第9节+反转按钮.doc

第9章 反转按钮、复选框和单选框 　　本章介绍三种Swing按钮：反转按钮、复选按钮和单选按钮，它们分别由JToggleButton、JCheckBox和JRadioButton类代表。　　这三种按钮都是AbstractButton类的最终扩展。AbstractButton类实现了这三个类提供的几乎所有功能。有关AbstractButton类的更多信息，请参见第8章“标签与按钮”。 9.1 JToggleButton类 ? 例9-1 JToggleButton的一个简单例子 import java.awt.*;import java.awt.event.*;import javax.swing.*; public class Test extends JApplet {public Test() {Container contentPane = getContentPane();ImageIcon icon = new ImageIcon(togglebuttonImage.gif); JToggleButton button = new JToggleButton(icon);contentPane.setLayout(new FlowLayout());contentPane.add(button);}} 9.1.1 JToggleButton属性 ? 9.1.2 JToggleButton事件 ? 例9-2 用一个子项监听器来处理反转按钮的选取操作 import java.awt.*;import java.awt.event.*;import javax.swing.*;import javax.swing.event.*; public class Test extends JApplet {public Test() {Container contentPane = getContentPane();ImageIcon icon = new ImageIcon(togglebuttonImage.gif);final JToggleButton button = new JToggleButton(icon); contentPane.setLayout(new FlowLayout());contentPane.add(button); button.addItemListener(new ItemListener() {public void itemStateChanged(ItemEvent e) {int state = e.getStateChange();String s; if(state == ItemEvent.SELECTED) s = selected;else s = deselected; showStatus(Item Event: + s);}});}} 9.1.3 JToggleButton类总结 ? 例9-3 创建反转按钮 import java.awt.*;import java.awt.event.*;import javax.swing.*; public class Test extends JApplet {public Test() {Container contentPane = getContentPane();Icon icon = new ImageIcon(beach_umbrella.gif);JToggleButton button_1 = new JToggleButton(),button_2 = new JToggleButton(icon),button_3 = new JToggleButton(icon, true),button_4 = new JToggleButton(beach),button_5 = new JToggleButton(beach,true),button_6 = new JToggleButton(beach,icon),button_7 = new JToggleButton(beach,icon,true);contentPane.setLayout(new FlowLayout());contentPane.add(button_1);contentPane.add(button_2);contentPane.add(button_3);contentPane.add(button_4);contentPane.add(button_5);contentPane.add(button_6);content