How to use method from one Change notifier class in another change notifier class provider

Question

I want to use fetchdata() in another provider method and initialise variables.

Answer 1

you can use MultiProvider with ChangeNotifierProxyProvider

1. Action Class ( FirstModel )

    class FirstModel with ChangeNotifier {
    List<Strings> _names = ["Sat", "Sat2", "Sat3"];
   
    List<Strings> get names {
       return _names ;
    }
    }
   

2. Action Class ( SecondModel )

    class SecondModel with ChangeNotifier {        
    SecondModel(this.firstModel);
   
    final FirstModel firstModel;
    List<Strings> getNames(){
       return firstModel.names;
    }
    }
   

In main.dart just update the Multiprovider, example below

void main() {
  runApp(
    MultiProvider(
      providers: [
        ChangeNotifierProvider<FirstModel>(create: (_) => FirstModel()),
        ChangeNotifierProxyProvider0<SecondModel>(
          create: (BuildContext context) =>
              SecondModel(Provider.of<FirstModel>(context, listen: false)),
          update: (BuildContext context, SecondModel secondModel) =>
              SecondModel(Provider.of<FirstModel>(context, listen: false)),
        ),
      ],
      child: MyApp(),
    ),
  );
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

Similar other class also avilable... For More Information please refer below link...

ChangeNotifierProxyProvider0 class API