Question

对于我在Java类中的第二次编程任务，我们必须创建一个Pizza Shop菜单GUI。所有内容都出现在我的GUI上（包括选项，框，单选按钮等），除了您应该单击以计算总成本的按钮（“过程选择”）。以下是我的代码：

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

public class PizzaShop extends JFrame {

    private Topping t;
    private PizzaSize ps;
    private PizzaType pt;
    private JPanel buttonPanel;
    private JButton ProcessSelection;

    public PizzaShop() {
        super("Welcome To Home Pizza Shop");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new BorderLayout());
        t = new Topping();
        ps = new PizzaSize();
        pt = new PizzaType();
        createPanel();
        add(t, BorderLayout.NORTH);
        add(ps, BorderLayout.WEST);
        add(pt, BorderLayout.CENTER);
        setVisible(true);
    }

    private void createPanel() {
        buttonPanel = new JPanel();
        ProcessSelection = new JButton("Process Selection");
        ProcessSelection.addActionListener(new calButton());
        buttonPanel.add(ProcessSelection);
    }

    private class calButton implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            double subtotal;
            subtotal = t.getTopping() + ps.getPizzaSize();
            JOptionPane.showMessageDialog(null, "Your Order \n" + "Pizza Type" + pt.getPizzaType() + "\n" + "Amount Due" + subtotal);
        }
    }

    private class ExitButtonListener implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            System.exit(0);
        }
    }
}

我忘了在某处添加一些代码吗？我很难过。

Answer 1

您没有将buttonPanel添加到主视图

更新：您应该这样做：

private void createPanel() {
    buttonPanel = new JPanel();
    ProcessSelection = new JButton("Process Selection");
    ProcessSelection.addActionListener(new calButton());
    buttonPanel.add(ProcessSelection);
    add(buttonPanel, BorderLayout.SOUTH);
}

Answer 2

您需要将按钮面板添加到框架中：

add(buttonPanel, BorderLayout.SOUTH);

Answer 3

将您的createPanel（）更改为：

private JPanel createPanel() {
    buttonPanel = new JPanel();
    ProcessSelection = new JButton("Process Selection");
    ProcessSelection.addActionListener(new calButton());
    buttonPanel.add(ProcessSelection);
    return buttonPanel;
 }

并将以下代码添加到您的PizzaShop（）方法中：

add(createPanel(), BorderLayout.SOUTH);

或者你可以按照Adel Boutros所说的那样。

按钮没有出现在Swing GUI中

3 个答案: