JradioButton itemStateChanged listener 例子，,package cn.o

JradioButton itemStateChanged listener 例子，,package cn.o

package cn.outofmemory;import java.awt.BorderLayout;import java.awt.Component;import java.awt.Container;import java.awt.event.ItemEvent;import java.awt.event.ItemListener;import javax.swing.ButtonGroup;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JRadioButton;import javax.swing.WindowConstants;public class JradioButtonExample extends JFrame {    private JRadioButton s, m, l;    private JButton jbutton;    public JradioButtonExample(String str) {        super(str);        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);        Container cPane = this.getContentPane();        ButtonGroup buttonGroup = new ButtonGroup();        s = new JRadioButton("Small");        m = new JRadioButton("Medium");        l = new JRadioButton("Large");        buttonGroup.add(s);        buttonGroup.add(m);        buttonGroup.add(l);        jbutton = new JButton("Click me!");        jbutton.setBounds(100, 100, 100, 100);        JPanel jPaneCent = new JPanel();        jPaneCent.setLayout(null);        jPaneCent.add(jbutton);        cPane.add(jPaneCent, BorderLayout.CENTER);        JPanel jPanelNor = new JPanel();        jPanelNor.add(s);        jPanelNor.add(m);        jPanelNor.add(l);        cPane.add(jPanelNor, BorderLayout.NORTH);        ChangeSize chsize = new ChangeSize(jbutton);        s.addItemListener(chsize);        m.addItemListener(chsize);        l.addItemListener(chsize);    }    public static void main(String[] args) {        JFrame jFrame = new JradioButtonExample("JRadioButton example");        jFrame.setSize(300, 200);        jFrame.setVisible(true);    }}class ChangeSize implements ItemListener {    private Component component;    public ChangeSize(Component comp) {        component = comp;    }    @Override    public void itemStateChanged(ItemEvent event) {        String s = (String) event.getItem();        if (s.equals("Small")) {            component.setSize(60, 10);        } else if (s.equals("Medium")) {            component.setSize(90, 70);        } else if (s.equals("Large")) {            component.setSize(260,105);        }    }}