Java JScrollBar设计
我想自定义JScrollBar设计。 我用Mac用eclipse开发应用程序。 我已经尝试过scrollPane.getVerticalScrollBar().setBackground(Color.BLACK); 但什么都没发生。
我的代码：
scrollPane = new JScrollPane(scriptView); scrollPane.setBorder(BorderFactory.createEmptyBorder()); scrollPane.getVerticalScrollBar().setUnitIncrement(6); window.getContentPane().add(scrollPane);
Object scriptView来自JEditorPane类。
应该如何看待：
谢谢你的帮助。
我想你正在寻找一个透明的滚动条。
这只是一个想法（未经过测试的代码）：
import java.awt.*; import javax.swing.*; import javax.swing.border.*; import javax.swing.plaf.basic.*; public class TranslucentScrollBarTest { public JComponent makeUI() { JTextArea cmp = new JTextArea(); String str = "1234567890abcdefghijklmnopqrstuvwxyz"; for(int i=0; i<20; i++) { cmp.append(str+str+"\n"); } cmp.setForeground(Color.WHITE); cmp.setBackground(Color.BLACK); cmp.setOpaque(true); JScrollPane scrollPane = new JScrollPane( cmp, ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER); scrollPane.setComponentZOrder(scrollPane.getVerticalScrollBar(), 0); scrollPane.setComponentZOrder(scrollPane.getViewport(), 1); scrollPane.getVerticalScrollBar().setOpaque(false); scrollPane.setLayout(new ScrollPaneLayout() { @Override public void layoutContainer(Container parent) { JScrollPane scrollPane = (JScrollPane)parent; Rectangle availR = scrollPane.getBounds(); availR.x = availR.y = 0; Insets insets = parent.getInsets(); availR.x = insets.left; availR.y = insets.top; availR.width -= insets.left + insets.right; availR.height -= insets.top + insets.bottom; Rectangle vsbR = new Rectangle(); vsbR.width = 12; vsbR.height = availR.height; vsbR.x = availR.x + availR.width - vsbR.width; vsbR.y = availR.y; if(viewport != null) { viewport.setBounds(availR); } if(vsb != null) { vsb.setVisible(true); vsb.setBounds(vsbR); } } }); scrollPane.getVerticalScrollBar().setUI(new BasicScrollBarUI() { private final Dimension d = new Dimension(); @Override protected JButton createDecreaseButton(int orientation) { return new JButton() { @Override public Dimension getPreferredSize() { return d; } }; } @Override protected JButton createIncreaseButton(int orientation) { return new JButton() { @Override public Dimension getPreferredSize() { return d; } }; } @Override protected void paintTrack(Graphics g, JComponent c, Rectangle r) {} @Override protected void paintThumb(Graphics g, JComponent c, Rectangle r) { Graphics2D g2 = (Graphics2D)g.create(); g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); Color color = null; JScrollBar sb = (JScrollBar)c; if(!sb.isEnabled() || r.width>r.height) { return; }else if(isDragging) { color = new Color(200,200,100,200); }else if(isThumbRollover()) { color = new Color(255,255,100,200); }else { color = new Color(220,220,200,200); } g2.setPaint(color); g2.fillRoundRect(rx,ry,r.width,r.height,10,10); g2.setPaint(Color.WHITE); g2.drawRoundRect(rx,ry,r.width,r.height,10,10); g2.dispose(); } @Override protected void setThumbBounds(int x, int y, int width, int height) { super.setThumbBounds(x, y, width, height); scrollbar.repaint(); } }); return scrollPane; } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { createAndShowGUI(); } }); } public static void createAndShowGUI() { JFrame f = new JFrame(); f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); f.getContentPane().add(new TranslucentScrollBarTest().makeUI()); f.setSize(320, 240); f.setLocationRelativeTo(null); f.setVisible(true); } }
这是我为私人项目所做的改进版本。 它还支持水平滚动条。
码：
import javax.swing.*; import javax.swing.plaf.basic.BasicScrollBarUI; import java.awt.*; /** * This is an implementation of a JScrollPane with a modern UI * * @author Philipp Danner * */ public class ModernScrollPane extends JScrollPane { private static final long serialVersionUID = 8607734981506765935L; private static final int SCROLL_BAR_ALPHA_ROLLOVER = 100; private static final int SCROLL_BAR_ALPHA = 50; private static final int THUMB_SIZE = 8; private static final int SB_SIZE = 10; private static final Color THUMB_COLOR = Color.Black; public ModernScrollPane(Component view) { this(view, VERTICAL_SCROLLBAR_AS_NEEDED, HORIZONTAL_SCROLLBAR_AS_NEEDED); } public ModernScrollPane(int vsbPolicy, int hsbPolicy) { this(null, vsbPolicy, hsbPolicy); } public ModernScrollPane(Component view, int vsbPolicy, int hsbPolicy) { setBorder(null); // Set ScrollBar UI JScrollBar verticalScrollBar = getVerticalScrollBar(); verticalScrollBar.setOpaque(false); verticalScrollBar.setUI(new ModernScrollBarUI(this)); JScrollBar horizontalScrollBar = getHorizontalScrollBar(); horizontalScrollBar.setOpaque(false); horizontalScrollBar.setUI(new ModernScrollBarUI(this)); setLayout(new ScrollPaneLayout() { private static final long serialVersionUID = 5740408979909014146L; @Override public void layoutContainer(Container parent) { Rectangle availR = ((JScrollPane) parent).getBounds(); availR.x = availR.y = 0; // viewport Insets insets = parent.getInsets(); availR.x = insets.left; availR.y = insets.top; availR.width -= insets.left + insets.right; availR.height -= insets.top + insets.bottom; if (viewport != null) { viewport.setBounds(availR); } boolean vsbNeeded = isVerticalScrollBarfNecessary(); boolean hsbNeeded = isHorizontalScrollBarNecessary(); // vertical scroll bar Rectangle vsbR = new Rectangle(); vsbR.width = SB_SIZE; vsbR.height = availR.height - (hsbNeeded ? vsbR.width : 0); vsbR.x = availR.x + availR.width - vsbR.width; vsbR.y = availR.y; if (vsb != null) { vsb.setBounds(vsbR); } // horizontal scroll bar Rectangle hsbR = new Rectangle(); hsbR.height = SB_SIZE; hsbR.width = availR.width - (vsbNeeded ? hsbR.height : 0); hsbR.x = availR.x; hsbR.y = availR.y + availR.height - hsbR.height; if (hsb != null) { hsb.setBounds(hsbR); } } }); // Layering setComponentZOrder(getVerticalScrollBar(), 0); setComponentZOrder(getHorizontalScrollBar(), 1); setComponentZOrder(getViewport(), 2); viewport.setView(view); } private boolean isVerticalScrollBarfNecessary() { Rectangle viewRect = viewport.getViewRect(); Dimension viewSize = viewport.getViewSize(); return viewSize.getHeight() > viewRect.getHeight(); } private boolean isHorizontalScrollBarNecessary() { Rectangle viewRect = viewport.getViewRect(); Dimension viewSize = viewport.getViewSize(); return viewSize.getWidth() > viewRect.getWidth(); } /** * Class extending the BasicScrollBarUI and overrides all necessary methods */ private static class ModernScrollBarUI extends BasicScrollBarUI { private JScrollPane sp; public ModernScrollBarUI(ModernScrollPane sp) { this.sp = sp; } @Override protected JButton createDecreaseButton(int orientation) { return new InvisibleScrollBarButton(); } @Override protected JButton createIncreaseButton(int orientation) { return new InvisibleScrollBarButton(); } @Override protected void paintTrack(Graphics g, JComponent c, Rectangle trackBounds) { } @Override protected void paintThumb(Graphics g, JComponent c, Rectangle thumbBounds) { int alpha = isThumbRollover() ? SCROLL_BAR_ALPHA_ROLLOVER : SCROLL_BAR_ALPHA; int orientation = scrollbar.getOrientation(); int x = thumbBounds.x; int y = thumbBounds.y; int width = orientation == JScrollBar.VERTICAL ? THUMB_SIZE : thumbBounds.width; width = Math.max(width, THUMB_SIZE); int height = orientation == JScrollBar.VERTICAL ? thumbBounds.height : THUMB_SIZE; height = Math.max(height, THUMB_SIZE); Graphics2D graphics2D = (Graphics2D) g.create(); graphics2D.setColor(new Color(THUMB_COLOR.getRed(), THUMB_COLOR.getGreen(), THUMB_COLOR.getBlue(), alpha)); graphics2D.fillRect(x, y, width, height); graphics2D.dispose(); } @Override protected void setThumbBounds(int x, int y, int width, int height) { super.setThumbBounds(x, y, width, height); sp.repaint(); } /** * Invisible Buttons, to hide scroll bar buttons */ private static class InvisibleScrollBarButton extends JButton { private static final long serialVersionUID = 1552427919226628689L; private InvisibleScrollBarButton() { setOpaque(false); setFocusable(false); setFocusPainted(false); setBorderPainted(false); setBorder(BorderFactory.createEmptyBorder()); } } } public static void main(String[] args) { JFrame frame = new JFrame(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setPreferredSize(new Dimension(400, 400)); JPanel content = new JPanel(); content.setBackground(Color.WHITE); content.setPreferredSize(new Dimension(500, 500)); content.add(new JLabel("test")); frame.add(new ModernScrollPane(content)); frame.pack(); frame.setVisible(true); } }
遗憾的是，提议的解决方案将破坏JTable并且不会显示表头，但我发现这个解决方案似乎有效。