java在单击Jbutton后更改JPanel

Question

我的代码中有2个JPanel。第一个是Furutsu7，它是主要的JPanel，包括我的游戏。第二个JPanel是start Jbutton。我试图实现的是，在用户单击Jbutton之后，furutsu7jpanel将出现

这是我创建按钮的设置类

public void setup(){
    JFrame f = new JFrame("Start ");
    JPanel card1 = new JPanel();
    JPanel card2 = new JPanel();


    cards = new JPanel(new CardLayout());

    JButton Card1Button = new JButton("Start");
    card1.add(Card1Button);
    JButton Card2Button = new JButton("Exit");
    card2.add(Card2Button);

    cards.add(card1, "C1");
    cards.add(card2, "C2");

    f.add(cards, BorderLayout.CENTER);

    f.setTitle("Furutsu");
    f.setSize(500, 300);
    f.setLocationRelativeTo(null);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setVisible(true);



 }

我需要帮助的是，为了切换到Furutsu JPanel，我应该在执行的操作中加入什么内容

public void actionPerformed(ActionEvent e) {


}

Answer 1

将CardLayout设置为类的一个字段，以便在actionPerformed方法中更轻松地访问它。否则，您需要调用(CardLayout) cards.getLayout()，这是一件风险更大的事情。例如：

public class MyClass implements ActionListener {
    private CardLayout cardLayout = new CardLayout();
    private JPanel cards = new JPanel(cardLayout);

    public void setup(){
        JFrame f = new JFrame("Start ");
        JPanel card1 = new JPanel();
        JPanel card2 = new JPanel();

        // cards = new JPanel(new CardLayout());

        JButton Card1Button = new JButton("Start");
        card1.add(Card1Button);
        JButton Card2Button = new JButton("Exit");
        card2.add(Card2Button);

        cards.add(card1, "C1");
        cards.add(card2, "C2");

        f.add(cards, BorderLayout.CENTER);

        f.setTitle("Furutsu");
        f.setSize(500, 300);
        f.setLocationRelativeTo(null);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setVisible(true);
    }

然后你可以直接参考它：

@Override
public void actionPerformed(ActionEvent e) {
    // now you can call methods on your cardLayout variable:
    cardLayout.show(...);  // I'll leave it to you to figure out what to put in here
}

有关CardLayout的更多信息，请查看其tutorial

请注意，如果您只想按向前或向后的顺序交换组件，请查看CardLayout的其他方法，例如next(cards)和previous(cards)