改變JSlider的外觀

Question

我瀏覽了這個網站， 改變了JSlider外觀，但是除了Slider.altTrackColor之外， Slider.altTrackColor任何方法都Slider.altTrackColor正常工作。 我想做如圖1所示的操作，任何建議都會有很大幫助。 我正在開發JDK 1.6。

UIDefaults defaults = UIManager.getDefaults();    

       defaults.put("Slider.altTrackColor", Color.red);
       defaults.put("Slider.thumb", Color.red);

我也嘗試過這個：

    WindowUtilities.setNativeLookAndFeel();

 // WindowUtilities.setNimbuzzLookAndFeel();

 // WindowUtilities.setJavaLookAndFeel();

與以前的版本一樣，WindowUtilities是一個類，它告訴系統使用本機的外觀。 否則，默認為Metal（Java）LAF。

public static void setNativeLookAndFeel() {
try {
  UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch(Exception e) {
  System.out.println("Error setting native LAF: " + e);
}

Answer 1

這是第一個圖像上顯示的工作UI的完整示例：
（沒有魔力-只需一點圖形和基本的UI知識即可工作）

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Stroke;
import java.awt.geom.GeneralPath;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JSlider;
import javax.swing.SwingConstants;
import javax.swing.plaf.basic.BasicSliderUI;

/**
 *
 * @see http://stackoverflow.com/a/12297384/714968
 */
public class CustomSliderUI extends BasicSliderUI {

    private BasicStroke stroke = new BasicStroke(1f, BasicStroke.CAP_ROUND, 
            BasicStroke.JOIN_ROUND, 0f, new float[]{1f, 2f}, 0f);

    public CustomSliderUI(JSlider b) {
        super(b);
    }

    @Override
    public void paint(Graphics g, JComponent c) {
        Graphics2D g2d = (Graphics2D) g;
        g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, 
                RenderingHints.VALUE_ANTIALIAS_ON);
        super.paint(g, c);
    }

    @Override
    protected Dimension getThumbSize() {
        return new Dimension(12, 16);
    }

    @Override
    public void paintTrack(Graphics g) {
        Graphics2D g2d = (Graphics2D) g;
        Stroke old = g2d.getStroke();
        g2d.setStroke(stroke);
        g2d.setPaint(Color.BLACK);
        if (slider.getOrientation() == SwingConstants.HORIZONTAL) {
            g2d.drawLine(trackRect.x, trackRect.y + trackRect.height / 2, 
                    trackRect.x + trackRect.width, trackRect.y + trackRect.height / 2);
        } else {
            g2d.drawLine(trackRect.x + trackRect.width / 2, trackRect.y, 
                    trackRect.x + trackRect.width / 2, trackRect.y + trackRect.height);
        }
        g2d.setStroke(old);
    }

    @Override
    public void paintThumb(Graphics g) {
        Graphics2D g2d = (Graphics2D) g;
        int x1 = thumbRect.x + 2;
        int x2 = thumbRect.x + thumbRect.width - 2;
        int width = thumbRect.width - 4;
        int topY = thumbRect.y + thumbRect.height / 2 - thumbRect.width / 3;
        GeneralPath shape = new GeneralPath(GeneralPath.WIND_EVEN_ODD);
        shape.moveTo(x1, topY);
        shape.lineTo(x2, topY);
        shape.lineTo((x1 + x2) / 2, topY + width);
        shape.closePath();
        g2d.setPaint(new Color(81, 83, 186));
        g2d.fill(shape);
        Stroke old = g2d.getStroke();
        g2d.setStroke(new BasicStroke(2f));
        g2d.setPaint(new Color(131, 127, 211));
        g2d.draw(shape);
        g2d.setStroke(old);
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame();
        JSlider slider = new JSlider(0, 100);
        slider.setPaintTicks(true);
        slider.setPaintLabels(true);
        slider.setMinorTickSpacing(5);
        slider.setMajorTickSpacing(25);
        slider.setUI(new CustomSliderUI(slider));
        frame.add(slider);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);
    }
}

您可以通過更改返回的邊界輕松地修改拇指（夾爪）的大小。 拇指畫將適應任何大小。 而且，您還可以輕松自定義任何其他滑塊零件的繪畫。

順便說一下，這是最終視圖：

附言：我沒有將UI用於垂直滑塊，但這應該不會花費太長時間。