JavaSwing与JavaFX开发指南

### Java Swing与JavaFX开发指南 #### 1. Swing API 动画创建 在Java中，通过Swing API可以实现一些有趣的界面效果，比如创建动画按钮。下面是一个创建动画按钮的示例代码： ```java public void mouseEntered(MouseEvent e) { currentColor = startColor; startTime = System.nanoTime() / 1000000; timer.start(); } @Override public void mouseExited(MouseEvent e) { currentColor = startColor; animButton.setForeground(currentColor); repaint(); timer.stop(); } ``` 当鼠标进入按钮区域时，动画开始；鼠标离开时，动画停止。这里使用了`Swing`的`Timer` API来模拟动画时间线。以下是创建`Swing Timer`的代码： ```java Timer timer = new Timer(30, new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // every 30 milliseconds run code here... } }); ``` 整个动画的持续时间为250毫秒，当时间耗尽或鼠标离开按钮时，调用`timer.stop()`方法停止动画。在`actionPerformed()`方法中，调用`repaint()`方法刷新GUI。 #### 2. 使用JLayer组件进行表单验证 在开发表单应用时，验证用户输入是非常重要的。可以使用Java 7的`JLayer`组件来实现表单字段的验证，并通过图标提示用户。以下是一个验证电子邮件字段的示例代码： ```java package org.java7recipes.chapter14.recipe14_24; import java.awt.*; import java.io.IOException; import javax.imageio.*; import javax.swing.*; import javax.swing.plaf.LayerUI; public class UsingJXLayer extends JPanel { public UsingJXLayer() { setLayout(new BorderLayout(10, 20)); JPanel inputArea = new JPanel(); JLabel emailLbl = new JLabel("Email"); final JTextField emailFld = new JTextField(20); Image error = null; Image warning= null; try { error = ImageIO.read(this.getClass().getResource("error.png")); warning = ImageIO.read(this.getClass().getResource("warning.png")); } catch (IOException ex) { ex.printStackTrace(); } LayerUI<JTextField> layerUI = new EmailValidationLayerUI(error, warning); JLayer<JTextField> layeredEmail = new JLayer<>(emailFld, layerUI); inputArea.add(emailLbl); inputArea.add(layeredEmail); add(inputArea, BorderLayout.NORTH); JComponent buttonArea = new JPanel(new FlowLayout(FlowLayout.RIGHT)); final JButton saveButt = new JButton("Save"); buttonArea.add(saveButt); add(buttonArea, BorderLayout.SOUTH); } public static void main(String[] args) { final JPanel c = new UsingJXLayer(); c.setPreferredSize(new Dimension(402, 118)); // Queueing GUI work to be run using the EDT. SimpleAppLauncher.launch("Chapter 14-24 Using JLayer.", c); } } class EmailValidationLayerUI extends LayerUI<JTextField> { Image errorImg; Image warningImg; public EmailValidationLayerUI(Image error, Image warning) { this.errorImg = error; this.warningImg = warning; } @Override public void paint(Graphics g, JComponent comp) { super.paint(g, comp); JLayer jlayer = (JLayer) comp; JTextField emailFld = (JTextField) jlayer.getView(); String text = emailFld.getText(); String regEx = ".+@.+\\.[A-Za-z]+"; int x = comp.getWidth() - 12; int y = (comp.getHeight() - 8) / 2; if (text.length() > 0 & ```