Exception when using MaterialApp.router builder function

[noga-dev]

If the MaterialApp's builder function wraps the child widget with a Scaffold that has a drawer that calls showBottomSheet then this error occurs:

The context used to push or pop routes from the Navigator must be that of a widget that is a descendant of a Navigator widget.)

Or

Null operator used on non null value

If it returns a Dialog instead.

MaterialApp:

Widget build(BuildContext context) => MaterialApp.router(
        routeInformationParser: _router.routeInformationParser,
        routerDelegate: _router.routerDelegate,
        theme: ThemeData.dark(),
        builder: (context, child) => Scaffold(
          drawer: const MainDrawer(),
          body: child,
        ),
      );

MainDrawer:

Widget build(BuildContext context) {
    return Drawer(
      child: Column(
        children: [
          DrawerHeader(
            child: IconButton(
              onPressed: () => showModalBottomSheet<void>(
                context: context,
                builder: (context) => Container(),
              ),
            ),
          ),
        ],
      ),
    );
  }

But if I remove the builder function and have the child itself return a widget wrapped in Scaffold that has the drawer then everything works OK.

It may not be unique to this routing package; I'm just experimenting.

[csells]

@Agondev can you post a complete (but minimal) set of repro code so that I can understand what's going on here?

[noga-dev]

Had to Frankenstein this together. Hopefully it does the trick.

void main() async {
  WidgetsFlutterBinding.ensureInitialized();

  runApp(
    const ProviderScope(child: TestScreen()),
  );
}

final _testRouter = GoRouter(
  initialLocation: '/1',
  debugLogDiagnostics: true,
  errorPageBuilder: (BuildContext context, GoRouterState state) =>
      MaterialPage<void>(
    key: state.pageKey,
    child: const CircularProgressIndicator.adaptive(
      valueColor: AlwaysStoppedAnimation(Colors.red),
    ),
  ),
  routes: [
    GoRoute(
      path: '/1',
      pageBuilder: (context, state) => MaterialPage<void>(
        key: state.pageKey,
        child: const Placeholder(
          color: Colors.green,
        ),
      ),
    ),
    GoRoute(
      path: '/2',
      pageBuilder: (context, state) => MaterialPage<void>(
        key: state.pageKey,
        child: const Placeholder(
          color: Colors.blue,
        ),
      ),
    ),
  ],
);

class TestScreen extends StatelessWidget {
  const TestScreen({Key? key}) : super(key: key);

  @override
  Widget build(context) {
    return MaterialApp.router(
      routeInformationParser: _testRouter.routeInformationParser,
      routerDelegate: _testRouter.routerDelegate,
      theme: ThemeData.dark(),
      builder: (context, child) => SafeArea(
        child: Scaffold(
          drawerEdgeDragWidth: 50,
          drawer: const TestHeader(),
          body: child,
        ),
      ),
    );
  }
}

class TestHeader extends StatelessWidget {
  const TestHeader({
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Drawer(
      child: Column(
        children: [
          DrawerHeader(
            child: IconButton(
              icon: const Icon(
                Icons.accessible_rounded,
                color: Colors.red,
              ),
              onPressed: () => showBottomSheet<void>(
                context: context,
                builder: (context) => BottomSheet(
                  onClosing: () {},
                  builder: (context) => MaterialBanner(
                    content: const Text('test'),
                    actions: [
                      IconButton(
                        onPressed: () {},
                        icon: const Icon(Icons.check),
                      ),
                      IconButton(
                        onPressed: () {},
                        icon: const Icon(Icons.cancel),
                      ),
                    ],
                  ),
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}

showBottomSheet can be swapped with showDialog for the other aforementioned issue.

[noga-dev]

So I still don't know why this occurs, but I can confirm it's definitely unrelated to this package, so I'll just close this issue. Sorry for the trouble.

[csells]

No worries.