Question

How do I make a semitransparent black background (of alpha, say 0.5) without using images in QT?

Answer 1

The simplest way I know is to start with this:

setStyleSheet("background:transparent;");
setAttribute(Qt::WA_TranslucentBackground);
setWindowFlags(Qt::FramelessWindowHint);

And then tweak until it works how you want it to from there, originally I found that tip over: on the Qt forums.