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JFreeChart MeterPlot

I am currently running an Agent project in java. At some point, I need to show a meter, for example: battery level. I have 5 agents in my program, each agent creates its own counter with a name on it, but somehow they do not update the dataset. OR they only update the dataset so that it is not displayed on the meter. Any idea?

Below is my code: car.java

{
    private CarMeter meter;
    meter = new CarMeter(getLocalName());
    meter.update(currentBatteryCharge);
}

meterplot.java

public class CarMeter extends ApplicationFrame {

 private static DefaultValueDataset dataset1;

public CarMeter(String s) {
    super(s);
    JPanel panel = createPanel();
    panel.setPreferredSize(new Dimension(500, 350));
    setContentPane(panel);
    pack();
    setVisible(true);
}

public CarMeter() {
    super("s");
    JPanel panel = createPanel();
    panel.setPreferredSize(new Dimension(500, 350));
    setContentPane(panel);
    pack();
    setVisible(true);
}

private static JFreeChart createChart(ValueDataset valuedataset) {
    MeterPlot meterplot = new MeterPlot(valuedataset);
  //set minimum and maximum value
    meterplot.setRange(new Range(0.0D, 100000D));

    meterplot.addInterval(new MeterInterval("Battery LOW", new Range(0.0D, 10000D), 
            Color.red, new BasicStroke(2.0F), new Color(255, 0, 0, 128)));

    meterplot.addInterval(new MeterInterval("Moderate", new Range(10001D, 90000D), 
            Color.yellow, new BasicStroke(2.0F), new Color(255, 255, 0, 64)));

    meterplot.addInterval(new MeterInterval("Battery FULL", new Range(90001D, 100000D),
            Color.green, new BasicStroke(2.0F), new Color(0, 255, 0, 64)));

    meterplot.setNeedlePaint(Color.darkGray);
    meterplot.setDialBackgroundPaint(Color.white);
    meterplot.setDialOutlinePaint(Color.black);
    meterplot.setDialShape(DialShape.CHORD);
    meterplot.setMeterAngle(180);
    meterplot.setTickLabelsVisible(true);
    meterplot.setTickLabelFont(new Font("Arial", 1, 12));
    meterplot.setTickLabelPaint(Color.black);
    meterplot.setTickSize(5D);
    meterplot.setTickPaint(Color.gray);
    meterplot.setValuePaint(Color.black);
    meterplot.setValueFont(new Font("Arial", 1, 14));
    JFreeChart jfreechart = new JFreeChart("Battery Level",
            JFreeChart.DEFAULT_TITLE_FONT, meterplot, true);
    return jfreechart;
}

public static JPanel createPanel() {
    dataset1 = new DefaultValueDataset(0);
    JFreeChart chart = createChart(dataset1);
    ChartPanel chartpanel = new ChartPanel(chart);
    return chartpanel;
}

public void update(int data){
dataset1.setValue(data);
System.out.println(""+dataset1 +" " +data);
}
+2
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2 answers

As @ alex2410 noted, your code works as shown below. As noted in the answer provided by @Outlaw, the plot (view) listens on the data set (model). Some notes

  • Do not repeat the code in the constructors; let one call the other.

  • setPreferredSize(), getPreferredSize().

  • .

  • .

  • , .

image

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JPanel;
import javax.swing.Timer;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.DialShape;
import org.jfree.chart.plot.MeterInterval;
import org.jfree.chart.plot.MeterPlot;
import org.jfree.data.Range;
import org.jfree.data.general.DefaultValueDataset;
import org.jfree.data.general.ValueDataset;
import org.jfree.ui.ApplicationFrame;

public class CarMeter extends ApplicationFrame {

    private DefaultValueDataset dataset;
    private int value = 50000;

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                new CarMeter();
            }
        });
    }

    public CarMeter(String s) {
        super(s);
        JPanel panel = createPanel();
        setContentPane(panel);
        pack();
        setLocationRelativeTo(null);
        setVisible(true);
        Timer t = new Timer(250, new ActionListener() {
            Random r = new Random();

            @Override
            public void actionPerformed(ActionEvent e) {
                value -= (int) (Math.abs(100 * r.nextGaussian()));
                update(value);
            }
        });
        t.start();
    }

    public CarMeter() {
        this("Test");
    }

    private JFreeChart createChart(ValueDataset valuedataset) {
        MeterPlot meterplot = new MeterPlot(valuedataset);
        meterplot.setRange(new Range(0.0D, 100000D));
        meterplot.addInterval(new MeterInterval("Battery LOW", new Range(0.0D, 10000D),
            Color.red, new BasicStroke(2.0F), new Color(255, 0, 0, 128)));
        meterplot.addInterval(new MeterInterval("Moderate", new Range(10000D, 90000D),
            Color.yellow, new BasicStroke(2.0F), new Color(255, 255, 0, 64)));
        meterplot.addInterval(new MeterInterval("Battery FULL", new Range(90000D, 100000D),
            Color.green, new BasicStroke(2.0F), new Color(0, 255, 0, 64)));

        meterplot.setNeedlePaint(Color.darkGray);
        meterplot.setDialBackgroundPaint(Color.white);
        meterplot.setDialOutlinePaint(Color.black);
        meterplot.setDialShape(DialShape.CHORD);
        meterplot.setMeterAngle(180);
        meterplot.setTickLabelsVisible(true);
        meterplot.setTickLabelFont(new Font("Arial", 1, 14));
        meterplot.setTickLabelPaint(Color.black);
        meterplot.setTickSize(5D);
        meterplot.setTickPaint(Color.gray);
        meterplot.setValuePaint(Color.black);
        meterplot.setValueFont(new Font("Arial", 1, 14));
        JFreeChart jfreechart = new JFreeChart("Battery Level",
            JFreeChart.DEFAULT_TITLE_FONT, meterplot, true);
        return jfreechart;
    }

    private JPanel createPanel() {
        dataset = new DefaultValueDataset(value);
        JFreeChart chart = createChart(dataset);
        ChartPanel chartpanel = new ChartPanel(chart) {
            @Override
            public Dimension getPreferredSize() {
                return new Dimension(640, 480);
            }
        };
        return chartpanel;
    }

    public void update(int data) {
        dataset.setValue(data);

    }
}
+4

, Jfreechart -

- , , .

createChart ( ) .

, . GOF, http://en.wikipedia.org/wiki/Observer_pattern.

+1

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