flutter_green/lib/pages/splash_page.dart

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_green/pages/guide_page.dart';
import 'package:flutter_green/pages/login/welcome_page.dart';
import 'package:shared_preferences/shared_preferences.dart';

/// 闪屏页
class SplashPage extends StatefulWidget {
  @override
  _SplashPageState createState() => _SplashPageState();
}

class _SplashPageState extends State<SplashPage> {
  Future checkFirstSeen() async {
    SharedPreferences preference = await SharedPreferences.getInstance();
    bool _seen = (preference.getBool('guide_flag') ?? false); //如果已经打开过一次，就不展示

    if (_seen) {
      Navigator.of(context).pushReplacement(
          MaterialPageRoute(builder: (context) => WelcomePage())); //主页
    } else {
      preference.setBool('guide_flag', true);
      Navigator.of(context).pushReplacement(
          MaterialPageRoute(builder: (context) => GuidePage())); //第一步，第二步。。
    }
  }

  @override
  void initState() {
    super.initState();
    Timer(Duration(milliseconds: 2000), () {
      checkFirstSeen();
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Stack(
        fit: StackFit.expand,
        children: <Widget>[
          Container(
              decoration: BoxDecoration(color: Color(0xFF6ecce2)),
              child: Column(
                mainAxisAlignment: MainAxisAlignment.start,
                children: <Widget>[
                  Expanded(
                    flex: 2,
                    child: Container(
                      child: Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        children: <Widget>[
                          CircleAvatar(
                            backgroundColor: Color(0xFF28152a),
                            radius: 50.0,
                            child: Image.asset("assets/images/leaf.jpg"),
                          ),
                          Padding(
                            padding: EdgeInsets.only(top: 15.0),
                          ),
                          Text(
                            "欢迎使用绿植App",
                            style: TextStyle(
                                color: Colors.white,
                                fontWeight: FontWeight.bold,
                                fontSize: 24.0),
                          ),
                        ],
                      ),
                    ),
                  ),
                ],
              )),
        ],
      ),
    );
  }
}