具有半透明重叠条的 JFreeChart

Question

我想使用 JFreeChart 创建一个条形图，如下所示：

http://desk.stinkpot.org:8080/tricks/index.php/2006/07/how-to-make-a-transparent-histogram-in-matlab/

条形是半透明的并且重叠。我尝试使用 DefaultCategoryDataset，但它绘制了我不想要的彼此相邻的条。我知道如何使条形图半透明，我只希望条形图重叠。有没有简单的方法可以做到这一点？

更新：使用 trashgod 的回答，我已经设法完成了它。这是代码，以防有人感兴趣：

import java.awt.*;
import java.util.*;
import javax.swing.*;
import org.jfree.chart.*;
import org.jfree.chart.plot.*;
import org.jfree.chart.renderer.xy.*;
import org.jfree.data.statistics.*;

public class Histograph {

    public static void main(String[] args) {
        Random generator = new Random();
        HistogramDataset dataset = new HistogramDataset();
        double[] d1 = new double[100];
        double[] d2 = new double[100];
        double[] d3 = new double[100];
        for (int i = 1; i < 100; i++) {
            d1[i] = generator.nextInt(10);
            d2[i] = generator.nextInt(10);
            d3[i] = generator.nextInt(10);
        }
        dataset.addSeries("s1", d1, 10);
        dataset.addSeries("s2", d2, 10);
        dataset.addSeries("s3", d3, 10);
        JFreeChart chart = ChartFactory.createHistogram("Histogram", "x", "y",
                dataset, PlotOrientation.VERTICAL, false, false, false);
        XYPlot plot = (XYPlot)chart.getPlot();
        plot.setBackgroundPaint(Color.white);
        XYBarRenderer renderer = (XYBarRenderer)plot.getRenderer();
        renderer.setBarPainter(new StandardXYBarPainter());
        renderer.setShadowVisible(false);
        renderer.setSeriesPaint(0, new Color(1, 0, 0, 0.5f));
        renderer.setSeriesPaint(1, new Color(0, 1, 0, 0.5f));
        renderer.setSeriesPaint(2, new Color(0, 0, 1, 0.5f));
        JFrame f = new JFrame("Histogram");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(new ChartPanel(chart));
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }
}

Answer 1

如果您使用的是BarRenderer, specify a negative value to setItemMargin(), as shown here。 -50 的值如下所示：

或者，考虑 ChartFactory.createHistogram(), which uses an XYBarRenderer with adjacent bars, as shown and 。

具有半透明重叠条的 JFreeChart

JFreeChart with semitransparent overlapping bars

java

charts

jfreechart