GTK 4 support

[gavr123456789]

Is there plans for GTK 4 support?

[jhass]

It might be time to extract Gtk specific overrides into its own shard or that is do one for 3 and one for 4. Contributions welcome.

See #35 / 31a2e70

[rubyFeedback]

ruby also doesn't quite have ruby-gtk4 support yet either; I could not even get the hello
world example to work ... :\ (ruby-gtk3 works fine as-is; I am even re-using my CSS
across ruby-gtk applications and web-related stuff).

Oddly enough I was able to compile gtk4 on windows (!) using msys2 some time ago,
so I now declare a race: ruby versus crystal. Which one of these two is going to have
bindings for gtk4 that work on windows as-is first? Taking bets now!

[JeysonFlores]

It's december of 2021 now, What's the state of Gtk4 support on this bindings?

[hugopl]

Unfortunately nobody is paid to work on this, but do so on their free time and when in the mood to do so, so don't expect things to be ready when you want unless you start contributing to the project with code or maybe money.

I started another GTK4 shard mid this year (2021), but I got busy with other things in the last months and didn't have the extra time to work more on it, but if you are interested: https://github.com/hugopl/gtk4.cr/blob/master/examples

However don't expect the shard to be mature at all.