How to get the series index

[BabakR-alefba]

How to get the index of the point that user clicked on in below code?

spline.setPoint(new HIPoint());
spline.getPoint().setEvents(new HIEvents());
spline.getPoint().getEvents().setClick(new HIFunction(
        f -> {
            Toast t = Toast.makeText(
                this,
                "Clicked point [ " + f.getProperty("x") + ", " + f.getProperty("y") + " ]",
                Toast.LENGTH_SHORT);
                t.show();
            },
            new String[] {"x", "y"}
));