eeerggrrhh，你必须看看ItemListener，并通过使用这个演示......
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
/** @see http://stackoverflow.com/questions/5806712 */
public class ComponentEventDemo extends JPanel
implements ActionListener, ComponentListener, ItemListener {
private static final long serialVersionUID = 1L;
private JFrame frame;
private JTextArea display;
private JLabel label;
private String newline = "\n";
private JTextField field1TF;
private JTextField field2TF;
private JCheckBox checkbox;
public ComponentEventDemo() {
super(new BorderLayout());
display = new JTextArea();
display.setEditable(false);
JPanel panel = new JPanel(new GridLayout(0, 4));
field1TF = new JTextField();
field1TF.setDisabledTextColor(Color.red);
field2TF = new JTextField();
field2TF.setDisabledTextColor(Color.red);
label = new JLabel("This is a label", JLabel.CENTER);
label.addComponentListener(this);
checkbox = new JCheckBox("Label visible", true);
checkbox.addActionListener(this);
checkbox.addComponentListener(this);
checkbox.addItemListener(this);
panel.add(checkbox);
panel.add(label);
panel.add(field1TF);
panel.add(field2TF);
panel.addComponentListener(this);
JScrollPane scrollPane = new JScrollPane(display);
scrollPane.setPreferredSize(new Dimension(650, 200));
frame = new JFrame("ComponentEventDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(scrollPane, BorderLayout.CENTER);
frame.add(panel, BorderLayout.SOUTH);
frame.addComponentListener(this);
frame.setLocation(200, 200);
frame.pack();
frame.setVisible(true);
}
public void itemStateChanged(ItemEvent evt) {
System.out.println("STATE CHANGED!");//TODO debug code
if (evt.getStateChange() == ItemEvent.SELECTED) {
int returnVal = JOptionPane.showConfirmDialog(frame, "blablatext");
if (returnVal == 0) {
field1TF.setText("SELECTED - OK btn");
field1TF.setEditable(false);
field2TF.setText("SELECTED - OK btn");
field2TF.setEditable(false);
} else if (returnVal == 1) {
field1TF.setText("SELECTED - canc btn");
field1TF.setEditable(true);
field2TF.setText("SELECTED - canc btn");
field2TF.setEditable(true);
}
} else if (evt.getStateChange() == ItemEvent.DESELECTED) {
field1TF.setEditable(true);
field1TF.setText("DESELECTED");
field2TF.setEditable(true);
field2TF.setText("DESELECTED");
}
}
@Override
public void actionPerformed(ActionEvent e) {
boolean selected = checkbox.isSelected();
System.out.println("Checkbox "
+ (selected ? "is" : "is not") + " selected.");
if (selected) {
//some stuff
} else {
//some reversal stuff
}
}
protected void displayMessage(String message) {
display.append(message + newline);
display.setCaretPosition(display.getDocument().getLength());
}
@Override
public void componentHidden(ComponentEvent e) {
displayMessage(e.getComponent().getClass().getName() + " --- Hidden");
}
@Override
public void componentMoved(ComponentEvent e) {
displayMessage(e.getComponent().getClass().getName() + " --- Moved");
}
@Override
public void componentResized(ComponentEvent e) {
displayMessage(e.getComponent().getClass().getName() + " --- Resized ");
}
@Override
public void componentShown(ComponentEvent e) {
displayMessage(e.getComponent().getClass().getName() + " --- Shown");
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
ComponentEventDemo ced = new ComponentEventDemo();
}
});
}
}