如何使用 JFreeChart动态更新图表的外观使其可见？

最佳答案

类(class)ChartPanel这样做很方便，因为它具有控制图表整体外观的方法，包括属性和缩放状态。此外，还可以访问图表的组件，如下所示。这个相关example说明了缩放按钮的 JToolBar。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.NumberFormat;
import javax.swing.AbstractAction;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.DateAxis;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.data.time.Year;
import org.jfree.data.xy.XYDataset;

/** @see http://stackoverflow.com/questions/5522575 */
public class ChartPanelDemo {

    private static final String title = "Return On Investment";
    private ChartPanel chartPanel = createChart();

    public ChartPanelDemo() {
        JFrame f = new JFrame(title);
        f.setTitle(title);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setLayout(new BorderLayout(0, 5));
        f.add(chartPanel, BorderLayout.CENTER);
        chartPanel.setMouseWheelEnabled(true);
        chartPanel.setHorizontalAxisTrace(true);
        chartPanel.setVerticalAxisTrace(true);

        JPanel panel = new JPanel(new FlowLayout(FlowLayout.RIGHT));
        panel.add(createTrace());
        panel.add(createDate());
        panel.add(createZoom());
        f.add(panel, BorderLayout.SOUTH);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    private JComboBox createTrace() {
        final JComboBox trace = new JComboBox();
        final String[] traceCmds = {"Enable Trace", "Disable Trace"};
        trace.setModel(new DefaultComboBoxModel(traceCmds));
        trace.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                if (traceCmds[0].equals(trace.getSelectedItem())) {
                    chartPanel.setHorizontalAxisTrace(true);
                    chartPanel.setVerticalAxisTrace(true);
                    chartPanel.repaint();
                } else {
                    chartPanel.setHorizontalAxisTrace(false);
                    chartPanel.setVerticalAxisTrace(false);
                    chartPanel.repaint();
                }
            }
        });
        return trace;
    }

    private JComboBox createDate() {
        final JComboBox date = new JComboBox();
        final String[] dateCmds = {"Horizontal Dates", "Vertical Dates"};
        date.setModel(new DefaultComboBoxModel(dateCmds));
        date.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                JFreeChart chart = chartPanel.getChart();
                XYPlot plot = (XYPlot) chart.getPlot();
                DateAxis domain = (DateAxis) plot.getDomainAxis();
                if (dateCmds[0].equals(date.getSelectedItem())) {
                    domain.setVerticalTickLabels(false);
                } else {
                    domain.setVerticalTickLabels(true);
                }
            }
        });
        return date;
    }

    private JButton createZoom() {
        final JButton auto = new JButton(new AbstractAction("Auto Zoom") {

            @Override
            public void actionPerformed(ActionEvent e) {
                chartPanel.restoreAutoBounds();
            }
        });
        return auto;
    }

    private ChartPanel createChart() {
        XYDataset roiData = createDataset();
        JFreeChart chart = ChartFactory.createTimeSeriesChart(
            title, "Date", "Value", roiData, true, true, false);
        XYPlot plot = chart.getXYPlot();
        XYLineAndShapeRenderer renderer =
            (XYLineAndShapeRenderer) plot.getRenderer();
        renderer.setBaseShapesVisible(true);
        NumberFormat currency = NumberFormat.getCurrencyInstance();
        currency.setMaximumFractionDigits(0);
        NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
        rangeAxis.setNumberFormatOverride(currency);
        return new ChartPanel(chart);
    }

    private XYDataset createDataset() {
        TimeSeriesCollection tsc = new TimeSeriesCollection();
        tsc.addSeries(createSeries("Projected", 200));
        tsc.addSeries(createSeries("Actual", 100));
        return tsc;
    }

    private TimeSeries createSeries(String name, double scale) {
        TimeSeries series = new TimeSeries(name);
        for (int i = 0; i < 6; i++) {
            series.add(new Year(2005 + i), Math.pow(2, i) * scale);
        }
        return series;
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                ChartPanelDemo cpd = new ChartPanelDemo();
            }
        });
    }
}

关于java - 如何在 JFreeChart 可见后更新它的外观？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/5522575/