Flutter Null 安全迁移说“包不存在”
Flutter Null Safety Migration says `Package doesn't exist`
Flutter 空安全迁移
我正在尝试将我的项目迁移到 Flutter Null Safety Version，并且我正在关注 this 官方迁移指南。
当我 运行 第二个命令时它说
Package doesn't exist (the Flutter SDK is not available).
命令一 运行
me@My-MacBook-Air my_project % dart --version
Dart SDK version: 2.12.0 (stable) (Thu Feb 25 19:50:53 2021 +0100) on "macos_x64"
me@My-MacBook-Air my_project % dart pub outdated --mode=null-safety
Package doesn't exist (the Flutter SDK is not available).
Flutter Doctor 输出
me@My-MacBook-Air my_project % `flutter doctor -v`
Flutter (Channel beta, 2.0.2, on macOS 11.2.3 20D91 darwin-x64, locale en-IN)
• Flutter version 2.0.2 at /Users/me/flutter
• Framework revision 8962f6dc68 (9 days ago), 2021-03-11 13:22:20 -0800
• Engine revision 5d8bf811b3
• Dart version 2.12.1
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
• Android SDK at /Users/me/Library/Android/sdk
• Platform android-30, build-tools 30.0.2
• ANDROID_HOME = /Users/me/Library/Android/sdk
• Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
• All Android licenses accepted.
[✓] Xcode - develop for iOS and macOS
• Xcode at /Applications/Xcode.app/Contents/Developer
• Xcode 12.4, Build version 12D4e
• CocoaPods version 1.10.1
[✓] Chrome - develop for the web
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
[✓] Android Studio (version 4.1)
• Android Studio at /Applications/Android Studio.app/Contents
• Flutter plugin can be installed from:
https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
[✓] VS Code (version 1.51.1)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension version 3.17.0
[✓] Connected device (2 available)
• macOS (desktop) • macos • darwin-x64 • macOS 11.2.3 20D91 darwin-x64
• Chrome (web) • chrome • web-javascript • Google Chrome 89.0.4389.90
• No issues found!
在这里看不到任何明显的东西，该命令只是一个查找，您仍然可以检查 pub.dev 手册中的所有依赖项，当所有软件包都支持 null 安全并且其他命令正常工作时，您应该没问题。
我只有一个想法，在大多数情况下测试版应该没问题，但如果没有任何效果，请切换到稳定版
flutter channel stable
确保你 运行 flutter upgrade
尝试flutter pub outdated --mode=null-safety，应该会显示包依赖项的迁移状态。
第一个运行:
dart pub outdated --mode=null-safety
并将您的软件包升级到 null-safe 变体，运行:
dart pub upgrade --null-safety
Flutter 空安全迁移
我正在尝试将我的项目迁移到 Flutter Null Safety Version，并且我正在关注 this 官方迁移指南。
当我 运行 第二个命令时它说
Package doesn't exist (the Flutter SDK is not available).
命令一 运行
me@My-MacBook-Air my_project % dart --version
Dart SDK version: 2.12.0 (stable) (Thu Feb 25 19:50:53 2021 +0100) on "macos_x64"
me@My-MacBook-Air my_project % dart pub outdated --mode=null-safety
Package doesn't exist (the Flutter SDK is not available).
Flutter Doctor 输出
me@My-MacBook-Air my_project % `flutter doctor -v`
Flutter (Channel beta, 2.0.2, on macOS 11.2.3 20D91 darwin-x64, locale en-IN)
• Flutter version 2.0.2 at /Users/me/flutter
• Framework revision 8962f6dc68 (9 days ago), 2021-03-11 13:22:20 -0800
• Engine revision 5d8bf811b3
• Dart version 2.12.1
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
• Android SDK at /Users/me/Library/Android/sdk
• Platform android-30, build-tools 30.0.2
• ANDROID_HOME = /Users/me/Library/Android/sdk
• Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
• All Android licenses accepted.
[✓] Xcode - develop for iOS and macOS
• Xcode at /Applications/Xcode.app/Contents/Developer
• Xcode 12.4, Build version 12D4e
• CocoaPods version 1.10.1
[✓] Chrome - develop for the web
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
[✓] Android Studio (version 4.1)
• Android Studio at /Applications/Android Studio.app/Contents
• Flutter plugin can be installed from:
https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
[✓] VS Code (version 1.51.1)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension version 3.17.0
[✓] Connected device (2 available)
• macOS (desktop) • macos • darwin-x64 • macOS 11.2.3 20D91 darwin-x64
• Chrome (web) • chrome • web-javascript • Google Chrome 89.0.4389.90
• No issues found!
在这里看不到任何明显的东西，该命令只是一个查找，您仍然可以检查 pub.dev 手册中的所有依赖项，当所有软件包都支持 null 安全并且其他命令正常工作时，您应该没问题。
我只有一个想法，在大多数情况下测试版应该没问题，但如果没有任何效果，请切换到稳定版
flutter channel stable
确保你 运行 flutter upgrade
尝试flutter pub outdated --mode=null-safety，应该会显示包依赖项的迁移状态。
第一个运行:
dart pub outdated --mode=null-safety
并将您的软件包升级到 null-safe 变体，运行:
dart pub upgrade --null-safety