dart - 闪屏中的闪屏实现

我是Flutter的新手，我想在我的应用程序中显示启动画面。我使用了initState()和导航器。但这没有用。该应用程序将打开显示初始屏幕，但之后不会导航到下一个屏幕。

我的main.dart

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

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

 class MyApp extends StatelessWidget{
 @override
 Widget build(BuildContext context) {
    return SplashScreen();
 }
}

class SplashScreen extends StatefulWidget{
  @override
  State<StatefulWidget> createState() {
    return SplashScreenState();
  }
}

class SplashScreenState extends State<SplashScreen>{
  @override
  void initState() {
    super.initState();
    Future.delayed(
      Duration(
        seconds: 4
      ),
      (){
        Navigator.push(
          context,
          MaterialPageRoute(
            builder: (context) => HomePage(),
          )
        );
      }
  );
}
@override
Widget build(BuildContext context) {
  return MaterialApp(
    home: Scaffold(
      backgroundColor: Colors.red,
      body: Text(
        'Welcome to BMI Calculator',
        style: new TextStyle(
          fontSize: 15.0,
          color: Colors.white,
          fontWeight: FontWeight.bold
        ),
      ),
    ),
  );
}
}

还有我的HomePage.dart

import 'package:flutter/material.dart';

class HomePage extends StatelessWidget{
   @override
   Widget build(BuildContext context) {
      return MaterialApp(
        home: Scaffold(
          appBar: AppBar(
            backgroundColor: Colors.red,
             title: Text(
              'BMI Calculator',
               style: new TextStyle(
                 color: Colors.white
               ),
            ),
          ),
        ),
      );
    }
  }

我该如何解决？

由于我是新手，所以我不知道这是否是实现splashScreen的正确方法，如果还有其他更简单的方法，请您也建议一下。

先感谢您。

最佳答案

已更正代码:

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(home: SplashScreen()); // define it once at root level.
  }
}

class SplashScreen extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return SplashScreenState();
  }
}

class SplashScreenState extends State<SplashScreen> {
  @override
  void initState() {
    super.initState();
    Future.delayed(Duration(seconds: 4), () {
      Navigator.push(
          context,
          MaterialPageRoute(
            builder: (context) => HomePage(),
          ));
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.red,
      body: Text(
        'Welcome to BMI Calculator',
        style: new TextStyle(
            fontSize: 15.0, color: Colors.white, fontWeight: FontWeight.bold),
      ),
    );
  }
}

class HomePage extends StatelessWidget{
  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          backgroundColor: Colors.red,
          title: Text(
            'BMI Calculator',
            style: new TextStyle(
                color: Colors.white
            ),
          ),
        ),
    );
  }

}

关于dart - 闪屏中的闪屏实现，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/54575622/