Question

I am trying to work out how to navigate across multiple panels in swing. I would like to do this by using the CardLayout as opposed to using glass panels as from what I have read it seems that this is the correct tool for this job (however, feel free to correct me if you know otherwise). I have written a test case which almost achieves this but falls short on 2 fronts. It uses the depreciated “show()” method and furthermore after it switches to the second card the buttons from card1 begin to mysteriously float through to the surface again!

public class test extends JPanel implements ActionListener{
    final static int extraWindowWidth = 100;
    JButton jbtnOne = new JButton("Button 1");
        JPanel cardPanel = new JPanel(new CardLayout());
        JPanel card1 = new JPanel();
        JPanel card2 = new JPanel();

    public void addComponentToPane(Container pane) {

        //Create the "cards".
        JPanel card1 = new JPanel() {
            public Dimension getPreferredSize() {
                Dimension size = super.getPreferredSize();
                size.width += extraWindowWidth;
                return size;
            }
        };


        card1.add(jbtnOne);
        card1.add(new JButton("Button 2"));
        card1.add(new JButton("Button 3"));     
        card2.add(new JTextField("TextField", 20));

        cardPanel.add(card1, "card1");
        cardPanel.add(card2, "card2");

        pane.add(cardPanel, BorderLayout.CENTER);
        jbtnOne.addActionListener(this);
    }

    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("TabDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        test demo = new test();
        demo.addComponentToPane(frame.getContentPane());

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {

        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }

    public void actionPerformed(ActionEvent e) {
        // TODO Auto-generated method stub
        if(e.getSource() ==  jbtnOne){
            System.out.println("HERE");
            card2.show();
        }
    }
}

Answer 1

The CardLayout is managing the components so you will need to call show on the CardLayout instead of JPanel#show:

CardLayout cardLayout = (CardLayout) cardPanel.getLayout();
cardLayout.show(cardPanel, "card2");

Alternatively, when switching card components, you could also use

cardLayout.next(cardPanel);