我正在尝试从串口读取一些数据并使用JFreeChart和ChartPanel显示相同的数据。 点击“Aquire”按钮后，我从串口获取新的数据集。首次显示面板时，将显示从串行端口读取的值。单击“Aquire”按钮后，值将填充在变量“dataset”中，但它们不会在图形上刷新。我哪里错了？请帮忙。提前谢谢。
import java.awt.BasicStroke;
import java.awt.Button;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Label;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Rectangle2D;
import javax.swing.GroupLayout;
import javax.swing.JApplet;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartMouseEvent;
import org.jfree.chart.ChartMouseListener;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.annotations.XYLineAnnotation;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.event.ChartChangeEvent;
import org.jfree.chart.event.ChartChangeListener;
import org.jfree.chart.panel.CrosshairOverlay;
import org.jfree.chart.plot.Crosshair;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.data.general.DatasetUtilities;
import org.jfree.data.xy.XYDataset;
import org.jfree.data.xy.XYSeriesCollection;
import org.jfree.ui.RectangleEdge;
public class DisplayPanel extends JApplet implements ActionListener
{
/**
*
*/
private static final long serialVersionUID = 1L;
SimplePortComm spc;
JFreeChart xylineChart;
ChartPanel panel;
XYSeriesCollection dataset;
public static String sLLD;
public static String sULD;
Label lblTitle;
Label lblMax, lblMin, lblULD, lblLLD;
TextField txtMax, txtMin, txtULD, txtLLD;
Label lblInrangeCount;
TextField txtInrangeCount;
Button bAquire, bSave, bLoad, bQuit;
int i, nInRangeChannels;
private Crosshair xCrosshair;
private Crosshair yCrosshair;
double dULD,dLLD;
public DisplayPanel() {
dataset = new XYSeriesCollection();
spc = new SimplePortComm();
lblTitle = new Label("Data Aquisition System for MCA");
lblTitle.setPreferredSize(new Dimension(600, 20));
lblMax = new Label("Max:");
lblMin = new Label("Min:");
lblULD = new Label("ULD:");
lblLLD = new Label("LLD:");
lblInrangeCount = new Label("Count in Range:");
lblInrangeCount.setPreferredSize(new Dimension(60, 20));
txtMax = new TextField(10);
txtMax.setEditable(false);
txtMin = new TextField(10);
txtMin.setEditable(false);
txtULD = new TextField(10);
txtULD.setText("240.0");
txtLLD = new TextField(10);
txtLLD.setText("20.0");
txtInrangeCount = new TextField(10);
txtInrangeCount.setPreferredSize(new Dimension(60, 20));
txtInrangeCount.setEditable(false);
dULD = Double.parseDouble(txtULD.getText());
dLLD = Double.parseDouble(txtLLD.getText());
drawChart();
bAquire = new Button("Aquire");
bAquire.setPreferredSize(new Dimension(20, 60));
bAquire.addActionListener(
new ActionListener() {
@Override
public void actionPerformed(ActionEvent aquire) {
//panel.setRefreshBuffer(true);
System.setSecurityManager(null);// with out this statement, set_ports() throws null pointer exception
spc.set_ports(dULD, dLLD);
dataset = SimplePortComm.dataset;
panel.repaint();
panel.updateUI();
System.out.print("Button: Aquire");
}
}
);
bSave = new Button("Save");
bSave.setPreferredSize(null);
bSave.addActionListener(
new ActionListener() {
@Override
public void actionPerformed(ActionEvent save) {
System.out.print("Button: Save");
}
}
);
bLoad = new Button("Load");
bLoad.setPreferredSize(null);
bLoad.addActionListener(
new ActionListener() {
@Override
public void actionPerformed(ActionEvent load) {
System.out.print("Button: Load");
sLLD = txtLLD.getText();
sULD = txtULD.getText();
txtInrangeCount.setText(Integer.toString(spc.getInRangeChannels()));
}
}
);
bQuit = new Button("Quit");
bQuit.setPreferredSize(new Dimension(10, 10));
bQuit.addActionListener(new ActionListener()
{
@Override
public void actionPerformed(ActionEvent quit) {
System.out.print("Button: Quit");
System.exit(0);
}
});
GroupLayout layout = new GroupLayout(getContentPane());
layout.setAutoCreateGaps(true);
layout.setAutoCreateContainerGaps(true);
layout.setHorizontalGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)
.addComponent(lblTitle)
.addComponent(panel)
.addGroup(layout.createSequentialGroup()
.addComponent(bAquire)
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)
.addComponent(lblMax)
.addComponent(lblMin))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)
.addComponent(txtMax)
.addComponent(txtMin))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)
.addComponent(lblULD)
.addComponent(lblLLD))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)
.addComponent(txtULD)
.addComponent(txtLLD)))
.addGroup(layout.createSequentialGroup()
.addComponent(lblInrangeCount)
.addComponent(txtInrangeCount))
.addGroup(layout.createSequentialGroup()
.addComponent(bSave)
.addComponent(bLoad)
.addComponent(bQuit))
);
layout.setVerticalGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addGroup(layout.createSequentialGroup()
.addComponent(lblTitle)))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addGroup(layout.createSequentialGroup()
.addComponent(panel)))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addComponent(bAquire))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addComponent(lblMax)
.addComponent(txtMax)
.addComponent(lblULD)
.addComponent(txtULD))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addComponent(lblMin)
.addComponent(txtMin)
.addComponent(lblLLD)
.addComponent(txtLLD))))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addComponent(lblInrangeCount)
.addComponent(txtInrangeCount))
.addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addComponent(bSave)
.addComponent(bLoad)
.addComponent(bQuit))
);
getContentPane().setLayout(layout);
getContentPane().setEnabled(true);
getContentPane().setSize(1500, 1500);
}
public void drawChart()
{
System.setSecurityManager(null);// with out this statement, set_ports() throws null pointer exception
spc.set_ports(dULD, dLLD);
dataset = SimplePortComm.dataset;
xylineChart = ChartFactory.createXYLineChart(
"Data Aquired" ,
"Time" ,
"Amplitude" ,
dataset ,
PlotOrientation.VERTICAL ,
true , true , false);
panel = new ChartPanel(xylineChart, 650, 450, 180, 180, 800, 600, false, true, false, false, false, false);
//panel.setRefreshBuffer(true);
CrosshairOverlay crosshairOverlay = new CrosshairOverlay();
this.xCrosshair = new Crosshair(Double.NaN, Color.BLACK,
new BasicStroke(0f));
this.xCrosshair.setLabelVisible(true);
this.yCrosshair = new Crosshair(Double.NaN, Color.BLACK,
new BasicStroke(0f));
this.yCrosshair.setLabelVisible(true);
crosshairOverlay.addDomainCrosshair(xCrosshair);
crosshairOverlay.addRangeCrosshair(yCrosshair);
panel.addOverlay(crosshairOverlay);
panel.addChartMouseListener(new ChartMouseListener() {
@Override
public void chartMouseMoved(ChartMouseEvent event) {
Rectangle2D dataArea = panel.getScreenDataArea();
JFreeChart chart = event.getChart();
XYPlot plot = (XYPlot) chart.getPlot();
ValueAxis xAxis = plot.getDomainAxis();
double x = xAxis.java2DToValue(event.getTrigger().getX(), dataArea,
RectangleEdge.BOTTOM);
// make the crosshairs disappear if the mouse is out of range
if (!xAxis.getRange().contains(x)) {
x = Double.NaN;
}
double y = DatasetUtilities.findYValue(plot.getDataset(), 0, x);
xCrosshair.setValue(x);
yCrosshair.setValue(y);
}
@Override
public void chartMouseClicked(ChartMouseEvent event) {
Rectangle2D dataArea = panel.getScreenDataArea();
System.out.println("Mouse clicked on the graph");
XYPlot plot = (XYPlot) xylineChart.getPlot();
ValueAxis xAxis = plot.getDomainAxis();
double x = xAxis.java2DToValue(event.getTrigger().getX(), dataArea,
RectangleEdge.BOTTOM);
// make the crosshairs disappear if the mouse is out of range
if (!xAxis.getRange().contains(x)) {
x = Double.NaN;
}
double y = DatasetUtilities.findYValue(plot.getDataset(), 0, x);
System.out.println("Graph click: " + x + ":" + y);
xCrosshair.setValue(x);
yCrosshair.setValue(y);
XYItemRenderer renderer = plot.getRenderer();
renderer.removeAnnotations();
XYLineAnnotation mark = new XYLineAnnotation(x,0,x,250, new BasicStroke(), Color.BLACK);
renderer.addAnnotation(mark);
XYLineAnnotation low = new XYLineAnnotation(0.0f,dULD,400f,dULD, new BasicStroke(), Color.BLUE);
renderer.addAnnotation(low);
low.setToolTipText("low");
XYLineAnnotation high = new XYLineAnnotation(0.0f,dLLD,400f,dLLD, new BasicStroke(), Color.MAGENTA);
renderer.addAnnotation(high);
high.setToolTipText("high");
plot.setRenderer(renderer);
}
});
}
public void init()
{
setBackground(Color.WHITE);
System.setSecurityManager(null);
spc = new SimplePortComm();
}
public static void main(String args[])
{
DisplayPanel ds = new DisplayPanel();
}
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
}
}
答案 0 :(得分：1)
我不知道SimplePortComm的工作原理，但您的ActionListener正在替换用于创建图表的dataset。它是第一次工作，因为原始数据集是xylineChart正在监听的数据集;图表不知道新的dataset。您可以使用plot.setDataset(dataset);
您的ActionListener也阻止了event dispatch thread，因此您可能希望使用SwingWorker，就像他们展示here一样。