Retrieving the colour of a dataset on a chart

[mminer]

This has perhaps been asked before, but I haven't been able to find the answer through the search function. My question is, how might I retrieve the colour of a dataset on the chart? I'm using JFreeChart in a servlet and have form controls which allow you to add or remove a dataset. For usability, I would like to have the colours of the "remove dataset" list correspond with the colour of the bars on the chart.

Thanks in advance for any solutions.

[david.gilbert]

Each colour is generally asssociated with a series in a chart. One dataset can contain multiple series, so it doesn't really make sense to talk about "the colour of a dataset", except in the special case where each dataset contains a single series.

To find the colour associated with a series, you need to look at the renderer used for the dataset that the series belongs to.

[mminer]

I apologize for the awkward wording, I was indeed referring to the colour of the series. I looked again at the XYLineAndShapeRenderer and XYBarRenderer classes (these are the renderers I'm using) and could only find methods which return a Paint object. This sounds promising, but I'm unsure how I can use this to find the actual colour of the series. I would like to retrieve the RGB values in 0-255 integers, or something similar which can be converted to a hex code to put on a cascading style sheet. Any thoughts?

[mminer]

I've found a solution to my problem. When I get the Paint object that is used to colour the bars in the XYBarRenderer, I cast it to a Color object on which I can then run functions like getRGB(), getRed(), etc. From looking at the javadoc for java.awt.Paint it wasn't obvious to me that this could be done, but it does work.

Code: Select all

XYBarRenderer renderer = new XYBarRenderer();
Paint paint = renderer.getSeriesFillPaint(0);
Color color = (Color)paint;
System.out.println(color.getRGB());

Perhaps this is obvious for people who have dealt with Java's Paint and Color classes before, but I'm certain I won't be the only person confused by them (or at least, one can hope).