I think you are talking about having JavaFX in a Swing application.
Did you go through the documentation to understand more about it?
The createScene() method would have all JavaFX stuff added to the scene. This scene is then set to the JFXPanel which is a Swing panel - which can then be freely added to a Swing container like JFrame.
So, the SalesReportTopPanel should be JavaFX stuff.
SCJP 1.4, OCMJEA/SCEA 5.0.
subject: I wonder if JPanel and Stage can't be added to Group, how can I create a Panel?