glass = new QLabel();
infoTextContainer = new QLabel();
...

QGraphicsOpacityEffect *opacityEffect = new QGraphicsOpacityEffect;
opacityEffect->setOpacity(0.5);
glass->setGraphicsEffect(opacityEffect);

QGraphicsDropShadowEffect *shadowEffect = new QGraphicsDropShadowEffect;
shadowEffect->setColor(QColor(25, 25, 25));
shadowEffect->setXOffset(1);
shadowEffect->setYOffset(1);
infoTextContainer->setGraphicsEffect(shadowEffect);

...
glass->deleteLater();
infoTextContainer->deleteLater();