3rd : set color font

Hi,
i need to set color of font of CWindowGc according the background used on phone, how to this?
I use

MAknsSkinInstance* skin = AknsUtils::SkinInstance();
MAknsControlContext* cc = AknsDrawUtils::ControlContext( this );
AknsDrawUtils::Background( skin, cc, this, gc, drawRect );

for the background, but if background is black the text that I write is impossible to read

Many thanks
Silvia