jfreechart-fx | Extensions for JFreeChart to support JavaFX client

I haven't looked at jFreeChart in detail, but I think the main difference between it and the in-built JavaFX charting API is that jFreeChart uses a canvas for its implementation, whereas the in-built charts use the scene graph. Roughly, though not exactly, its similar to this definition of a retained mode (scene graph) vs immediate mode (canvas).

It's probably possible to add interactivity to canvas rendered graphics. It is likely technically challenging beyond basic whole-chart zoom and drag ops. Implementing or demonstrating the addition of such interactivity with canvas rendered graphics is beyond what I would be prepared to do within the context of a StackOverflow answer.

JFreeChart includes an interaction package:

• https://github.com/jfree/jfreechart-fx/tree/master/src/main/java/org/jfree/chart/fx/interaction

I suggest you investigate the interaction package, try using it and see if it offers the level of interaction you need.

As Roger mentions in the comments, you can get some basic interaction on a JFreeChartFX chart by wrapping the chart in a ChartViewer using ChartViewer(JFreeChart myChart).

Related question:

• How do I properly add a MouseHandler to my JFreeChart-FX to drag the chart from left to right

An aside on Canvas vs SceneGraph

This info on how canvas works is included so that you might have a better idea of what is going on here (note everything here may not be 100% correct, but is close enough to help understanding).

Technically, JavaFX only uses a SceneGraph for rendering. How canvas is internally implemented, as far as I understand, is that each canvas is a node in the scenegraph and comes with a command queue of drawing instructions. When you draw to the canvas, it doesn't draw immediately, instead it puts the drawing commands into a queue, then, at some point, before the next 60fps drawing pulse completes, it renders those to an image buffer that it relays into a JavaFX node. Old commands are forgotten by the canvas command queue once executed, so everything just ends up as pixels eventually. You can keep track of drawing commands within your application and re-issue them to repaint the canvas from scratch if you wish, but canvas won't help with that.

What JFreeChartFX is doing is providing an adapter which makes a JavaFX canvas look like a Swing painting surface, so that the heavy lifting and internal engine of JFreeChart can be used to issue all of the drawing commands, and those can be rendered to either a JavaFX canvas or Swing canvas depending upon the desired output UI tech.

If JFreeChart also provided a similar adapter for JavaFX events, rather than Swing events, and if JFreeChart already has a way to do interactivity using Swing events, then it could potentially add interactivity to JFreeChartFX using a similar adapter or replacement for Swing event mechanisms. Perhaps that is what the interaction package linked above is doing.