更改nimbus LaF中JComboBox的ArrowButton的前景色

Question

我想为特定状态更改JComboBox的ArrowButton的前景色。 我尝试使用绘画工具覆盖默认键值。 但它不起作用。 这是我的代码

UIManager.getLookAndFeelDefaults().put("ComboBox:\"ComboBox.arrowButton\[Enabled].foregroundPainter", new ArrowPainter(new Color(255,255,255)));
UIManager.getLookAndFeelDefaults().put("ComboBox:\"ComboBox.arrowButton\"[MouseOver].foregroundPainter", new ArrowPainter(new Color(255,255,255)));

有人可以帮我改变颜色吗？

这是我的ArrowPainter课

public class ArrowPainter implements Painter {
        private float leftWidth;

        private float topHeight;

        private float centerWidth;

        private float centerHeight;

        private float rightWidth;

        private float bottomHeight;

        private float leftScale;

        private float topScale;

        private float centerHScale;

        private float centerVScale;

        private float rightScale;

        private float bottomScale;

        private Color new_color;
         private Path2D path = new Path2D.Float();
         private Object[] componentColors;
         public ArrowPainter(Color new_color)
         {
             this.new_color = new_color;
         }
         @Override
            public void paint(Graphics2D g, Object c, int width, int height) {
                // TODO Auto-generated method stub
                paintForegroundEnabled(g);
            }
         public void paintForegroundEnabled(Graphics2D g) {
                path = decodePath5();
                g.setPaint(decodeGradient9(path));
                g.fill(path);

            }
        private Paint decodeGradient9(Shape s) {
            // TODO Auto-generated method stub

             Rectangle2D bounds = s.getBounds2D();
                float x = (float)bounds.getX();
                float y = (float)bounds.getY();
                float w = (float)bounds.getWidth();
                float h = (float)bounds.getHeight();
                return decodeGradient((1.0f * w) + x, (0.5f * h) + y, (0.0f * w) + x, (0.5f * h) + y,
                        new float[] { 0.0f,0.5f,1.0f },
                        new Color[] { new_color,
                                    decodeColor(new_color,new_color,0.5f),
                                    new_color});
        }
        private Color decodeColor(Color color1, Color color2,
                float midPoint) {
            // TODO Auto-generated method stub
             return new Color(deriveARGB(color1, color2, midPoint));
        }
        private int deriveARGB(Color color1, Color color2, float midPoint) {
            // TODO Auto-generated method stub
             int r = color1.getRed() +
                        Math.round((color2.getRed() - color1.getRed()) * midPoint);
                int g = color1.getGreen() +
                        Math.round((color2.getGreen() - color1.getGreen()) * midPoint);
                int b = color1.getBlue() +
                        Math.round((color2.getBlue() - color1.getBlue()) * midPoint);
                int a = color1.getAlpha() +
                        Math.round((color2.getAlpha() - color1.getAlpha()) * midPoint);
                return ((a & 0xFF) << 24) |
                        ((r & 0xFF) << 16) |
                        ((g & 0xFF) << 8) |
                        (b & 0xFF);
        }
        private Paint decodeGradient(float x1, float y1, float x2, float y2, float[] midpoints, Color[] colors) {
            // TODO Auto-generated method stub
            if (x1 == x2 && y1 == y2) {
                y2 += .00001f;
            }
            return new LinearGradientPaint(x1, y1, x2, y2, midpoints, colors);
        }
        private double decodeY(float y) {
            // TODO Auto-generated method stub
             if (y >= 0 && y <= 1) {
                    return y * topHeight;
                } else if (y > 1 && y < 2) {
                    return ((y-1) * centerHeight) + topHeight;
                } else if (y >= 2 && y <= 3) {
                    return ((y-2) * bottomHeight) + topHeight + centerHeight;
                } else {
                    throw new IllegalArgumentException("Invalid y");
                }
        }
        private double decodeX(float x) {
            // TODO Auto-generated method stub
             if (x >= 0 && x <= 1) {
                    return x * leftWidth;
                } else if (x > 1 && x < 2) {
                    return ((x-1) * centerWidth) + leftWidth;
                } else if (x >= 2 && x <= 3) {
                    return ((x-2) * rightWidth) + leftWidth + centerWidth;
                } else {
                    throw new IllegalArgumentException("Invalid x");
                }
        }
        private Path2D decodePath5() {
            // TODO Auto-generated method stub
            path.reset();
            path.moveTo(decodeX(0.9995915f), decodeY(1.3616071f));
            path.lineTo(decodeX(2.0f), decodeY(0.8333333f));
            path.lineTo(decodeX(2.0f), decodeY(1.8571429f));
            path.lineTo(decodeX(0.9995915f), decodeY(1.3616071f));
            path.closePath();
            return path;
        }

    }

Answer 1

您尝试使用的UIManager方法仅适用于Nimbus外观。 此处的更多信息： http : //docs.oracle.com/javase/tutorial/uiswing/lookandfeel/_nimbusDefaults.html

问题是您没有在任何地方设置Nimbus的外观。

该代码对我有用 ，还请注意，这是一个MCVE，而不是带有无关方法的整个项目：

import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics2D;
import java.lang.reflect.InvocationTargetException;

import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.Painter;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UIManager.LookAndFeelInfo;


public class Test {
    public static void main (String [] args) throws InvocationTargetException, InterruptedException{

        SwingUtilities.invokeAndWait(new Runnable(){
            public void run(){


                try {
                    for (LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
                        if ("Nimbus".equals(info.getName())) {
                            UIManager.setLookAndFeel(info.getClassName());
                            break;
                        }
                    }
                } catch (Exception e) {
                    // If Nimbus is not available, you can set the GUI to another look and feel.
                }

                 UIManager.getLookAndFeelDefaults().put("ComboBox:\"ComboBox.arrowButton\"[Enabled].foregroundPainter", new MyPainter());
                 UIManager.getLookAndFeelDefaults().put("ComboBox:\"ComboBox.arrowButton\"[MouseOver].foregroundPainter", new MyPainter());


                 JComboBox comboBox = new JComboBox();
                 comboBox.addItem("one");
                 comboBox.addItem("two");
                 comboBox.addItem("three");


                 JFrame frame = new JFrame();
                 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                 frame.add(comboBox);
                 frame.setSize(300, 300);
                 frame.setVisible(true);
            }
        });
    }

    public static class MyPainter implements Painter<Component>{

        @Override
        public void paint(Graphics2D g, Component object, int width, int height){
            g.setColor(Color.RED);
            g.fillRect(0, 0, width, height);
        }
    }
}