CODEWITHSUNDEEP
javaswingjfreechart
mallikarjun
mallikarjun

Reputation: 1862

JFreeChart timeseries is not refreshing

I have developed a timeseries JFreeChart by using code from this thread. I want to add this to my main panel, which contains four other panels. So I created a method 

 package com.garnet.panel;

    import java.awt.*;
    import java.awt.event.*;
    import java.text.*;
    import java.text.SimpleDateFormat;
    import java.util.Calendar;
    import java.util.GregorianCalendar;
    import javax.swing.JPanel;
    import javax.swing.Timer;
    import org.jfree.chart.ChartFactory;
    import org.jfree.chart.ChartPanel;
    import org.jfree.chart.JFreeChart;
    import org.jfree.chart.axis.*;
    import org.jfree.chart.plot.XYPlot;
    import org.jfree.chart.renderer.xy.XYItemRenderer;
    import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
    import org.jfree.data.time.DynamicTimeSeriesCollection;
    import org.jfree.data.time.Second;
    import org.jfree.data.xy.XYDataset;
    import org.jfree.ui.RectangleInsets;
    import org.jfree.ui.RefineryUtilities;


    public class PrepareChart {

    private static final String TITLE = "Dynamic Series";
    private static final int COUNT = 2 * 60;
    private Timer timer;
    private static float lastValue = 49.62f;
    ValueAxis axis;
    DateAxis dateAxis;
    public JFreeChart chart;
    public PrepareChart() {
        super();

        final DynamicTimeSeriesCollection dataset = new DynamicTimeSeriesCollection(1, COUNT, new Second());

      // Get the calender date time which will inserted into time series chart
      // Based on time we are getting here we disply the chart
      Calendar calendar = new GregorianCalendar();
      int date = calendar.get(Calendar.DAY_OF_MONTH);
      int month = calendar.get(Calendar.MONTH);
      int year = calendar.get(Calendar.YEAR);
      int hours = calendar.get(Calendar.HOUR_OF_DAY);
      int minutes = calendar.get(Calendar.MINUTE);
      int seconds = calendar.get(Calendar.SECOND);
       System.out.println("In caht constructor methoed");
      dataset.setTimeBase(new Second(seconds, minutes-2, hours, date, month, year));
      dataset.addSeries(gaussianData(), 0, "Currency Rate");

       chart= createChart(dataset);

        timer = new Timer(969, new ActionListener() {

            float[] newData = new float[1];

            @Override
            public void actionPerformed(ActionEvent e) {
                newData[0] = randomValue();
                System.out.println("In caht timer methoed");
                dataset.advanceTime();
                dataset.appendData(newData);
            }
        });


    }

    private float randomValue() {

      double factor = 2 * Math.random();
      if (lastValue >51){
        lastValue=lastValue-(float)factor;
      }else {
        lastValue = lastValue + (float) factor;
      }
        return  lastValue;
    }
    // For getting the a random float value which is supplied to dataset of time series chart
    private float[] gaussianData() {
        float[] a = new float[COUNT];
        for (int i = 0; i < a.length; i++) {
            a[i] = randomValue();
        }
        return a;
    }

    // This methode will create the chart in the required format
    private JFreeChart createChart(final XYDataset dataset) {  

        final JFreeChart result = ChartFactory.createTimeSeriesChart(TITLE, "hh:mm:ss", "Currency", dataset, true, true, false);

        final XYPlot plot = result.getXYPlot(); 

        plot.setBackgroundPaint(Color.BLACK);
        plot.setDomainGridlinePaint(Color.WHITE);
        plot.setRangeGridlinePaint(Color.WHITE);
        plot.setAxisOffset(new RectangleInsets(5.0, 5.0, 5.0, 5.0));
        plot.setDomainCrosshairVisible(true);
        plot.setRangeCrosshairVisible(true);

        XYItemRenderer r = plot.getRenderer();

        if (r instanceof XYLineAndShapeRenderer) {

            XYLineAndShapeRenderer renderer = (XYLineAndShapeRenderer) r;
                renderer.setBaseShapesVisible(true);

                renderer.setBaseShapesFilled(true);
                renderer.setBasePaint(Color.white);
                renderer.setSeriesPaint(0,Color.magenta);
        }

      dateAxis= (DateAxis)plot.getDomainAxis();

      DateTickUnit unit = null;
      unit = new DateTickUnit(DateTickUnitType.SECOND,30);

      DateFormat chartFormatter = new SimpleDateFormat("HH:mm:ss");
      dateAxis.setDateFormatOverride(chartFormatter);
      dateAxis.setTickUnit(unit);       

      NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
      rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
      rangeAxis.setRange(lastValue-4, lastValue+4);

        return result;
    }

    public void start(){
        timer.start();
    }


    public JPanel getChartPanel(){

        EventQueue.invokeLater(new Runnable() {
            public void run() {
                PrepareChart chart = new PrepareChart(); 
                System.out.println("In caht getter methoed");
                chart.start();
            }
        });
        return new ChartPanel(chart);
    }

}

I am calling this code inside one of my panel constructors like this:

   public class ChartPanel extends JPanel{

    private Dimension dim;
    private PrepareChart chart;
    public JPanel jChart;

    public ChartPanel(){
        dim = super.getToolkit().getScreenSize();
        this.setBounds(2,2,dim.width/4,dim.height/4);
        chart = new PrepareChart();
        jChart =chart.getChartPanel();       

        this.add(jChart);
    }

But when I add this panel to the frame, the graph is not changing dynamically.

Upvotes: 0

Views: 999

Answers (1)

Guillaume Polet
Guillaume Polet

Reputation: 47637

OK, I think I have spotted your problem, but I can't be completely sure without seeing how you use all this code.

Your main issue lies here: 

public JPanel getChartPanel(){

        EventQueue.invokeLater(new Runnable() {
            public void run() {
                PrepareChart chart = new PrepareChart(); 
                System.out.println("In caht getter methoed");
                chart.start();
            }
        });
        return new ChartPanel(chart);
    }

In your Runnable, you recreate a new instance of PrepareChart and you start it. This does not make any sense:

  1. Your enclosing PrepareChart instance is never started (hence you don't see it updated dynamically)
  2. The instance you create in your runnable cannot be reached by anyone/anything so that instance if lost forever in the AWT event-queue.

So instead, I would only be using the following:

public JPanel getChartPanel() {

    EventQueue.invokeLater(new Runnable() {
        @Override
        public void run() {
            start();
        }
    });
    return new ChartPanel(chart);
}

This is a small main method that I wrote which seemed to do the trick.

public static void main(String[] args) {
    PrepareChart prepareChart = new PrepareChart();
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.add(prepareChart.getChartPanel());
    frame.pack();
    frame.setVisible(true);
}

Consider renaming your class ChartPanel because it is conflicting with the names of JFreeChart which is confusing. Also, I don't see the use of it since you could perform all that directly on the ChartPanel returned by PrepareChart.

Btw, it is quite odd to put the call to start() in a getter-method.

Upvotes: 3

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