JFreeChart: crosshair label custom position

Question

Is it possible to place crosshair label in the custom position? I have x and y crosshair. I want that y crosshair label was positioned near the data point (change label offset X coordinate).

The problem is that RectangleAnchor has no such option

Crosshair yCrosshair = new Crosshair(Double.NaN, Color.DARK_GRAY, new BasicStroke(0f));
yCrosshair.setLabelAnchor(RectangleAnchor.CENTER);

And it seems that JFreeChart completely ignores label offset settings:

Crosshair yCrosshair = new Crosshair(Double.NaN, Color.DARK_GRAY, new BasicStroke(0f));
yCrosshair.setLabelXOffset(5);

I have the desired plot coordinates for the label in the mouse listener but I can't find how to apply it to the label position.

Why not a `Marker`? You may be able to use `DatasetUtils`, seen [here](https://stackoverflow.com/a/21180275/230513) in an earlier version. A [mcve] may clarify. — trashgod, Mar 20 '19 at 17:33
Marker has similar problems, for some reason absolute offset coordinates are not working correctly marker.setLabelOffset(new RectangleInsets(UnitType.ABSOLUTE, mY, 0, 0, 0)); they are pretty close to correct position when mY is close to the top part of the plot but start drifting heavily to the bottom when mY close to the bottom part of the plot. — Zur13, Mar 21 '19 at 14:26
I've managed to get required results by using Annotations but thanks anyway. — Zur13, Mar 21 '19 at 14:34

score 0 · Accepted Answer · answered Mar 21 '19 at 14:32

Ok I've solved my problem by using XYPointerAnnotation.

XYPointerAnnotation pointer = new XYPointerAnnotation( "", 0, 0, 7.0 * Math.PI / 4.0 ); 
pointer.setTipRadius(3.0); 
pointer.setBaseRadius(15.0); 
pointer.setPaint(Color.blue); 
pointer.setTextAnchor(TextAnchor.HALF_ASCENT_LEFT); 
pointer.setBackgroundPaint(new Color(180, 180, 180, 180));

And on mouse move event I've position the annotation to the desired point

mainPlot.removeAnnotation(pointer);
if ( !sY.isNaN() ) {
    pointer.setX(x);
    pointer.setY(sY);
    pointer.setText("POWER: "+ sY);
    mainPlot.addAnnotation(pointer);
}

JFreeChart: crosshair label custom position

1 Answers1