"Configure Language" option

[Friedrich W. H. Kossebau]

Am Dienstag, 25. Oktober 2022, 17:16:15 CEST schrieb Friedrich W. H. Kossebau:
> Am Montag, 24. Oktober 2022, 23:38:15 CEST schrieb Stefan Gerlach:
> > i noticed that several KDE apps lack the ability to switch the UI language
> > when using the "Configure Language" dialog. The .mo files are correctly
> > installed, all the languages are in the selection box and the
> > configuration
> > is saved in the klanguageoverridesrc file which is read on startup. But
> > somehow (most of) the UI strings are shown in the system language only.

On a second read I see you actually talk about the custom app language 
feature. Was getting off the path here by all the other issues I saw in the 
normal Step run and the rabbit holes I had to enter there :)

Now gave that another try, with Step, given I was already warm with the 
codebase, and tested by using French as custom language over my system German. 
And saw that indeed some UI terms were still in German language, despite there 
being a French qm file.

Looking into the code, there might be chance for a race condition:
the custom code generated by the cmake macro ecm_create_qm_loader (from 
ECMPoQmTools) uses Q_COREAPP_STARTUP_FUNCTION to hook the QTranslator 
generation code for that catalog into the startup during the QApp instance 
creation.

Though the code from kxmlgui which does checking of the klanguageoverridesrc 
config and then trying to adjust things by setting the LANGUAGE env var 
respectively also uses Q_COREAPP_STARTUP_FUNCTION. 

So there might be some chance of race condition. And things only worked by 
chance at least for the tier1 KF libraries which use that because the 
registered functions are done in an order after the kxmlgui one, due to the 
order of libraries that are loaded and their static data is initialized? But 
then fail for anything else whose hook is executed before the kxmlgui one, as 
the ecm_create_qm_loader code seems to not have any update logic?

As I dislike the Qt translation system personally, myself have sadly to opt 
out here. Hopefully there are others with energy on that matter here.

Cheers
Friedrich