Walsi, which OS were you using ??
I was using the same code to change the color of the button...
setPalette(QPalette(QColor(m_color)));
but i was using the button as Flat, and hence the color showed properly. I removed the flat property and it doesnt draw color on the button... i tried various roles like QPalette::Button , etc to change the color, but still no help

Is it bec as Jpn suggested that native themes cause some effects not to have the desired effect ??