Flutter Android应用卡在Flutter Logo闪屏界面求助

问题现象 #

写完代码重启应用后，Flutter一直卡在Logo闪屏界面无法进入主页面；但新建的Flutter项目能够正常运行。

环境信息 #

• Windows系统
• VSCode编辑器
• Pixel 8 Pro Android模拟器

已尝试的无效操作 #

• 执行 flutter -v 排查未获取有效线索
• 执行 flutter clean 后问题依旧存在

问题代码（main.dart） #

import 'package:flutter/material.dart';
import 'package:expense_tracker/widgets/expenses.dart';

var kColorScheme =
    ColorScheme.fromSeed(seedColor: const Color.fromARGB(255, 96, 59, 181));
var kDarkColorScheme = ColorScheme.fromSeed(
    brightness: Brightness.dark,
    seedColor: const Color.fromARGB(255, 5, 99, 125));
void main() {
  (fn) {
    runApp(
      MaterialApp(
        darkTheme: ThemeData.dark().copyWith(
          colorScheme: kDarkColorScheme,
          cardTheme: const CardTheme().copyWith(
            color: kDarkColorScheme.secondaryContainer,
            margin: const EdgeInsets.symmetric(
              horizontal: 16,
              vertical: 8,
            ),
          ),
          elevatedButtonTheme: ElevatedButtonThemeData(
            style: ElevatedButton.styleFrom(
                backgroundColor: kDarkColorScheme.primaryContainer,
                foregroundColor: kDarkColorScheme.onPrimaryContainer),
          ),
        ),
        theme: ThemeData().copyWith(
          colorScheme: kColorScheme,
          appBarTheme: const AppBarTheme().copyWith(
            backgroundColor: kColorScheme.onPrimaryContainer,
            foregroundColor: kColorScheme.primaryContainer,
          ),
          elevatedButtonTheme: ElevatedButtonThemeData(
            style: ElevatedButton.styleFrom(
              backgroundColor: kColorScheme.primaryContainer,
            ),
          ),
          cardTheme: const CardTheme().copyWith(
            color: kColorScheme.secondaryContainer,
            margin: const EdgeInsets.symmetric(
              horizontal: 16,
              vertical: 8,
            ),
          ),
          textTheme: ThemeData().textTheme.copyWith(
                titleLarge: TextStyle(
                    fontWeight: FontWeight.bold,
                    color: kColorScheme.onSecondaryContainer,
                    fontSize: 16),
              ),
        ),
        home: const Expenses(),
      ),
    );
  };
}

问题根源 #

main函数内定义了一个匿名函数，但从未执行该函数，导致核心的runApp方法根本没有被调用——应用完成初始化后就停留在闪屏界面，没有后续的页面加载逻辑。

修复方案 #

直接移除多余的匿名函数包裹，让runApp在main函数内直接执行：

void main() {
  runApp(
    MaterialApp(
      darkTheme: ThemeData.dark().copyWith(
        colorScheme: kDarkColorScheme,
        cardTheme: const CardTheme().copyWith(
          color: kDarkColorScheme.secondaryContainer,
          margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
        ),
        elevatedButtonTheme: ElevatedButtonThemeData(
          style: ElevatedButton.styleFrom(
              backgroundColor: kDarkColorScheme.primaryContainer,
              foregroundColor: kDarkColorScheme.onPrimaryContainer),
        ),
      ),
      theme: ThemeData().copyWith(
        colorScheme: kColorScheme,
        appBarTheme: const AppBarTheme().copyWith(
          backgroundColor: kColorScheme.onPrimaryContainer,
          foregroundColor: kColorScheme.primaryContainer,
        ),
        elevatedButtonTheme: ElevatedButtonThemeData(
          style: ElevatedButton.styleFrom(
            backgroundColor: kColorScheme.primaryContainer,
          ),
        ),
        cardTheme: const CardTheme().copyWith(
          color: kColorScheme.secondaryContainer,
          margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
        ),
        textTheme: ThemeData().textTheme.copyWith(
              titleLarge: TextStyle(
                  fontWeight: FontWeight.bold,
                  color: kColorScheme.onSecondaryContainer,
                  fontSize: 16),
            ),
      ),
      home: const Expenses(),
    ),
  );
}

修改代码后重新运行应用，即可正常进入Expenses页面。

内容的提问来源于stack exchange，提问作者Harjith Ramesh