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| 14. 4. 4. 添加PropertyChangeListener到AbstractButton |
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import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.AbstractButton;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
class AbstractButtonPropertyChangeListener implements PropertyChangeListener {
public void propertyChange(PropertyChangeEvent e) {
String propertyName = e.getPropertyName();
System.out.println("Property Name: "+propertyName);
if (e.getPropertyName().equals(AbstractButton.TEXT_CHANGED_PROPERTY)) {
String newText = (String) e.getNewValue();
String oldText = (String) e.getOldValue();
System.out.println(oldText + " changed to " + newText);
} else if (e.getPropertyName().equals(AbstractButton.ICON_CHANGED_PROPERTY)) {
Icon icon = (Icon) e.getNewValue();
if (icon instanceof ImageIcon) {
System.out.println("New icon is an image");
}
}
}
}
public class AbstractButtonPropertyChangeListenerDemo {
public static void main(String[] a) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
AbstractButton bn = new JButton("asdf");
bn.addPropertyChangeListener(new AbstractButtonPropertyChangeListener());
bn.setText("fdsa");
frame.add(bn);
frame.setSize(300, 200);
frame.setVisible(true);
}
}
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