Styles, QSS and KMainWindow

[Dario Freddi]

Hello everyone,

today I was playing around with some qss styles for a KDE application (KMess). 
Everything worked correctly, except from background settings. It looks like 
every background: directive on the main widget embedded in a KMainWindow is 
ignored. I tried setting the background directive to all QWidgets, and all the 
widgets behaved correctly, except the ones embedded in the KMainWindow.

This brings me to believe that the style of every widget that gets as a parent 
KMainWindow gets overridden by KDE. Is there a way to avoid this? If not, I 
think we should give the possibility from 4.3 on, since QSS is really powerful 
and is surely an option we should give. Forgot to mention: the same thing in a 
Qt-only application works correctly.

Cheers
Dario