JButton大改造之二 - 五芒星之辉

原文地址：http://www.blogjava.net/ruislan/archive/2007/09/12/144464.html 版权归原作者所有；

 

 

 

/** * @(#)RJButton.java 0.1.0 2007-9-11 */ package ruislan.rswing; import java.awt.AlphaComposite; import java.awt.Color; import java.awt.Dimension; import java.awt.Font; import java.awt.GradientPaint; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Point; import java.awt.RenderingHints; import java.awt.Shape; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.geom.Arc2D; import java.awt.geom.GeneralPath; import java.awt.geom.RoundRectangle2D; import javax.swing.JButton; /** * Custom JButton * * @version 0.1.0 * @author ruislan <a href="mailto:[email protected]" mce_href="mailto:[email protected]"></a> */ public class RButton extends JButton { private static final long serialVersionUID = 39082560987930759L; public static final Color BUTTON_COLOR1 = new Color(205, 255, 205); public static final Color BUTTON_COLOR2 = new Color(51, 154, 47); // public static final Color BUTTON_COLOR1 = new Color(125, 161, 237); // public static final Color BUTTON_COLOR2 = new Color(91, 118, 173); public static final Color BUTTON_FOREGROUND_COLOR = Color.WHITE; private boolean hover; private int style; public static final int ROUND_RECT = 0; public static final int LEFT_ROUND_RECT = 1; public static final int RIGHT_ROUND_RECT = 2; public static final int BALL = 3; public static final int STAR = 4; public RButton() { this(ROUND_RECT); } public RButton(int style) { this.style = style; if (BALL == style) { setPreferredSize(new Dimension(42, 42)); } else if (STAR == style) { setPreferredSize(new Dimension(42, 42)); } setFont(new Font("system", Font.PLAIN, 12)); setBorderPainted(false); setForeground(BUTTON_COLOR2); setFocusPainted(false); setContentAreaFilled(false); addMouseListener(new MouseAdapter() { @Override public void mouseEntered(MouseEvent e) { setForeground(BUTTON_FOREGROUND_COLOR); hover = true; repaint(); } @Override public void mouseExited(MouseEvent e) { setForeground(BUTTON_COLOR2); hover = false; repaint(); } }); } @Override protected void paintComponent(Graphics g) { Graphics2D g2d = (Graphics2D) g.create(); int h = getHeight(); int w = getWidth(); float tran = 1F; if (!hover) { tran = 0.3F; } g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); GradientPaint p1; GradientPaint p2; if (getModel().isPressed()) { p1 = new GradientPaint(0, 0, new Color(0, 0, 0), 0, h - 1, new Color(100, 100, 100)); p2 = new GradientPaint(0, 1, new Color(0, 0, 0, 50), 0, h - 3, new Color(255, 255, 255, 100)); } else { p1 = new GradientPaint(0, 0, new Color(100, 100, 100), 0, h - 1, new Color(0, 0, 0)); p2 = new GradientPaint(0, 1, new Color(255, 255, 255, 100), 0, h - 3, new Color(0, 0, 0, 50)); } g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, tran)); GradientPaint gp = new GradientPaint(0.0F, 0.0F, BUTTON_COLOR1, 0.0F, h, BUTTON_COLOR2, true); g2d.setPaint(gp); switch (style) { case ROUND_RECT: { RoundRectangle2D.Float r2d = new RoundRectangle2D.Float(0, 0, w - 1, h - 1, 20, 20); Shape clip = g2d.getClip(); g2d.clip(r2d); g2d.fillRect(0, 0, w, h); g2d.setClip(clip); g2d.setPaint(p1); g2d.drawRoundRect(0, 0, w - 1, h - 1, 20, 20); g2d.setPaint(p2); g2d.drawRoundRect(1, 1, w - 3, h - 3, 18, 18); break; } case LEFT_ROUND_RECT: { RoundRectangle2D.Float r2d = new RoundRectangle2D.Float(0, 0, (w - 1) + 20, h - 1, 20, 20); Shape clip = g2d.getClip(); g2d.clip(r2d); g2d.fillRect(0, 0, w, h); g2d.setClip(clip); g2d.setPaint(p1); g2d.drawRoundRect(0, 0, (w - 1) + 20, h - 1, 20, 20); g2d.setPaint(p2); g2d.drawRoundRect(1, 1, (w - 3) + 20, h - 3, 18, 18); g2d.setPaint(p1); g2d.drawLine(w - 1, 1, w - 1, h); g2d.setPaint(p2); g2d.drawLine(w - 2, 2, w - 2, h - 1); break; } case RIGHT_ROUND_RECT: { RoundRectangle2D.Float r2d = new RoundRectangle2D.Float(-20, 0, (w - 1) + 20, h - 1, 20, 20); Shape clip = g2d.getClip(); g2d.clip(r2d); g2d.fillRect(0, 0, w, h); g2d.setClip(clip); g2d.setPaint(p1); g2d.drawRoundRect(-20, 0, (w - 1) + 20, h - 1, 20, 20); g2d.setPaint(p2); g2d.drawRoundRect(-19, 1, (w - 3) + 20, h - 3, 18, 18); g2d.setPaint(p1); g2d.drawLine(0, 1, 0, h); g2d.setPaint(p2); g2d.drawLine(1, 2, 1, h - 1); break; } case BALL: { Arc2D.Float a2d = new Arc2D.Float(0, 0, w, h, 0, 360, Arc2D.CHORD); Shape clip = g2d.getClip(); g2d.clip(a2d); g2d.fillRect(0, 0, w, h); g2d.setClip(clip); g2d.setPaint(p1); g2d.drawOval(0, 0, w - 1, h - 1); g2d.setPaint(p2); g2d.drawOval(1, 1, w - 3, h - 3); break; } case STAR: { int x = w / 2; int y = h / 2; int r = w / 2; // 计算五个顶点 Point[] ps = new Point[5]; for (int i = 0; i <= 4; i++) { ps[i] = new Point((int) (x - r * Math.sin((i * 72 + 36) * 2 * Math.PI / 360)), (int) (y + r * Math.cos((i * 72 + 36) * 2 * Math.PI / 360))); } GeneralPath star = new GeneralPath(); star.moveTo(ps[3].x, ps[3].y); star.lineTo(ps[0].x, ps[0].y); star.lineTo(ps[2].x, ps[2].y); star.lineTo(ps[4].x, ps[4].y); star.lineTo(ps[1].x, ps[1].y); star.lineTo(ps[3].x, ps[3].y); star.closePath(); Shape clip = g2d.getClip(); g2d.clip(star); g2d.fillRect(0, 0, w, h); g2d.setClip(clip); g2d.setPaint(p1); g2d.draw(star); g2d.setPaint(p2); g2d.draw(star); break; } default: break; } g2d.dispose(); super.paintComponent(g); } }

 

这个代码的其他地方我就不多说了，今天主要是讲一下如何来clip内容，从而弄出我们想要的按钮形状（当然其他组件也可以）
如图所示，假设我们的按钮是黑色的框，我们想要的是红色的框，那么我们首先绘出我们想要的Shape，然后得到这个按钮的Shape，然后进行合并剪裁，也就是说将两个Shape合起来，然后交集部分留下，其余的去除，这样就得到了我们所想要的图形（五角星那个图我们对五角星进行了封闭closePath）。