QMdiSubWindow with transparency and opacity

scastiello

Hi guys,

I trying to create new QMdiSubWindow with transparency and opacity to be able to see the background of QMdiArea.

I try to overwrite paintEvent like this:

void MdiSubWindow::paintEvent(QPaintEvent *aEvent)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing, true);
    painter.setOpacity(0.5);
    painter.setBrush(Qt::red);
    painter.drawRoundedRect(0, 0 , width(), height(), 20.0, 20.0);

    // QWidget::paintEvent(aEvent);
}

And then a in CSS try this:

QMdiSubWindow {
    border: 1px solid transparent;
    border-radius: 100px;
    opacity: 0.5;
    background: tranparent;
}

QMdiSubWindow QWidget {
    background: transparent;
}

QMdiSubWindow:title {
    height: 18px;
    background: transparent;
}

QMdiSubWindow #accept {
    background: green;
    border: 1px solid #000000;
    margin: 10px;
    border-radius: 5px;
}

QMdiSubWindow #cancel {
    background: red;
    border: 1px solid #000000;
    margin: 10px;
    border-radius: 5px;
}

The window look like this:

Alt text

But i cant remove the default background of QMdiSubWindow. Can anyone help me?

Malek_Khlif

@scastiello You cas use
setAttribute(Qt::WA_NoBackground);
setAttribute(Qt::WA_NoSystemBackground);
setAttribute(Qt::WA_TranslucentBackground);
setAttribute(Qt::WA_DeleteOnClose);

in your MdiSubWindow class

scastiello

It works perfectly , thank you very much. :)

Malek_Khlif

@scastiello ;)

SGaist

Hi,

@Malek_Khlif said:

setAttribute(Qt::WA_DeleteOnClose);

Just beware, that one has nothing to do with painting. Depending on how you handle your mdi sub windows you will have surprises.

Malek_Khlif

Yes of course