Unhandled Exception: Invalid argument (computation): The type parameter is not nullable: null

Question

Trying to run the following Flutter code in android Studio

Link to code on github https://github.com/cyeh1234/bloc_bug.git

Got the following error:

https://www.mitrais.com/news-updates/getting-started-with-flutter-bloc-pattern/

Correct output

Answer 1

Remove <int> will fix this issue.

await Future.delayed(Duration(seconds: 3));

Answer 2

If you need to specify type annotations use:

await Future<dynamic>.delayed(Duration(seconds: 3));