServiceProvider.read(context).listContainer(widget.listContainerId),
          ),
        ),
      ],
      child: WillPopScope(
        onWillPop: () async {
          if (Platform.isAndroid || Platform.isIOS) analyticsServiceProvider.read(context).logPage(_homePage);
          return true;
        },
        child: Scaffold(
          appBar: PreferredSize(
            preferredSize: const Size.fromHeight(100),
            child: SafeArea(
              child: Container(
                height: 100,
                padding: const EdgeInsets.all(12),
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: <Widget>[
                    Row(
                      children: <Widget>[
                        IconButton(
                          icon: const Icon(Icons.arrow_back_ios),
                          iconSize: 38,
                          color: Theme.of(context).textTheme.headline4.color,
                          onPressed: () {
                            if (Platform.isAndroid || Platform.isIOS) analyticsServiceProvider.read(context).logPage(_homePage);
                            Navigator.of(context).pop();
                          },
                        ),
                        const SizedBox(width: 8),
                        Expanded(
                          child: Consumer((context, read) {
                            final listContainer =
                                read(listContainerProvider).data == null ? ListContainer.empty() : read(listContainerProvider).data.value;
                            return Text(
                              listContainer.name,
                              overflow: TextOverflow.ellipsis,
                              style: Theme.of(context).textTheme.headline5,
                            );
                          }),
                        ),
                        Consumer((context, read) {
                          final authuser = read(authSateChangedProvider).data?.value;
                          final listContainer =
                              read(listContainerProvider).data == null ? ListContainer.empty() : read(listContainerProvider).data.value;
                          if (authuser?.uid == listContainer.ownerId) {
                            return ShareListButton(listContainer: listContainer);
                          } else {
                            return const SizedBox();
                          }
                        }),
                        Consumer((context, read) {
                          final listContainer =
                              read(listContainerProvider).data == null ? ListContainer.empty() : read(listContainerProvider).data.value;
                          return SelectedListPopupMenuButton(listContainer: listContainer);
                        }),
                      ],
                    ),
                  ],
                ),
              ),
            ),
          ),
          body: const SelectedList(), // Here I show the SelectedList again as the example 2.
        ),
      ),
    );
  }