JScrollPane 自定义滚动条宽度及样式

JAVA Swing 自定义滚动条样式

1、新建自定义BasicScrollBarUI类

package com.swing.view;import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GradientPaint;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JScrollBar;
import javax.swing.plaf.basic.BasicScrollBarUI;//自定义滚动条UI
public class DemoScrollBarUI extends BasicScrollBarUI {@Overrideprotected void configureScrollBarColors() {// 把手// thumbColor = Color.GRAY;// thumbHighlightColor = Color.BLUE;// thumbDarkShadowColor = Color.BLACK;// thumbLightShadowColor = Color.YELLOW;// 滑道trackColor = Color.black;setThumbBounds(0, 0, 3, 10);// trackHighlightColor = Color.GREEN;}/*** 设置滚动条的宽度*/@Overridepublic Dimension getPreferredSize(JComponent c) {// TODO Auto-generated method stubc.setPreferredSize(new Dimension(30, 0));return super.getPreferredSize(c);}// 重绘滑块的滑动区域背景public void paintTrack(Graphics g, JComponent c, Rectangle trackBounds) {Graphics2D g2 = (Graphics2D) g;GradientPaint gp = null;//判断滚动条是垂直的 还是水平的if (this.scrollbar.getOrientation() == JScrollBar.VERTICAL) {//设置画笔gp = new GradientPaint(0, 0, new Color(80, 80, 80),trackBounds.width, 0, new Color(80, 80, 80));}if (this.scrollbar.getOrientation() == JScrollBar.HORIZONTAL) {gp = new GradientPaint(0, 0, new Color(80, 80, 80),trackBounds.height, 0, new Color(80, 80, 80));}g2.setPaint(gp);//填充Trackg2.fillRect(trackBounds.x, trackBounds.y, trackBounds.width,trackBounds.height);//绘制Track的边框/*       g2.setColor(new Color(175, 155, 95));g2.drawRect(trackBounds.x, trackBounds.y, trackBounds.width - 1,trackBounds.height - 1);*/if (trackHighlight == BasicScrollBarUI.DECREASE_HIGHLIGHT)this.paintDecreaseHighlight(g);if (trackHighlight == BasicScrollBarUI.INCREASE_HIGHLIGHT)this.paintIncreaseHighlight(g);}@Overrideprotected void paintThumb(Graphics g, JComponent c, Rectangle thumbBounds) {// 把绘制区的x，y点坐标定义为坐标系的原点// 这句一定一定要加上啊，不然拖动就失效了g.translate(thumbBounds.x, thumbBounds.y);// 设置把手颜色g.setColor(new Color(   230,230,250));// 画一个圆角矩形// 这里面前四个参数就不多讲了，坐标和宽高// 后两个参数需要注意一下，是用来控制角落的圆角弧度// g.drawRoundRect(0, 0, 5, thumbBounds.height - 1, 5, 5);// 消除锯齿Graphics2D g2 = (Graphics2D) g;RenderingHints rh = new RenderingHints(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);g2.addRenderingHints(rh);// 半透明g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER,0.5f));// 设置填充颜色，这里设置了渐变，由下往上// g2.setPaint(new GradientPaint(c.getWidth() / 2, 1, Color.GRAY,// c.getWidth() / 2, c.getHeight(), Color.GRAY));// 填充圆角矩形g2.fillRoundRect(0, 0, 40, thumbBounds.height - 1, 5, 5);}/*** 创建滚动条上方的按钮*/@Overrideprotected JButton createIncreaseButton(int orientation) {JButton button = new JButton();button.setBorderPainted(false);button.setContentAreaFilled(false);button.setBorder(null);return button;}/*** 创建滚动条下方的按钮*/@Overrideprotected JButton createDecreaseButton(int orientation) {JButton button = new JButton();button.setBorderPainted(false);button.setContentAreaFilled(false);button.setFocusable(false);button.setBorder(null);return button;}}

2、使用自定义类,覆盖JScrollPane滚动条样式

lqwwcScrollPane = new JScrollPane();
lqwwcScrollPane.getVerticalScrollBar().setUI(new DemoScrollBarUI());

效果图：