QRubberBand like feature - Static selection area - c++

Question

I'm trying to draw a selection area on top of the desktop/opened windows, which works well by using QRubberBand, but seeing as it does not have a stylesheet command, how would I be able to change the color and width of the border and making the inside of it completely transparent?
Edit: Is there a similar method to use than QRubberBand in Qt? Changing the painter methods gives a lot of problems (border is one pixel larger on the left and top than right and bottom, the marked area seems not to be able to be completely transparent).
Edit2: The area it will cover is static, not something that is dragged by the user.
Edit3:
class CustomRubberBand : public QRubberBand
{
public:
CustomRubberBand(Shape s, QWidget * p = 0) : QRubberBand(s, p)
{
}
protected:
void paintEvent(QPaintEvent *pe)
{
Q_UNUSED(pe);
QPainter painter;
QPen pen(Qt::red, 6);
pen.setStyle(Qt::SolidLine);
painter.begin(this);
painter.setPen(pen);
painter.drawRect(pe->rect());
painter.end();
}
};
This gives me the border around it that I want, but I haven't found anything about removing the background (completely transparent) that works... Seems like there is a problem with Vista and Qt with this.
Any tips on how to remove the background? Right now with no painting method for it it is a semi-transparent white background instead of the default blue one.
Edit4:
This shows the problem: Visible background error notice how the background, with the border, is a semi transparent white. The paint method I'm using does not draw this but only the border. I want it to be completely invisible, and setting the opacity for the object will also make the border transparent, which it should not be.

Answer 1

You can use a transparent QPalette in the paintEvent function to achieve what you are trying to do.
class ScreenViewport : public QRubberBand
{
Q_OBJECT
public:
ScreenViewport(Shape shape, QWidget *parent = 0) : QRubberBand(shape,parent){
}
protected:
void paintEvent(QPaintEvent *pe){
pal = new QPalette(Qt::transparent);
setPalette(*pal);
Q_UNUSED(pe);
QPainter painter;
QPen pen(Qt::red, 6);
pen.setStyle(Qt::DashLine);
painter.begin(this);
painter.setPen(pen);
painter.drawRect(pe->rect());
painter.end();
}
private:
QPalette *pal;
};

Answer 2

QRubberBand inherits from QWidget which in turn supports setStyleSheet function, see the QRubberBand member functions listing.
If this is not working right for you just override ::paintEvent , see this example.