loginframe.java

购物车模块实例。购物车模块可以浏览商品类别；可以根据商品类别浏览商品信息；可以购买商品；可以查看购物车的商品；可以修改购买商品的数量和删除购买的商品。

package cartinterface;

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

public class LoginFrame extends JFrame implements ActionListener {
  JPanel contentPane;
  JLabel jLabel1 = new JLabel();
  JTextField jTextField1 = new JTextField();
  JButton jButton1 = new JButton();
  JButton jButton2 = new JButton();
  //创建字体类
  Font dialog13 = new java.awt.Font("Dialog", 0, 13);

  public LoginFrame() {
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  private void jbInit() throws Exception  {
    contentPane = (JPanel) this.getContentPane();
    contentPane.setLayout(null);
    this.setSize(new Dimension(400, 300));
    this.setTitle("购物车登陆窗口");
    jLabel1.setText("顾客名字：");
    jLabel1.setBounds(new Rectangle(72, 79, 79, 29));
    jLabel1.setFont(dialog13);
    jTextField1.setBounds(new Rectangle(193, 83, 141, 22));
    jTextField1.setFont(dialog13);
    jButton1.setText("商品浏览窗口");
    jButton1.setActionCommand("cartApp");
    jButton1.setBounds(new Rectangle(72, 161, 127, 25));
    jButton1.setFont(dialog13);
    jButton1.addActionListener(this);
    jButton2.setText("退出");
    jButton2.setActionCommand("exit");
    jButton2.setBounds(new Rectangle(207, 161, 127, 25));
    jButton2.setFont(dialog13);
    jButton2.addActionListener(this);
    contentPane.add(jButton2, null);
    contentPane.add(jButton1, null);
    contentPane.add(jTextField1, null);
    contentPane.add(jLabel1, null);
  }
  protected void processWindowEvent(WindowEvent e) {
    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
      System.exit(0);
    }
  }
  //按钮单击事件
  public void actionPerformed(ActionEvent e) {
    //取得按钮的动作字符串
    String actionCommand = e.getActionCommand().trim();
    //单击按钮的处理代码
    if (actionCommand.equals("cartApp")) {
      //取得顾客的名字
      String name = jTextField1.getText();
      if(name.trim().length() == 0){
        JOptionPane.showMessageDialog(null, "请输入顾客的名字");
        return;
      }
      //创建购物车类
      Cart cart = new Cart();
      //设置顾客的名字
      cart.setCustomer(name);
      //创建窗口类
      CartFrame frame = new CartFrame(cart);
      Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
      Dimension frameSize = frame.getSize();
      if (frameSize.height > screenSize.height) {
        frameSize.height = screenSize.height;
      }
      if (frameSize.width > screenSize.width) {
        frameSize.width = screenSize.width;
      }
      //使窗口居中对齐
      frame.setLocation((screenSize.width - frameSize.width) / 2,
                        (screenSize.height - frameSize.height) / 2);
      frame.setVisible(true);

    }else if(actionCommand.equals("exit")){
      System.exit(0);
    }
  }
}