How to get value when click mouse on the chart?

[shsen]

I create a line chart use DefaultCategoryDataset, and it have several lines, Y axis is number value and X axis is date.
How can I get the value of each line and date at the point when I click mouse on the chart?
Thanks.

[trashgod]

Add a ChartMouseListener, seen here, to your view component.

[shsen]

Thank you for your reply, but the link is show "Human verification"...
Can you copy the sample code to here?
Thanks.

[trashgod]

I see it, too. After verifying, refine your search according to your use case. Failing that, more examples are archived here.

[shsen]

I see many examples use XYPlot, and I use CategoryPlot, so it no use for me...

my code as below:

DefaultCategoryDataset dataset = new DefaultCategoryDataset();
dataset.addValue(500, "Line1", "2023.05.01");
dataset.addValue(300, "Line2", "2023.05.01");
dataset.addValue(700, "Line1", "2023.05.02");
dataset.addValue(500, "Line2", "2023.05.02");
...
chart = ChartFactory.createLineChart("","","",dataset, PlotOrientation.VERTICAL,true,true,false);
...

//show chart Frame:
public class OverlayFrame extends JFrame
{
static JFrame frame = null;
static String strTitle = "";
static class MyPanel extends JPanel implements ChartMouseListener
{
private ChartPanel chartPanel;
public MyPanel(JFreeChart chart)
{
super(new BorderLayout());
this.chartPanel = new ChartPanel(chart);
this.chartPanel.addChartMouseListener(this);
add(this.chartPanel);
}

    public void chartMouseClicked(ChartMouseEvent event)
    {
        /*JFreeChart chart = event.getChart();
        CategoryPlot plot = chart.getCategoryPlot();
        CategoryAxis xAxis = plot.getDomainAxis();
        //plot.setDomainAxis(xAxis);
        Comparable c = plot.getDomainCrosshairColumnKey();
        if (c != null)
        {
            frame.setTitle(c.toString());
        }
        plot.setDomainCrosshairVisible(true);
        plot.setRangeCrosshairVisible(true);*/
        //frame.setTitle(xAxis.getCategoryLabelToolTip(plot.getDomainCrosshairColumnKey()));
        //frame.setTitle(strTitle + "Hello");
    }

    public void chartMouseMoved(ChartMouseEvent event)
    {
        JFreeChart chart = event.getChart();
        CategoryPlot plot = chart.getCategoryPlot();
        Comparable cx = plot.getDomainCrosshairColumnKey();
        Comparable cy = plot.getDomainCrosshairRowKey();
        if (cx != null)
        {
            frame.setTitle(cx + "   " + cy);
        }
        plot.setDomainCrosshairVisible(true);
    }
}

public OverlayFrame(String title, JFreeChart chart)
{
    super(title);
    setContentPane(new MyPanel(chart));
    frame = this;
    strTitle = title;
}

}

so, how to get the value(2 Line have 2 value) and date(only one) to show in frame title???

[trashgod]

Focusing on the mouse event's ChartEntity, the listener below displays each of the four points as the mouse is moved over them.

@Override
public void chartMouseClicked(ChartMouseEvent cme) {
	report(cme.getEntity());
}

@Override
public void chartMouseMoved(ChartMouseEvent cme) {
	report(cme.getEntity());
}

private void report(ChartEntity ce) {
	if (ce instanceof CategoryItemEntity cie) {
		chart.setTitle(cie.getRowKey() + " " + cie.getColumnKey());
	}
}

[shsen]

if (event.getEntity() instanceof CategoryItemEntity)
{
frame.setTitle(((CategoryItemEntity) event.getEntity()).getRowKey() + " " + ((CategoryItemEntity) event.getEntity()).getColumnKey());
}

it can work, thank you. but it is not my request, I want to show the all lines value when the mouse move aross the date column, not the mouse point move in the entity. And show the DomainCrosshair (just use plot.setDomainCrosshairVisible(true))...

[trashgod]

Since your domain axis is a CategoryAxis, it looks like you may be able to use getCategoryStart|Middle|End methods to get the domain bound for each row key; you can then determine which column includes cme.getTrigger().getX().

[shsen]

Thank you！I use JSlider and barely solve the demand.