【flutter報錯解決】the following dependencies don't support null safety

使用flutter run后，報如下錯誤：

Error: Cannot run with sound null safety, 
because the following dependencies don't support null safety:

 - package:cloud_firestore_web
 - package:firebase_core_web
 - package:shared_preferences
 - package:url_launcher_web
 - package:firebase_auth
 - package:http
 - package:provider
...

For solutions, see https://dart.dev/go/unsound-null-safety
Failed to compile application.

第一種方法

在終端運行

flutter run --no-sound-null-safety

第二種方法

IntelliJ/Android Studio

"Edit Configurations" (在RUN配置里) → "Additional run args" 添加

--no-sound-null-safety

VS Code

在用戶設置里查找"Flutter run additional args"並添加

--no-sound-null-safety

參考Stackoverflow解決方案