Flutter编译报错：'nthrow'非类型及垂直视口无界问题求助

问题核心 #

编译错误指向Flutter框架源码文件debug.dart第328行的nthrow，这是拼写错误，正确应为throw。

报错详情 #

Flutter assets will be downloaded from https://storage.flutter-io.cn. Make sure you trust this source!
Launching lib\main.dart on SM A037F in debug mode...
main.dart:1
Flutter assets will be downloaded from https://storage.flutter-io.cn. Make sure you trust this source!
/E:/AppData/new/flutter/packages/flutter/lib/src/rendering/debug.dart:328:13: Error: 'nthrow' isn't a type.
            nthrow FlutterError.fromParts(<DiagnosticsNode>[
            ^^^^^^
/E:/AppData/new/flutter/packages/flutter/lib/src/rendering/debug.dart:328:20: Error: Expected ';' after this.
            nthrow FlutterError.fromParts(<DiagnosticsNode>[
                   ^^^^^^^^^^^^
/E:/AppData/new/flutter/packages/flutter/lib/src/rendering/debug.dart:328:32: Error: Expected an identifier, but got '.'.

Try inserting an identifier before '.'.
            nthrow FlutterError.fromParts(<DiagnosticsNode>[
                               ^
Target kernel_snapshot failed: Exception
2

FAILURE: Build failed with an exception.

* Where:
Script 'E:\AppData\new\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 1201

* What went wrong:
Execution failed for task ':app:compileFlutterBuildDebug'.
> Process 'command 'E:\AppData\new\flutter\bin\flutter.bat'' finished with non-zero exit value 1

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 14s
Exception: Gradle task assembleDebug failed with exit code 1
Exited (sigterm)

出错代码片段 #

if (!constraints.hasBoundedHeight) {
            nthrow FlutterError.fromParts(<DiagnosticsNode>[
              ErrorSummary('Vertical viewport was given unbounded height.'),
              ErrorDescription(
                'Viewports expand in the scrolling direction to fill their container. '
                'In this case, a vertical viewport was given an unlimited amount of '
                'vertical space in which to expand. This situation typically happens '
                'when a scrollable widget is nested inside another scrollable widget.',
              ),
              ErrorHint(
                'If this widget is always nested in a scrollable widget there '
                'is no need to use a viewport because there will always be enough '
                'vertical space for the children. In this case, consider using a '
                'Column or Wrap instead. Otherwise, consider using a '
                'CustomScrollView to concatenate arbitrary slivers into a '
                'single scrollable.',
              ),
            ]);
          }

当前环境信息 #

• Flutter版本：

Flutter 3.10.2 • channel stable • https://github.com/flutter/flutter.git 
Framework • revision 9cd3d0d9ff (12 days ago) • 2023-05-23 20:57:28 -0700
Engine • revision 90fa3ae28f
Tools • Dart 3.0.2 • DevTools 2.23.1

• flutter doctor结果：

Flutter assets will be downloaded from https://storage.flutter-io.cn. Make sure you trust this source!
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 3.10.2, on Microsoft Windows [Version 10.0.19045.2965], locale en-KE)
[√] Windows Version (Installed version of Windows is version 10 or higher)
[√] Android toolchain - develop for Android devices (Android SDK version 32.1.0-rc1)
[√] Chrome - develop for the web
[√] Visual Studio - develop for Windows (Visual Studio Community 2022 17.6.2)
[√] Android Studio (version 2021.2)
[√] VS Code (version 1.78.2)
[√] Connected device (4 available)
[√] Network resources

• No issues found!

解决方案 #

方案1：手动修正源码拼写错误 #

1. 定位到文件：E:/AppData/new/flutter/packages/flutter/lib/src/rendering/debug.dart
2. 找到第328行，将nthrow替换为throw
3. 保存文件后，执行以下命令重新编译：

flutter clean
flutter run

方案2：重新安装Flutter SDK（若不想手动修改源码） #

1. 备份项目的pubspec.yaml文件
2. 删除现有Flutter SDK目录（E:/AppData/new/flutter）
3. 下载对应版本（3.10.2）的Flutter SDK并解压到原目录
4. 配置好环境变量后，进入项目目录执行：

flutter pub get
flutter run

内容的提问来源于stack exchange，提问作者Collins Njoka