我想在Dart中使用新的传播语法。
我正在使用Android Studio进行Flutter开发，但收到此错误。
这要求启用--spread-collections实验
ListView(children: [...listTiles, MyWidget()])
但是，我找不到可以指定此选项的任何地方。
我什至无法使其在命令行上工作。flutter --spread-collections run给Could not find an option named "spread-collections".。
flutter --version
Flutter 1.3.8 • channel beta • https://github.com/flutter/flutter.git
Framework • revision e5b1ed7a7f (4 weeks ago) • 2019-03-06 14:23:37 -0800
Engine • revision f4951df193
Tools • Dart 2.2.1 (build 2.2.1-dev.0.0 571ea80e11)
I just updated to flutter version 1.25.0-5.0.pre.92 and I'm getting lots of null-safety related errors in my code which was previously working fine. I have not opted into null safety in any way, all I did was run flutter upgrade, and now it assumes I want to use null safety.
These are the errors:
org-dartlang-app:/pages/lightweight_table/page_lightweight_table.dart:165:81: Error: The parameter 'rowKeys' can't have a value of 'null' because of its type 'List<Key>', but the implicit default value is 'null'.
- 'List' is …最近 Flutter 团队宣布 Dart 语言现在支持声音空安全！并且在 Dart 2.12 和 Flutter 2 中可用。我想将应用程序代码迁移到空安全。
如何将我的包迁移到空安全，
如果有人可以提供有关迁移到 null-safety 的说明，那就太好了。