我使用this thread中的代码开发了时间序列JFreeChart。 我想将它添加到我的主面板，其中包含其他四个面板。所以我创建了一个方法
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);
}
}
我在我的一个面板构造函数中调用此代码，如下所示：
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);
}
但是当我将此面板添加到框架时，图形不会动态变化。
答案 0 :(得分：3)
好的，我想我已经发现了你的问题，但是如果没有看到你如何使用这些代码，我就无法完全确定。
你的主要问题在于：
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);
}
在Runnable中，您重新创建PrepareChart的新实例并启动它。这没有任何意义：
PrepareChart实例永远不会启动（因此您看不到它动态更新）相反，我只会使用以下内容：
public JPanel getChartPanel() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
start();
}
});
return new ChartPanel(chart);
}
这是我写的一个小方法，似乎可以解决这个问题。
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);
}
考虑重命名您的类ChartPanel，因为它与JFreeChart的名称相冲突，令人困惑。此外，我没有看到它的使用，因为您可以直接在PrepareChart返回的ChartPanel上执行所有操作。
顺便说一句，将start()的调用放在getter方法中是很奇怪的。