import java.awt.CardLayout;

import javax.swing.JButton;
import javax.swing.JFrame;

public class MainWindow extends JFrame {
    JButton button1 = new JButton("gomb1");
    JButton button2 = new JButton("gomb2");
    JButton button3 = new JButton("gomb3");
    CardLayout card = new CardLayout(50, 100);

    public MainWindow() {
        this.button1.addActionListener(e->onClickButton());
        this.button2.addActionListener(e->onClickButton());
        this.button3.addActionListener(e->onClickButton());
        this.setLayout(card);
        this.add(button1);
        this.add(button2);
        this.add(button3);


        this.setTitle("CardLayout");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.pack();
        this.setVisible(true);
    }
    private void onClickButton() {
        this.card.next(this.getContentPane());
    }
}