QT Transparent Layout

Question

Hello, I am using a vertical layout (QVBoxLayout) to manage buttons. I would like to make its background color as 50% black transparent. Is it possible ?

sw

Answer 1

Ahem... it's been a while since I used Qt, but as far as I know, QVBoxLayout has no background color, so no, it isn't possible. Layout isn't a widget and it isn't being painted at all, it only manages child widget sizes.

If you want to create colored layout, you'll probably have to create a widget with whatever color your want, and then parent QVBoxLayout to that widget.

It'll become more fun if you want color of all layout's children to be affected by color of QVBoxLayout's parent, but I think that "Embedded Dialogs" demo from Qt4 demo may give you an idea about how it can be done.

Answer 2

Depending where you want the border of the transparent area, you will need to group the buttons in a widget (as SigTerm said) and then you can assign a color either via the palette

QPalette palette = widget->palette();
palette.setColor(QPalette::Window, QColor(100,100,100,100));
widget->setPalette(palette);

or use a stylesheet

widget->setStylesheet("QWidget{background-color: rgba(100,100,100,100);}";

the stylesheet has the advantage that you can style all of your application from one spot that is not in the code and set an application wide stylesheet via QApplication::setStylesheet(QString)