例如，
import java.awt.cardlayout;
import java.awt.Dimension;
import java.awt.event.*;
import javax.swing.*;
public class RepaintTest extends JPanel {
private static final int PREF_W = 400;
private static final int PREF_H = PREF_W;
private static final int LABEL_COUNT = 3;
private static final String LABEL_PANEL = "label panel";
private static final Object BLANK_COMPONENT = "blank component";
private static final int TIMER_DELAY = 2000;
private cardlayout cardlayout = new cardlayout();
public Repainttest() {
JPanel labelPanel = new JPanel();
for (int i = 0; i < LABEL_COUNT; i++) {
labelPanel.add(new JLabel("Label " + (i + 1)));
}
setLayout(cardlayout);
add(labelPanel, LABEL_PANEL);
add(new JLabel(), BLANK_COMPONENT);
new Timer(TIMER_DELAY, new TimerListener()).start();
}
@Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
private class TimerListener implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
cardlayout.next(RepaintTest.this);
}
}
private static void createAndShowGui() {
RepaintTest mainPanel = new Repainttest();
JFrame frame = new JFrame("RepaintTest");
frame.setDefaultCloSEOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokelater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
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