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The Java method isRollover () does not generate an event in my swing application

I am reading a wonderful book called Swing: A Beginner's Guide. The book has such code that creates a button and a label warning of events that change the state of a button:

//Demonstrate a change listener and the button model

package swingexample2_6;

import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;

public class ChangeDemo {

    JButton jbtn;
    JLabel jlab;

    public ChangeDemo() {
        //Create a new JFrame container
        JFrame jfrm = new JFrame("Button Change Events");

        //Specify FlowLayout for the layout manager
        jfrm.getContentPane().setLayout(new FlowLayout());

        //Give the frame an initial size
        jfrm.setSize(250, 160);

        //Terminate the program when the user closes the application
        jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create an empty label
        jlab = new JLabel();

        //Make a button
        jbtn = new JButton("Press for Change Event Test");

        //--Add change listener
        jbtn.addChangeListener(new ChangeListener() {

            @Override
            public void stateChanged(ChangeEvent ce) {
                ButtonModel mod = jbtn.getModel();
                String what = "";

                if (mod.isEnabled()) {
                    what += "Enabled<br>";
                }
                if (mod.isRollover()) {
                    what += "Rollover<br>";
                }
                if (mod.isArmed()) {
                    what += "Armed<br>";
                }
                if (mod.isPressed()) {
                    what += "Pressed<br>";
                }

                //Notice that this label text is HTML
                jlab.setText("<html>Current stats:<br>" + what);
            }
        });


        //Add the components to the content pane
        jfrm.getContentPane().add(jbtn);
        jfrm.getContentPane().add(jlab);

        //Display the frame
        jfrm.setVisible(true);
    }

    public static void main(String[] args) {
        //Create the frame on the event dispatching thread
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new ChangeDemo();
            }
        });
    }
}

Everything works fine except for the rollover event. The main operating system is Mac OS Lion. Should I blame Leo for this swing problem or am I doing something wrong? Thank.

Update 1: My picture of Neatbeans settings (hope this helps) settings

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2 answers

Leopard tested code with the Java version 1.6.0_26shown below. The triple tag </html>corrected the fallout of the backlight.

. , setRolloverEnabled(true) . , Mac UI, com.apple.laf.AquaButtonUI, , isRollover() true. , , true:

System.getProperty("os.name").startsWith("Mac OS X")

, setRolloverIcon().

import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;

public class ChangeDemo {

    private JButton jbtn;
    private JLabel jlab;

    public ChangeDemo() {
        JFrame jfrm = new JFrame("Button Change Events");
        jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        jfrm.setLayout(new GridLayout(0, 1));
        jlab = new JLabel("", JLabel.CENTER);
        jbtn = new JButton("Press for Change Event Test");
        jbtn.setRolloverEnabled(true);

        jbtn.addChangeListener(new ChangeListener() {

            @Override
            public void stateChanged(ChangeEvent ce) {
                ButtonModel mod = jbtn.getModel();
                String what = "";

                if (mod.isEnabled()) {
                    what += "Enabled<br>";
                }
                if (mod.isRollover()) {
                    what += "Rollover<br>";
                }
                if (mod.isArmed()) {
                    what += "Armed<br>";
                }
                if (mod.isPressed()) {
                    what += "Pressed<br>";
                }

                //Notice that this label text is HTML
                jlab.setText("<html>Current stats:<br>" + what + "</html>");
            }
        });

        JPanel panel = new JPanel();
        panel.setBorder(BorderFactory.createEmptyBorder(50, 10, 0, 10));
        panel.add(jbtn);
        jfrm.add(panel);
        jfrm.add(jlab);

        jfrm.pack();
        jfrm.setLocationRelativeTo(null);
        jfrm.setVisible(true);
    }

    public static void main(String[] args) {
        //Create the frame on the event dispatching thread
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                ChangeDemo changeDemo = new ChangeDemo();
            }
        });
    }
}
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. , , OP Mac, .

Windows 7, , ​​ "". "Basic", .

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