Question

I need to create a qt widget, which will act as a parent for some other widgets, and which will order them.

Now, the question is how do I make it’s background fully transparent?

I thought to do it like this :

struct Imp
{
  Imp( QWidget *parent ) : thisWidget( new QWidget( parent ) )
  {
    thisWidget->setAttribute( Qt::WA_TranslucentBackground, true );
  }

  QWidget *thisWidget;
};

Do you think that I need to set the attribute, or is it going to work fine without it?

Answer 1

By default in Qt4, a QWidget will draw nothing for its own background, and only its children will be drawn. If you want to override that, you specifically have to tell the widget to draw its background via one of its properties. Note that some widgets derived from QWidget will automatically draw backgrounds.