 |
|
|
 首页 |
名片设计 CorelDRAW Illustrator AuotoCAD Painter 其他软件 Photoshop Fireworks Flash |
|
在Windows的“开始”菜单上，会在菜单左侧显示一幅图像。很多基于Windows的软件也有类似效果的菜单。用Java Swing可以制作出类似效果的菜单吗？答案当然是肯定的，而且异常简朴。 我们首先从Swing的JPopupMenu组件进行扩展，让其接受一个图片，显示在左侧；或者接受一个字符串，动态生成图片后，在显示在左侧。为了避免预备图片的麻烦，我们就以动态生成内存图片为例，编写一个JImagedPopupMenu类。 JImagedPopupMenu在创建时可以接受一个字符串，生成一副内存图片BufferedImage。然后，我们需要覆盖JComponent的getInsets方式，重新计算Inset的left值，将其在原数值基础上加上图片的宽度，然后返回： ?public Insets getInsets() { ??????? Insets insets = (Insets)super.getInsets().clone(); ??????? insets.left += imageIcon.getIconWidth(); ??????? return insets; ??? } 最后，覆盖paintComponent方式，在原基础上增加图片的绘制： ??? public void paintComponent(Graphics g) { ??????? super.paintComponent(g); ??????? if (imageIcon != null) { ??????????? Insets insets = getInsets(); ??????????? g.drawImage(imageIcon.getImage(), ??????????????????????? insets.left - imageIcon.getIconWidth(), ??????????????????????? insets.top, ??????????????????????? null); ??????? } ??? } 完整代码如下： import java.awt.*; import java.awt.event.*; import java.awt.geom.*; import java.awt.image.*; import javax.swing.*; public class ImageMenu extends JPopupMenu { ??? private Font font = new Font("Dialog", Font.BOLD, 13); ??? private ImageIcon imageIcon = null; ??? public ImageMenu(ImageIcon imageIcon) { ??????? this.imageIcon = imageIcon; ??? } ??? public ImageMenu(String text) { ??????? this.imageIcon = createImage(text); ??? } ??? private ImageIcon createImage(String text) { ??????? BufferedImage bi = new BufferedImage(30, 1000, BufferedImage.TYPE_INT_ARGB); ??????? ImageIcon image = new ImageIcon(bi); ??????? Graphics2D g2d = bi.createGraphics(); ??????? GradientPaint paint = new GradientPaint(0, 0, Color.yellow, 30, 10, Color.red, true); ??????? g2d.setPaint(paint); ??????? g2d.fillRect(0, 0, bi.getWidth(), bi.getHeight()); ??????? AffineTransform at = new AffineTransform(); ??????? at.rotate( -Math.PI / 2); ??????? g2d.setTransform(at); ??????? g2d.setColor(Color.white); ??????? g2d.setFont(font); ??????? g2d.drawString(text, -180, bi.getWidth() / 2); ??????? return image; ??? } ??? public Insets getInsets() { ??????? Insets insets = (Insets)super.getInsets().clone(); ??????? insets.left += imageIcon.getIconWidth(); ??????? return insets; ??? } ??? public void paint(Graphics g) { ??????? super.paint(g); ??????? if (imageIcon != null) { ??????????? Insets insets = getInsets(); ??????????? g.drawImage(imageIcon.getImage(), ??????????????????????? insets.left - imageIcon.getIconWidth(), ??????????????????????? insets.top, ??????????????????????? null); ??????? } ??? } ??? public static void main(String[] args) { ??????? final JFrame frame = new JFrame(); ??????? frame.setSize(600, 500); ??????? frame.setTitle("ImageMenu"); ??????? final ImageMenu menu = new ImageMenu("Windows XP Perfessional"); ??????? menu.add(new JMenuItem("Winzip 8.0")); ??????? menu.addSeparator(); ??????? menu.add(new JMenuItem("Programs")); ??????? menu.add(new JMenuItem("Document")); ??????? menu.add(new JMenuItem("Settings")); ??????? menu.add(new JMenuItem("Search")); ??????? menu.add(new JMenuItem("Help and Support")); ??????? menu.add(new JMenuItem("Run...")); ??????? menu.addSeparator(); ??????? menu.add(new JMenuItem("Shut Down...")); ??????? JLabel label = new JLabel("Right click me to show image popup menu."); ??????? label.addMouseListener(new java.awt.event.MouseAdapter() { ??????????? public void mouseReleased(MouseEvent e) { ??????????????? if (e.isPopupTrigger()) { ??????????????????? menu.show(frame, e.getPoint().x, e.getPoint().y); ??????????????? } ??????????? } ??????? }); ??????? frame.getContentPane().add(label, BorderLayout.CENTER); ??????? frame.show(); ??? } } 同样，采用这种方式，也可以将JMenu扩展出同样的效果。 返回类别: 教程 上一教程: EJB之无状态会话Bean简朴应用－学习与实践 下一教程: 为什么Java中继续是有害的 您可以阅读与"用Java创建带图像的菜单"相关的教程: · 用Java创建带图标和缩进的JComboBox · 用鼠标控制滚动的菜单条！(JAVASCRIPT) · java图像浏览器 · 创建 Java .exe 文件 · Effective Java -->（一）创建和销毁对象 |
  |
| 快精灵印艺坊 版权所有 |
首页 会员中心在线印刷在线编辑付款方式索取样品设计指南连锁门店
|
||
