Flutter: How to avoid pushing the same route on existing route

Question

I have view with bottom navigation bar, and when you push a navbar item, a new route is pushed into view.

 final navigatorKey = GlobalKey<NavigatorState>();

 @override
  Widget build(BuildContext context) => MaterialApp(
    home: Scaffold(
      key: _scaffoldKey,
      body: _buildBody(context),
      bottomNavigationBar: _buildBottomNavigationBar(context),
    ),
  );

 void routeToView(routeIndex) {
      navigatorKey.currentState.pushNamed(pagesRouteFactories.keys.toList()[routeIndex]);
  }

I would like to prevent same route being pushed on the current view. I want to compare the current route with new route we are trying to push, and ignore pushing the route if it is same.

I want to scroll the view to the top if it is same route we are trying to push

Any ideas.

Answer 1

NavigatorState doesn't expose an API for getting the path of the current route, and Route doesn't expose an API for determining a route's path either. Routes can be (and often are) anonymous. You can find out if a given Route is on the top of the navigator stack right now using the isCurrent method, but this isn't very convenient for your use case.

https://stackoverflow.com/a/46498543/2554745

This is the closest solution I could think of:

Navigator.of(context).pushNamedAndRemoveUntil(
  "newRouteName",
  (route) => route.isCurrent && route.settings.name == "newRouteName"
      ? false
      : true);

It will pop the current route if name of the route is "newRouteName" and then push new one, else will not pop anything.

Edit: Latest flutter provides ModalRoute.of(context).settings.name to get the name of current route.

Answer 2

This works for me:

    Route route = ModalRoute.of(context);
    final routeName = route?.settings?.name;
    if (routeName != null && routeName != nav) {
      Navigator.of(context).pushNamed(nav);
      print(route.settings.name);
    }