卡片布局 java 运行时错误

Question

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class Choice extends JDialog{
    private JPanel panelMain;
    private JButton btnPurchase;
    private JButton btnRefund;
    private JPanel cards;

    final static String MainPage = "Main Page";
    final static String PurchasePage = "Purchase Page";
    final static String RefundPage = "Refund Page";

    public Choice() {
        setContentPane(panelMain);
        setModal(true);
        //getRootPane().setDefaultButton(buttonOK);
        cards = new JPanel(new CardLayout());
        cards.add(new Choice().ChoiceGUI(), MainPage);
        cards.add(new Purchase().PurchaseGUI(), PurchasePage);
        final CardLayout cl = (CardLayout) cards.getLayout();
        cl.show(cards, MainPage);

        btnPurchase.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                cl.show(cards, PurchasePage);
            }
        });
        btnRefund.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                //refund click function
            }
        });
    }
    public JPanel ChoiceGUI (){
        return panelMain;
    }
    public static void main(String[] args){
        Choice dialog = new Choice();
        dialog.pack();
        dialog.setVisible(true);
        System.exit(0);
    }

}

那是 Choice.java 下面是 Purchase.java

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class Purchase extends Choice{
    private JPanel panelPurchase;
    private JLabel lblamnt;
    private JButton btn1;
    private JButton btn2;
    private JButton btn3;
    private JButton btn4;
    private JButton btn5;
    private JButton btn6;
    private JButton btn7;
    private JButton btn8;
    private JButton btn9;
    private JButton btn0;
    private JButton btnClear;
    private JButton btnSubmit;

    /*
    public Purchase(){
        btn1.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "1");
            }
        });
        btn2.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "2");
            }
        });
        btn3.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "3");
            }
        });
        btn4.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "4");
            }
        });
        btn5.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "5");
            }
        });
        btn6.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "6");
            }
        });
        btn7.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "7");
            }
        });
        btn8.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "8");
            }
        });
        btn9.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "9");
            }
        });
        btn0.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText(lblamnt.getText() + "0");
            }
        });
        btnClear.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                lblamnt.setText("");
            }
        });
        btnSubmit.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                //run code to confirm and show next screen to display current currency exchange.
            }
        });
    }
    */
    public JPanel PurchaseGUI(){
        return panelPurchase;
    }
}

我收到大量重复错误。我还在学习如何使用卡片布局。

程序运行时出现这些错误。它编译得很好。

Exception in thread "main" java.lang.WhosebugError
at java.awt.Window.init(Window.java:507)
at java.awt.Window.<init>(Window.java:436)
at java.awt.Window.<init>(Window.java:591)
at java.awt.Dialog.<init>(Dialog.java:665)
at java.awt.Dialog.<init>(Dialog.java:409)
at javax.swing.JDialog.<init>(JDialog.java:272)
at javax.swing.JDialog.<init>(JDialog.java:206)
at javax.swing.JDialog.<init>(JDialog.java:154)

at src.Choice.<init>(Choice.java:18)

at src.Choice.<init>(Choice.java:23) (repeating)

Exception in thread "main" Exception in thread "main"

我重做了 purchase.java 以包含一个 GETTER

并且 Choice.java 错误位于

public Choice() {

和...

cards.add(new Choice().ChoiceGUI(), MainPage);

我做错了什么？卡在这里一整天都没有进展

我正在尝试设置它，所以当我按下购买按钮时，它会在同一个 window.

中加载购买表格

Answer 1

看到没有人回答这个问题，我不得不弄清楚。我做了卡片布局，不得不更改设计。

卡片布局 java 运行时错误

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intellij-idea

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