动态更改 JFreeChart 直方图颜色？
nck*_*nck 5 java swing colors jfreechart histogram
我正在尝试显示图像的直方图并仅显示一些颜色。我已经用 JFreeChart 和 createXYLineChart 做到了这一点，并通过遍历所有像素来获取所有数据。
为了加快速度，我正在尝试使用“createHistogram”来实现。我遵循了这个代码。
要使用新值更新图表，我使用了这两种方法：
XYPlot plot = (XYPlot) chart.getPlot();
plot.setDataset(setHistogram(red, green, blue));
作为 setHistogram 一个返回 HistogramDataset 的方法取决于哪个复选框被激活（布尔红色、绿色和蓝色）。
这按预期正常工作。
当我这样做时，我必须做的第二件事是更新每个系列的颜色，否则它们将获得默认值。我按照与值大致相同的程序进行了操作：
private void setHistogramColors(boolean red, boolean green, boolean blue) {
XYPlot plot = (XYPlot) chart.getPlot();
XYBarRenderer renderer = (XYBarRenderer) plot.getRenderer();
renderer.setBarPainter(new StandardXYBarPainter());
Paint[] paintArray = null;
if (red) {
if (green) {
if (blue) {
paintArray = new Paint[3];
paintArray[0] = new Color(0x80ff0000, true);// translucent red, green & blue
paintArray[1] = new Color(0x8000ff00, true);
paintArray[2] = new Color(0x800000ff, true);
} else {
paintArray = new Paint[2];
paintArray[0] = new Color(0x80ff0000, true);
paintArray[1] = new Color(0x8000ff00, true);
}
} else {
paintArray = new Paint[1];
paintArray[0] = new Color(0x80ff0000, true);
}
} else if (green) {
if (blue) {
paintArray = new Paint[2];
paintArray[0] = new Color(0x8000ff00, true);
paintArray[1] = new Color(0x800000ff, true);
} else {
paintArray = new Paint[1];
paintArray[0] = new Color(0x8000ff00, true);
}
} else if (blue){
paintArray = new Paint[1];
paintArray[0] = new Color(0x800000ff, true);
}
else {
return;
}
plot.setDrawingSupplier(new DefaultDrawingSupplier(
paintArray,
DefaultDrawingSupplier.DEFAULT_FILL_PAINT_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_OUTLINE_PAINT_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_STROKE_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_OUTLINE_STROKE_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_SHAPE_SEQUENCE));
}
但是就我所见，这仅在我第一次绘制代码时才有效，并且不同系列的下一个图将采用相同的颜色。这是一个例子，RGB 是它们应该是的颜色：[![2]](https://i.stack.imgur.com/AqugL.png)
当我用红色更新时，绿色直方图变为绿色直方图，绿色变为蓝色直方图：
有没有什么办法解决这一问题？
根据您的片段和此评论，您似乎正在尝试通过在复选框处理程序中从数据集中添加和删除系列来更改显示。不要更改模型，而是更改视图中系列的可见性。在这种情况下，你可以给每个复选框合适的Action，如这里及以下。特别注意，VisibleAction使用与自定义中相应颜色匹配的系列索引DrawingSupplier。
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Paint;
import java.awt.event.ActionEvent;
import java.awt.image.BufferedImage;
import java.awt.image.Raster;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.AbstractAction;
import javax.swing.ImageIcon;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.DefaultDrawingSupplier;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.StandardXYBarPainter;
import org.jfree.chart.renderer.xy.XYBarRenderer;
import org.jfree.data.statistics.HistogramDataset;
/**
* @see /sf/ask/2837609491/
* @see /sf/ask/830929151/
* @see /sf/answers/1996354951/
*/
public class Histogram {
private static final int BINS = 256;
private final BufferedImage image = getImage();
private HistogramDataset dataset;
private XYBarRenderer renderer;
private BufferedImage getImage() {
try {
return ImageIO.read(new URL(
"http://i.imgur.com/kxXhIH1.jpg"));
} catch (IOException e) {
e.printStackTrace(System.err);
}
return null;
}
private ChartPanel createChartPanel() {
// dataset
dataset = new HistogramDataset();
Raster raster = image.getRaster();
final int w = image.getWidth();
final int h = image.getHeight();
double[] r = new double[w * h];
r = raster.getSamples(0, 0, w, h, 0, r);
dataset.addSeries("Red", r, BINS);
r = raster.getSamples(0, 0, w, h, 1, r);
dataset.addSeries("Green", r, BINS);
r = raster.getSamples(0, 0, w, h, 2, r);
dataset.addSeries("Blue", r, BINS);
// chart
JFreeChart chart = ChartFactory.createHistogram("Histogram", "Value",
"Count", dataset, PlotOrientation.VERTICAL, true, true, false);
XYPlot plot = (XYPlot) chart.getPlot();
renderer = (XYBarRenderer) plot.getRenderer();
renderer.setBarPainter(new StandardXYBarPainter());
// translucent red, green & blue
Paint[] paintArray = {
new Color(0x80ff0000, true),
new Color(0x8000ff00, true),
new Color(0x800000ff, true)
};
plot.setDrawingSupplier(new DefaultDrawingSupplier(
paintArray,
DefaultDrawingSupplier.DEFAULT_FILL_PAINT_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_OUTLINE_PAINT_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_STROKE_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_OUTLINE_STROKE_SEQUENCE,
DefaultDrawingSupplier.DEFAULT_SHAPE_SEQUENCE));
ChartPanel panel = new ChartPanel(chart);
panel.setMouseWheelEnabled(true);
return panel;
}
private JPanel createControlPanel() {
JPanel panel = new JPanel();
panel.add(new JCheckBox(new VisibleAction(0)));
panel.add(new JCheckBox(new VisibleAction(1)));
panel.add(new JCheckBox(new VisibleAction(2)));
return panel;
}
private class VisibleAction extends AbstractAction {
private final int i;
public VisibleAction(int i) {
this.i = i;
this.putValue(NAME, (String) dataset.getSeriesKey(i));
this.putValue(SELECTED_KEY, true);
renderer.setSeriesVisible(i, true);
}
@Override
public void actionPerformed(ActionEvent e) {
renderer.setSeriesVisible(i, !renderer.getSeriesVisible(i));
}
}
private void display() {
JFrame f = new JFrame("Histogram");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(createChartPanel());
f.add(createControlPanel(), BorderLayout.SOUTH);
f.add(new JLabel(new ImageIcon(image)), BorderLayout.WEST);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
new Histogram().display();
});
}
}