Java Swing 实现购物小程序的代码

以下是一个简单的购物小程序的 Java Swing 代码示例：

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

public class ShoppingApp extends JFrame implements ActionListener {
    private static final long serialVersionUID = 1L;
    private JLabel title, item1, item2, item3, item4, totalPrice;
    private JTextField qty1, qty2, qty3, qty4;
    private JButton buyButton;

    public ShoppingApp() {
        setTitle("Shopping App");
        setLayout(new GridLayout(6, 2));

        title = new JLabel("Welcome to Shopping App");
        title.setFont(new Font("Serif", Font.BOLD, 20));
        add(title);

        item1 = new JLabel("Item 1 (Price $10):");
        add(item1);
        qty1 = new JTextField();
        add(qty1);

        item2 = new JLabel("Item 2 (Price $15):");
        add(item2);
        qty2 = new JTextField();
        add(qty2);

        item3 = new JLabel("Item 3 (Price $20):");
        add(item3);
        qty3 = new JTextField();
        add(qty3);

        item4 = new JLabel("Item 4 (Price $25):");
        add(item4);
        qty4 = new JTextField();
        add(qty4);

        buyButton = new JButton("Buy");
        add(buyButton);
        buyButton.addActionListener(this);

        totalPrice = new JLabel();
        add(totalPrice);

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(400, 300);
        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        int total = 0;
        int item1Qty = Integer.parseInt(qty1.getText());
        int item2Qty = Integer.parseInt(qty2.getText());
        int item3Qty = Integer.parseInt(qty3.getText());
        int item4Qty = Integer.parseInt(qty4.getText());

        total += item1Qty * 10;
        total += item2Qty * 15;
        total += item3Qty * 20;
        total += item4Qty * 25;

        totalPrice.setText("Total Price: $" + total);
    }

    public static void main(String[] args) {
        new ShoppingApp();
    }
}

这个程序具有一个简单的 GUI 界面，它包括四个商品和购买按钮。当用户点击购买按钮时，程序将计算所有商品的数量和总价，并将其显示在标签上。