SVG to alpha channel QPixmaps?

[WinchellChung]

I have an image in *.svg format. I want to load and convert it into a QPixmap object, where the image is opaque where the svg vector lines dictate color, and transparent everwhere else.

I'm currently doing this:

QSvgRenderer renderer;
renderer.load("images/my-logo.svg");
QPixmap image(renderer.defaultSize());
QPainter painter(&image);
renderer.render(&painter);
QLabel *logoLabel = new QLabel(this);
logoLabel->setPixmap(image);

QSvgRenderer renderer;
renderer.load("images/my-logo.svg");
QPixmap image(renderer.defaultSize());
QPainter painter(&image);
renderer.render(&painter);
QLabel *logoLabel = new QLabel(this);
logoLabel->setPixmap(image);

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It puts the svg image into the QLabel, but with an opaque background.
How can I make it with a transparent background?