RFC: Theming and styles of KDE applications

[christoph at cullmann.io]

On 2024-05-05 20:52, christoph at cullmann.io wrote:
> On 2024-05-04 22:36, christoph at cullmann.io wrote:
>> On 2024-05-04 21:56, Akseli Lahtinen wrote:
>>> On Saturday 4 May 2024 14:47:35 GMT+3 christoph at cullmann.io wrote:
>>>> My proposal: we enforce Breeze as icon set and style everywhere. And 
>>>> we
>>>> provide still a way to overwrite that for the user, but if the user
>>>> didn't set something manually,  idenpendent what the system propose, 
>>>> we
>>>> just use Breeze. And we depend on that as dep e.g. in Kate, if you
>>>> install Kate, that icon set and theme is installed.
>>> 
>>> +1. For me as someone who changes icons sometimes just to see and 
>>> tinker
>>> around,
>>> i think this makes sense. We have reliable fallback, but we still 
>>> allow
>>> users to customize things which is, well, our thing! :)
>>> 
>>> And if the custom icons break i do not end up with broken apps, so
>>> i really do not see any downside here, as user or dev perspective.
>> 
>> Yes, if some user switches a theme or style in our system settings
>> or in the application (like we do it with the color scheme switcher 
>> some
>> applications like Kate have) that is fine.
>> 
>> But beside that, we should just force our default style and icon set,
>> like we do on Windows and macOS already, that will even make some 
>> patches
>> and ifdef's useless we need now to sprinkle in all apps we really 
>> support on
>> these platforms.
> 
> Hi,
> 
> I have now two drafts for both the icon theme/engine and the style
> enforcing:
> 
> https://invent.kde.org/frameworks/kiconthemes/-/merge_requests/136
> https://invent.kde.org/frameworks/kconfigwidgets/-/merge_requests/239
> 
> Testing and feedback (and help) is welcome.
> 
> This would be opt-in, e.g. Kate would call
> 
>     KIconTheme::initTheme()
> 
> before the QApplication construction and
> 
>     KStyleManager::initStyle()
> 
> after it and that would ensure the full setup.

Hi,

That stuff is now merged and ready for KF 6.3.

There are still open issues like that we need some extra Qt 
API/extension
like

https://codereview.qt-project.org/c/qt/qtbase/+/559108

to have really the same integration outside of Plasma session,
but it is already at lot nicer outside of Plasma.

If you have time to help out, we use

https://invent.kde.org/frameworks/kiconthemes/-/issues/3

to coordinate that a bit.

Greetings
Christoph