如何在mobx flutter中跨多个屏幕管理状态？

import 'package:mobx/mobx.dart';

part 'counter_store.g.dart';

class CounterStore = _CounterStore with _$CounterStore;

abstract class _CounterStore with Store {
  @observable
  int count = 0;

  @action
  void increment() {
    count++;
  }
}

import 'package:flutter/material.dart';
import 'package:flutter_mobx/flutter_mobx.dart';
import 'counter_store.dart';

class Screen1 extends StatelessWidget {
  final CounterStore counterStore = CounterStore();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Screen 1'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Observer(
              builder: (_) => Text('Count: ${counterStore.count}'),
            ),
            RaisedButton(
              child: Text('Increment'),
              onPressed: counterStore.increment,
            ),
            RaisedButton(
              child: Text('Go to Screen 2'),
              onPressed: () {
                Navigator.push(
                  context,
                  MaterialPageRoute(
                    builder: (_) => Screen2(counterStore: counterStore),
                  ),
                );
              },
            ),
          ],
        ),
      ),
    );
  }
}

import 'package:flutter/material.dart';
import 'package:flutter_mobx/flutter_mobx.dart';
import 'counter_store.dart';

class Screen2 extends StatelessWidget {
  final CounterStore counterStore;

  Screen2({this.counterStore});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Screen 2'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Observer(
              builder: (_) => Text('Count: ${counterStore.count}'),
            ),
            RaisedButton(
              child: Text('Increment'),
              onPressed: counterStore.increment,
            ),
          ],
        ),
      ),
    );
  }
}