在我添加了十几个按钮后，并不是所有的按钮都出现了。我做错了什么？

Question

    JButton button_one=new JButton();
    button_one.setPreferredSize(new Dimension(100,150));
    mainpanel.add(button_one);
    button_one.addActionListener(new ActionListener(){
        
        @Override
        public void actionPerformed(ActionEvent button_1_picked){
            amount_of_cards_picked=amount_of_cards_picked+1;
            cardamountcheck();
            if(twocardspicked==true){
                userpick2=0;
                System.out.println(setoutcards[userpick2]);
                pairdetermination();
            }
            else if(twocardspicked==false){
                userpick1=0;
                System.out.println(setoutcards[userpick1]);
                
            }
        }
    });
    
    JButton button_two = new JButton();
    button_two.setPreferredSize(new Dimension(100, 150));
    mainpanel.add(button_two);
    button_two.addActionListener(new ActionListener(){
        
        @Override
        public void actionPerformed(ActionEvent button_2_picked){
            amount_of_cards_picked=amount_of_cards_picked+1;
            cardamountcheck();
            if(twocardspicked==true){
                userpick2=1;
                System.out.println(setoutcards[userpick2]);
                pairdetermination();
            }
            else if(twocardspicked==false){
                userpick1=1;
                System.out.println(setoutcards[userpick1]);
                
            }
        }
    });

基本上，当点击其中一个按钮时，代码中的变量就会发生变化。这些按钮运行良好，完全符合我的要求，但当按钮超过13个时，它们不会全部出现，我需要52个。

Answer 1

我想在JPanel中添加52个按钮。所有的人都是ActionListeners。

完成。我创建了一个GUI，显示52个JButtons。我把它们做成了OP的一半大小，这样GUI就更适合回答问题了。

这是完整的可运行代码。一个最小的可复制的例子。

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class FiftyTwoJButtonGUI implements Runnable {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new FiftyTwoJButtonGUI());
    }

    @Override
    public void run() {
        JFrame frame = new JFrame("52 JButton GUI");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        frame.add(createMainPanel(), BorderLayout.CENTER);
        
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }
    
    private JPanel createMainPanel() {
        JPanel panel = new JPanel(new GridLayout(0, 13, 5, 5));
        panel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
        
        CardListener listener = new CardListener();
        
        for (int i = 0; i < 52; i++) {
            JButton button = new JButton("" + (i + 1));
            button.addActionListener(listener);
            button.setPreferredSize(new Dimension(50, 75));
            panel.add(button);
        }
        
        return panel;
    }
    
    public class CardListener implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent event) {
            JButton button = (JButton) event.getSource();
            int cardNumber = Integer.valueOf(button.getText());
            System.out.println(cardNumber);
        }
        
    }

}