shoot, something like this, when the component (here JLabel, not JPanel) has a preferred set of values, then put it in another JPanel that uses the appropriate layout, here GridBagLayout, which with default settings will center the component and add GridBagLayout, using JPanel for CardLayout using the panel ::
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.Border;
public class MultiSizedPanels {
private static void createAndShowUI() {
final CardLayout cardLayout = new CardLayout();
final JPanel cardHolder = new JPanel(cardLayout);
JLabel[] labels = {
new JLabel("Small Label", SwingConstants.CENTER),
new JLabel("Medium Label", SwingConstants.CENTER),
new JLabel("Large Label", SwingConstants.CENTER)};
for (int i = 0; i < labels.length; i++) {
int padding = 50;
Dimension size = labels[i].getPreferredSize();
size = new Dimension(size.width + 2 * (i + 1) * padding, size.height + 2 * (i + 1) * padding);
labels[i].setPreferredSize(size);
Border lineBorder = BorderFactory.createLineBorder(Color.blue);
labels[i].setBorder(lineBorder);
JPanel containerPanel = new JPanel(new GridBagLayout());
containerPanel.add(labels[i]);
cardHolder.add(containerPanel, String.valueOf(i));
}
JButton nextButton = new JButton("Next");
nextButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
cardLayout.next(cardHolder);
}
});
JPanel btnHolder = new JPanel();
btnHolder.add(nextButton);
JFrame frame = new JFrame("MultiSizedPanels");
frame.getContentPane().add(cardHolder, BorderLayout.CENTER);
frame.getContentPane().add(btnHolder, BorderLayout.SOUTH);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
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