Flutter:是否可以在不按下按钮的情况下自动切换屏幕？

import 'package:flutter/material.dart';
import 'dart:async';

void main() {
  runApp(MyApp());
}

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

class AutoSwitchScreen extends StatefulWidget {
  @override
  _AutoSwitchScreenState createState() => _AutoSwitchScreenState();
}

class _AutoSwitchScreenState extends State<AutoSwitchScreen> {
  Timer _timer;
  int _counter = 0;

  @override
  void initState() {
    super.initState();
    _startTimer();
  }

  @override
  void dispose() {
    _stopTimer();
    super.dispose();
  }

  void _startTimer() {
    const duration = Duration(seconds: 5);
    _timer = Timer.periodic(duration, (Timer timer) {
      setState(() {
        _counter++;
      });
      if (_counter >= 3) {
        _stopTimer();
      }
    });
  }

  void _stopTimer() {
    _timer?.cancel();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Auto Switch Screen'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text(
              'Screen $_counter',
              style: TextStyle(fontSize: 24),
            ),
            SizedBox(height: 20),
            RaisedButton(
              child: Text('Go to next screen'),
              onPressed: () {
                Navigator.push(
                  context,
                  MaterialPageRoute(builder: (context) => NextScreen()),
                );
              },
            ),
          ],
        ),
      ),
    );
  }
}

class NextScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Next Screen'),
      ),
      body: Center(
        child: Text(
          'Next Screen',
          style: TextStyle(fontSize: 24),
        ),
      ),
    );
  }
}