颤动一次介绍屏幕？

如果您只想第一次显示介绍屏幕，则需要在本地保存该用户已经看过介绍的屏幕。

对于这种情况，您可以使用Shared
Preference
。有一个用于共享首选项的Flutter软件包，您可以使用

编辑 ：

请参考以下完整的经过测试的代码，以了解如何使用它 ：

import 'dart:async';import 'package:after_layout/after_layout.dart';import 'package:flutter/material.dart';import 'package:shared_preferences/shared_preferences.dart';void main() => runApp(new MyApp());class MyApp extends StatelessWidget {  @override  Widget build(BuildContext context) {    return new MaterialApp(      color: Colors.blue,      home: new Splash(),    );  }}class Splash extends StatefulWidget {  @override  SplashState createState() => new SplashState();}class SplashState extends State<Splash> with AfterLayoutMixin<Splash> {  Future checkFirstSeen() async {    SharedPreferences prefs = await SharedPreferences.getInstance();    bool _seen = (prefs.getBool('seen') ?? false);    if (_seen) {      Navigator.of(context).pushReplacement(          new MaterialPageRoute(builder: (context) => new Home()));    } else {      await prefs.setBool('seen', true);      Navigator.of(context).pushReplacement(          new MaterialPageRoute(builder: (context) => new IntroScreen()));    }  }  @override  void afterFirstLayout(BuildContext context) => checkFirstSeen();  @override  Widget build(BuildContext context) {    return new Scaffold(      body: new Center(        child: new Text('Loading...'),      ),    );  }}class Home extends StatelessWidget {  @override  Widget build(BuildContext context) {    return new Scaffold(      appBar: new AppBar(        title: new Text('Hello'),      ),      body: new Center(        child: new Text('This is the second page'),      ),    );  }}class IntroScreen extends StatelessWidget {  @override  Widget build(BuildContext context) {    return new Scaffold(      appBar: new AppBar(        title: new Text('IntroScreen'),      ),      body: new Center(        child: new Text('This is the IntroScreen'),      ),    );  }}

感谢BenB注意到错误地使用延迟

initState

delay

initState

因此，现在我替换

afterFirstLayout