Question

I’m currently working with time-series data and I’m using JFreeCharts XYLineChart to display my data. For my user interface I want to create click-able thumbnails of these charts (which then show the real big Chart).

I tried this method to create a thumbnail of the chart, but I don’t know how I can use this BufferedImage to display the thumbnail.

XYSeriesCollection coll = new XYSeriesCollection();
coll.addSeries(rw.getT1().getCurMktCapSeries());
coll.addSeries(rw.getT2().getCurMktCapSeries());            
JFreeChart chart = ChartFactory.createXYLineChart(rw.getT1().getName() + " - " + rw.getT2().getName(),
                                            "Position",
                                            "Course",
                                            coll,
                                            PlotOrientation.VERTICAL,
                                            true,
                                            true,
                                            false);
    
BufferedImage bi = chart.createBufferedImage(1000, 1000, 100, 100, null);

I tried searching online, but the only thing I found was the method above to create a thumbnail, not how to display it.

So my question are:

• Is this the right way to create a thumbnail?
• How can I display this thumbnail on my GUI?

Solution

I just created my own custom JPanel

public class ImagePanel extends JPanel

and then I added the following paintComponent method to draw the thumbnail

protected void paintComponent(Graphics g) {
    super.paintComponents(g);
    //Create Image
    BufferedImage bi = this.createBufferedImage(this.rw);
    //Draw Background
    Graphics2D g2d = (Graphics2D)g;
    g2d.setColor(this.backgroundColor);
    g2d.fillRect(0, 0, this.getWidth(), this.getHeight());
    //Draw Image
    g2d.drawImage(bi.getScaledInstance(this.getWidth()-10, this.getHeight()-10, 0), 5, 5, this.backgroundColor, null);
}

To create the BufferedImage I used the following method

private BufferedImage createBufferedImage(ResultWrapper rw2) {
    //Create JFreeChart
    XYSeriesCollection coll = new XYSeriesCollection();
    coll.addSeries(rw.getT1().getCurMktCapSeries());
    coll.addSeries(rw.getT2().getCurMktCapSeries());            
    JFreeChart chart = ChartFactory.createXYLineChart(null, null, null, coll, PlotOrientation.VERTICAL, false, true, false);
    
    //Hide Axis
    XYPlot plot = chart.getXYPlot();
    plot.getRangeAxis().setVisible(false);
    plot.getDomainAxis().setVisible(false);
    
    return chart.createBufferedImage(500, 500, 100, 100, null);
}

With that I got exactly what I wanted, little thumbnails of a JFreeChart. To make it clickable, just add a MouseListener.

Thanks @MadProgrammer for using a custom component and the paintComponent method

Answer 1

Ontop of AndrewThompon’s suggestions, you could provide a custom Component that has the ability to paint the chart.

Take a look at

• Performing Custom Painting in Swing
• Java Graphcs2D

This is by far more involved then has already been suggested, but does provide you with the greatest of flexibility