Trying to use cards layout, but cant make show work

Question

im trying to to use cards layout, and i have 2 buttons at the the top that supoose to change the card but for some reason it wont work, the next method works but the show or first\last doesnt, ofcourse i cant use next, cause i want a specific card for every button, here is my code:

     cards = new CardLayout();
    cardPanel = new JPanel();
    cardPanel.setLayout(cards);
    cards.show(cardPanel, "gapas");

    JPanel firstCard = new JPanel();
    firstCard.setBackground(Color.WHITE);;


    JPanel secondCard = new JPanel();
    secondCard.setBackground(Color.blue);


    cardPanel.add(firstCard, "kalam");
    cardPanel.add(secondCard, "gapan");

    guiFrame.add(tabsPanel,BorderLayout.NORTH);
    guiFrame.add(cardPanel,BorderLayout.CENTER);
    guiFrame.setVisible(true);
}

ActionListener action = new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent e) {
        if(e.getActionCommand().matches("kalam")){
            cards.show(cardPanel,"kalam");
            System.out.println("kalam");
        }
        else{
            cards.show(cardPanel, "gapas");
            System.out.println("gapas");
        }

    }
};

Answer 1

I think you want something like this.

public class TestCard extends JFrame implements ActionListener {

CardLayout cards;
JPanel cardPanel, tabsPanel;
JButton b1, b2;

public TestCard() {
    b1= new JButton("kalam");
    b2= new JButton("gapas");
    tabsPanel = new JPanel();
    cards = new CardLayout();
    cardPanel = new JPanel();
    cardPanel.setLayout(cards);

    JPanel firstCard = new JPanel();
    firstCard.setBackground(Color.WHITE);


    JPanel secondCard = new JPanel();
    secondCard.setBackground(Color.blue);


    cardPanel.add(firstCard, "kalam");
    cardPanel.add(secondCard, "gapas");
    tabsPanel.add(b1);
    tabsPanel.add(b2);

    add(tabsPanel, BorderLayout.NORTH);
    add(cardPanel, BorderLayout.CENTER);
    b1.addActionListener(this);
    b2.addActionListener(this);
    setSize(800, 600);

    cards.show(cardPanel, "gapas");
    setVisible(true);
}

@Override
public void actionPerformed(ActionEvent e) {
    if (e.getActionCommand().matches("kalam")) {
        cards.show(cardPanel, "kalam");
        System.out.println("kalam");
    } else {
        cards.show(cardPanel, "gapas");
        System.out.println("gapas");
    }
}
public static void main(String[] args) {
    new TestCard();
}
}

Answer 2

Documentation states: show (Container parent, String name) Flips to the component that was added to this layout with the specified name, using the addLayoutComponent method.

You add two items:

• kalam
• gapan

but you try to show: gapas.

Additionally I would add first and then try 2 show.