Latest Qt Creator has a animation effect on start , the widget shows from darker to lighter , I don't know which property I should use with Qt's animation framework , to make something similar ?
UPDATE
Ok , i tried to use windowOpacity animation:
QPropertyAnimation *anim = new QPropertyAnimation(this, "windowOpacity", this);
connect(anim, SIGNAL(finished()), SLOT(animationFinished()));
anim->setDuration(1000);
anim->setStartValue(0.0);
anim->setEasingCurve(QEasingCurve::InOutQuad);
anim->setEndValue(1.0);
anim->start(QPropertyAnimation::DeleteWhenStopped);
But , when I disabled "Display compositing" in XFWM4 , the effect wasn't working , but QtCreator still have that.