Why cant you show the clock as it is ? It seems to be inherited from QWidget, and you can simply use it as another widget in your application.

But say if you want to show that clock as pixmap in a label, you can do this -
1. Use a timer of say 200ms. In the timeout event call AnalogClock::render() [see QWidget::render]. Now you have rendered the clock on a pixmap, set this new pixmap onto yuor label.

2. You can inherit from QLabel and in the painevent of that label, do the rendering as above.