flutter_tracker/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import 'package:flutter_tracker/pages/login_page.dart';
import 'package:shared_preferences/shared_preferences.dart';

import 'index_page.dart';
import 'model/config.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  Config.initConfig();
  SharedPreferences sharedPreferences = await SharedPreferences.getInstance();
  bool isLogin = sharedPreferences.getBool("isLogin");
  isLogin ??= false;

  runApp(MyApp(
    isLogin: isLogin,
  ));
}

class MyApp extends StatelessWidget {
  bool isLogin = false;

  MyApp({Key key, this.isLogin}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return ScreenUtilInit(
      designSize: const Size(750, 1344),
      builder: () =>
          MaterialApp(
            title: '追踪者',
            theme: ThemeData(
              primarySwatch: Colors.blue,
            ),
            debugShowCheckedModeBanner: false,
            home: isLogin ? IndexPage() : LoginPage(),
          ),
    );
  }
}