CardLayout 在 Java 中显示空白 JPanel

Question

我搜索了不同的教程并查看了 CardLayout 和 JPanel 的 Class 配置文件，但我似乎无法显示我的 window。目前它会打开一个具有适当尺寸和标题但实际容器中没有任何内容的框架。

这是我的代码（P.S。我知道这很乱）

import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.IOException;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.Clip;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.UnsupportedAudioFileException;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;

public class Casino extends JFrame implements ActionListener {

    private JButton start, settings, scenario, music;


    /**
     * Constructor method
     */

    public Casino(){

        JPanel mainUI, startUI, settingsUI, scenarioUI, blackjackUI, oddorevenUI, tcmUI, overorunderUI, slotsUI;
        JPanel menus = new JPanel(new CardLayout());


        CardLayout GUI = (CardLayout) menus.getLayout();
        mainUI = new JPanel();
        getContentPane().add(mainUI);
        mainUI.setBackground(new Color(53, 9, 9));

        //Background items
        JLabel title = new JLabel(new ImageIcon("title.png"));
        title.setBounds(0,-280,780,700);
        mainUI.add(title);

        JLabel border = new JLabel(new ImageIcon("mainscreenborder.png"));
        border.setBounds(0, 180, 780, 700);
        mainUI.add(border);

        //Main menu buttons
        settings = new JButton();
        ImageIcon s = new ImageIcon("settings-button.png");
        settings.setBounds(320, 200, 122, 63);
        settings.setIcon(s);
        mainUI.add(settings);

        music = new JButton();
        ImageIcon m = new ImageIcon("music-button.png");
        music.setBounds(320, 268, 122, 63);
        music.setBackground(new Color(53, 9, 9));
        music.setIcon(m);
        mainUI.add(music);

        scenario = new JButton();
        ImageIcon sc = new ImageIcon("scenario-button.png");
        scenario.setBounds(320, 336, 122, 63);
        scenario.setBackground(new Color(53, 9, 9));
        scenario.setIcon(sc);
        mainUI.add(scenario);

        start = new JButton();
        ImageIcon st = new ImageIcon("start-button.png");
        start.setBounds(320, 404, 122, 63);
        start.setBackground(new Color(53, 9, 9));
        start.setIcon(st);
        mainUI.add(start);


        menus.add(mainUI, "Main Menu");

        GUI.show(menus, "Main Menu");




        setSize(780, 700);
        setResizable(false);
        setLayout(GUI);
        setTitle("White Lily Casino");
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setVisible(true);
    }

    public void actionPerformed(ActionEvent e){

    }

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        Casino wlc = new Casino();

    }
}

注意：以前当我使用 Container c 方法而不是使用 JPanel 和 CardLayout 时它起作用了。我现在正在尝试将其切换为卡片布局，因为我想使用按钮导航到多个屏幕

Answer 1

尝试将 mainUI 添加到 JFrame

getContentPane().add(mainUI)

或

add(mainUI)

CardLayout 在 Java 中显示空白 JPanel

CardLayout showing blank JPanel in Java

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