Starrating widget (WIP)

This is a widget based on the star rating of the library. I made it because I often move from a crate to another and want to be able to rate the current playing tracks fastly (and to get more familiar with mixxx :p ).

I have 2 main questions :
+ Should it inherit from the stareditor of the library or the opposit or none (because the signals/slots are differents...) ?
+ Should I implement support for stylesheets? I did it but when I tried to get the size of the stars + the padding + the borders + the margin with http://qt-project.org/doc/qt-5/qstyle.html#sizeFromContents, I've not been able to make it work : With big margins, the borders always finished over the stars.

Thanks in advance!