chore: migrate to null safety

[TheOneWithTheBraid]

Migrated to null safety

[TheOneWithTheBraid]

@AntoineMarcel Are you willing to accept this PR?

[TheOneWithTheBraid]

Do you have any pending review issues? Could you merge?

[TheOneWithTheBraid]

I would appreciate if you could merge this. In case you are looking for maintainers for the project, please communicate this.

We'd otherwise publish a fork on pub.dev as we do not want to permanently rely on git imports.

[CaptainDario]

@TheOneWithTheBraid could you also update your branch to have the example be null safe?

And also, did you publish a fork on pub?

[TheOneWithTheBraid]

@CaptainDario I correspondingly updated the example and moreover adjusted the gitignore.

Does it look sound now?

No, it wasn't me who published the fork. I always prefer to contribute to existing projects rather than publishing short-time forks.

[TheOneWithTheBraid]

@CaptainDario Does the PR look sound to you? I would love to see this merged & published soon.

[CaptainDario]

@TheOneWithTheBraid looks good to me! However, it seems like you got the wrong idea. I am not a maintainer of this package. I just wanted to use this package and stumbled upon your branch.
That is why I asked if you released a separate package. It looks like this package will never get maintenance and therefore I guess it will make sense to publish a fork as the keyboard shortcut mechanics in flutter are kind of tricky to use (at least in my opinion)...

I would also update the dependencies:

tuple: 2.0.0
visibility_detector: 0.3.3

[TheOneWithTheBraid]

Are you still planning to merge this some day, @AntoineMarcel? Null-safety is nowadays really required for proper Dart code.