Update Linux/XDG app settings to delegate theme to new fd.o color-scheme

[andydotxyz]

Updating the app/app_xdg.go function defaultVariant to look up the value now defined "globally" https://github.com/flatpak/xdg-desktop-portal/blob/d7a304a00697d7d608821253cd013f3b97ac0fb6/data/org.freedesktop.impl.portal.Settings.xml#L33-L45

[Jacalz]

I have dug a bit deeper and this appears to be a proper freedesktop specification now that should be supported in Gnome 42 and ElementaryOS 6.1 (probably KDE Plasma in the future as well). This link has pretty much all the details: https://blogs.gnome.org/alexm/2021/10/04/dark-style-preference/

[andydotxyz]

That blog post is helpful, but I still cannot find any documentation that is not in a gnome blog post or wiki ;)

[Jacalz]

True. That part is a bit weird but I think the above link should have most of what is needed to implement it. I did found out about this from the elementary OS 6.1 release notes though: https://blog.elementary.io/elementary-os-6-1-available-now/.

[andydotxyz]

Don't they get it for free from using the latest Gnome libs? i.e. it may still be proposed at the Gnome side rather than ratified standard...

[Jacalz]

Maybe. Seems like they really want it to be a standard though. Maybe the standard just hasn't been published yet? Seems like they have good intentions for making it a standard either way. We are probably closer now than we ever have been with this.

[andydotxyz]

There is now a decent impl to reference pbek/QOwnNotes@3933a89

[metal3d]

I made an implementation here: fyne-io/fyne-x#48

[Jacalz]

@metal3d Would you care to bring the functionality specific to this issue into the main code base here? We already follow light/dark themes on Windows/macOS and it would be great if we do so on Linux as well :)

[metal3d]

Yes, I can propose the theme here.

Of course, as you see, I found ways to follow dark/light theme on Linux, but I think there is a few of decision to take on what I did.
But we can discuss on the PR.

Let me a few minute to make the PR 😄

[metal3d]

This is done here: #3410

[Jacalz]

I think there was a misunderstanding here. I meant the part about only switching the default FyneTheme between dark and light (exactly what this issue relates to), not bringing in everything about icons and such (at least not yet).

[andydotxyz]

I think #3414 should be what you were considering @Jacalz ?

[Jacalz]

Ah, I see. I missed that one, it seems. Thanks :)

[andydotxyz]

Not at all, it is new this morning after some chat in contributor channel last night

[andydotxyz]

Nicely completed, thanks @metal3d