试图让 cardLayout 工作

Question

我想要做的就是设置卡片布局样式按钮。从理论上讲，您应该点击按钮，然后另一个（在本例中）名称会出现，直到完成。（当用户要关闭时）

我有这个，我觉得它应该完全有效，但是 JGrasp 给我一个错误：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class JDisappearingFriends extends JFrame implements ActionListener
{
   private JButton intro = new JButton("Click to see Friends!");
   private JButton nb = new JButton("Mini Vinny");
   private JButton sb = new JButton("Makayla");
   private JButton eb = new JButton("Aurora");
   private JButton wb = new JButton("Alyssa");
   private JButton cb = new JButton("And My Bestest Friend: SAMMY!!");
   CardLayout cardLayout = new CardLayout();
   public JDisappearingFriends()
   {
      setLayout(new CardLayout());
      add("Click to see Friends!", intro);
      add("MiniVinny", nb);
      add("Makayla", sb);
      add("Aurora", eb);
      add("Alyssa", wb);
      add("And Finally My Best Friend Sammy!", cb);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      intro.addActionListener(this);
      nb.addActionListener(this);
      sb.addActionListener(this);
      eb.addActionListener(this);
      wb.addActionListener(this);
   }
   public void actionPreformed(ActionEvent e)
   {
      cardLayout.next(getContentPane());
   }
   public static void main(String[] args)
   {
      JDisappearingFriends jbl = new JDisappearingFriends();
      jbl.setSize(400, 400);
      jbl.setVisible(true);
   }
}

当我尝试编译时，收到一条错误消息，如下所列：

JDisappearingFriends.java:8: error: JDisappearingFriends is not abstract and does not override abstract method actionPerformed(ActionEvent) in ActionListener

public class JDisappearingFriends 扩展 JFrame 实现 ActionListener ^ 如果有人可以给我提示，将不胜感激！！

Answer 1

您的错误消息很好地说明了问题所在：

JDisappearingFriends.java:8: error: JDisappearingFriends is not abstract and does not override abstract method actionPerformed(ActionEvent) in ActionListener

actionPreformed 拼错了，应该是 actionPerformed

你也应该习惯使用 @Override 注释

@Override
public void actionPreformed(ActionEvent e)
{
    cardLayout.next(getContentPane());
}

这在您重写其他方法时会有所帮助类并提供编译时间保护以确保您不会不小心拼错方法名称

您还应该在 EDT 的上下文中创建您的 UI。有关详细信息，请参阅 Initial Threads。

试图让 cardLayout 工作

Attempting to get cardLayout to work

java

swing

awt

layout-manager

cardlayout