Change selected tab in TabView given state change in ChangeNotifier - flutter

Question

I have the following class for holding my state:
import 'package:flutter/foundation.dart';
enum ActiveProduct {
HOME,
BURGUNDY,
VIRTUAL
}
class ActiveProductModel extends ChangeNotifier {
ActiveProduct _activeProduct = ActiveProduct.HOME;
ActiveProduct get value => _activeProduct;
void set(ActiveProduct newValue) {
_activeProduct = newValue;
notifyListeners();
}
}
Whenever the "ActiveProduct" changes, I want to change the selected tab in a TabView.
Currently I have setup the application like this:
class MainScaffold extends StatelessWidget {
#override
Widget build(BuildContext context) {
return DefaultTabController(
length: 3,
child: Scaffold(
body: TabBarView(
children: [
Text("hello! abc"),
Text("hello! sdsadsa"),
Text("hello! 231321"),
],
),
),
);
}
}
How can I change the selected tab in the TabBarView when the ActiveProduct changes?
I have tried wrapping the MainScaffold in a Consumer and set the initialIndex value of DefaultTabController. This didn't work however.
I am using the Provider package for state management.

Answer 1

What I would do is transforming your MainScaffold into a StatelessWidget and then, I would not use a DefaultTabController but instead I would use a TabController and pass it as an argument to the TabBarView.
Then in the initState of the MainScaffoldState, I would listen on the ActiveProductModel and use tabController.animateTo(yourpage) whenever something is fired.
I'm not sure that I was very clear in my explanation so here is an example:
class MainScaffold extends StatefulWidget {
#override
_MainScaffoldState createState() => _MainScaffoldState();
}
class _MainScaffoldState extends State<MainScaffold> with SingleTickerProviderStateMixin {
TabController tabController;
/// Just for the example
ActiveProductModel activeProductModel = ActiveProductModel();
#override
void initState() {
// Initiate the tabController
tabController = TabController(vsync: this, length: 3);
activeProductModel.addListener(() {
if (mounted)
/// Here you can do whatever you want, just going to page 2 for the example.
tabController.animateTo(2);
});
super.initState();
}
#override
void dispose() {
tabController.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: TabBarView(
controller: tabController,
children: <Widget>[
Text("hello! abc"),
Text("hello! sdsadsa"),
Text("hello! 231321"),
],
),
);
}
}