我正在寻求帮助来调试我编写的这个程序，没有错误，但目标是创建一个框架，其中包含三个面板，每个面板都有一个标题边框。我遇到了困难，因为我的提示要求我创建 2 个构造函数和 2 个类，所以当我在 main 中调用 DailySales 类时，我觉得它不包括其他类。
所以基本上我怎样才能在保持两个类和两个构造函数的同时显示面板，以及如何为每个 JPanel 添加标题边框，抱歉，我在 Oracle 教程中遇到了困难。
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class DailySales extends JPanel {
final int lPizzaPrice = 12;
final int mPizzaPrice = 9;
final int sPizzaPrice = 6;
final int bSticksPrice = 3;
final double tax = .06;
final int dailyOper = 1000;
String lPizza;
String mPizza;
String sPizza;
String bSticks;
int largePizza;
int mediumPizza;
int smallPizza;
int breadSticks;
int totalLargePizza;
int totalMediumPizza;
int totalSmallPizza;
int totalBreadSticks;
int totalSales;
double totalTax;
double netSales;
int operCost;
double profit;
private FlowLayout dailyFlow;
private Container container;
JLabel lPizzaLabel = new JLabel("Large Pizza");//creating labels
JLabel mPizzaLabel = new JLabel("Medium Pizza");
JLabel sPizzaLabel = new JLabel("Small Pizza");
JLabel bSticksLabel = new JLabel("Bread Sticks");
JLabel totalSalesLabel = new JLabel("Total Sales");
JLabel totalTaxLabel = new JLabel("Total Tax");
JLabel netSalesLabel = new JLabel("Net Sales");
JLabel dailyCostLabel = new JLabel("Daily Oper Cost");
JLabel profitLabel = new JLabel("Profit or Loss");
JTextField largeField = new JTextField(10);
JTextField mediumField = new JTextField(10);
JTextField smallField = new JTextField(10);
JTextField breadField = new JTextField(10);
JTextField totalLargeField = new JTextField(10);
JTextField totalMediumField = new JTextField(10);
JTextField totalSmallField = new JTextField(10);
JTextField totalBreadField = new JTextField(10);
JTextField totalSalesField = new JTextField(10);
JTextField totalTaxField = new JTextField(10);
JTextField netSalesField = new JTextField(10);
JTextField dailyCostField = new JTextField(10);
JTextField profitField = new JTextField(10);
JButton clearButton = new JButton("Clear Fields");//Creating buttons
JButton calculateButton = new JButton("Calculate");
JButton exitButton = new JButton("Exit");
JPanel subPanel1 = new JPanel();
JPanel subPanel2 = new JPanel();
JPanel subPanel3 = new JPanel();
JPanel top = new JPanel();
public class GUI extends JPanel {
public GUI() {
subPanel1.setLayout(dailyFlow);
subPanel1.add(lPizzaLabel, largeField);
subPanel1.add(mPizzaLabel, mediumField);
subPanel1.add(sPizzaLabel, smallField);
subPanel1.add(bSticksLabel, breadField);
subPanel1.setSize(100, 100);
subPanel2.setLayout(dailyFlow);
subPanel2.add(totalLargeField);
subPanel2.add(totalMediumField);
subPanel2.add(totalSmallField);
subPanel2.add(totalBreadField);
subPanel3.setLayout(dailyFlow);
subPanel3.add(totalSalesLabel, totalSalesField);
subPanel3.add(totalTaxLabel, totalTaxField);
subPanel3.add(netSalesLabel, netSalesField);
subPanel3.add(dailyCostLabel, dailyCostField);
subPanel3.add(profitLabel, profitField);
top.setBackground(Color.red);
JLabel title = new JLabel("Eve's Pizza Daily Sales");
title.setFont(new Font("Helvetica", 1, 14));
top.add(title);
totalSalesField.setEditable(false);//making total field uneditable
totalTaxField.setEditable(false);
netSalesField.setEditable(false);
dailyCostField.setEditable(false);
profitField.setEditable(false);
}
}
public DailySales() //creating a constructor
{
/**
* The constructor with all the layout informations and operators
*
*
* Also adding all labels, textfields, and buttons to frame. making the
* total field uneditable
*/
JFrame frame = new JFrame();
frame.add(subPanel1);
frame.add(subPanel2);
frame.add(subPanel3);
frame.add(top);
frame.setSize(600, 450);
frame.setVisible(true);
clearButton.addActionListener(new ActionListener() {//initial button removes all entered text
public void actionPerformed(ActionEvent e) {
largeField.setText("");
mediumField.setText("");
smallField.setText("");
breadField.setText("");
totalLargeField.setText("");
totalMediumField.setText("");
totalSmallField.setText("");
totalBreadField.setText("");
totalSalesField.setText("");
totalTaxField.setText("");
netSalesField.setText("");
dailyCostField.setText("");
profitField.setText("");
}
});
calculateButton.addActionListener(new ActionListener() {//update button calculates all the inputs and displays everything
public void actionPerformed(ActionEvent e) {
lPizza = largeField.getText();
mPizza = mediumField.getText();
sPizza = smallField.getText();
bSticks = breadField.getText();
largePizza = Integer.parseInt(lPizza);
mediumPizza = Integer.parseInt(mPizza);
smallPizza = Integer.parseInt(sPizza);
breadSticks = Integer.parseInt(bSticks);
totalLargePizza = (lPizzaPrice * largePizza);
totalMediumPizza = (mPizzaPrice * mediumPizza);
totalSmallPizza = (sPizzaPrice * smallPizza);
totalBreadSticks = (bSticksPrice * breadSticks);
totalLargeField.setText("" + totalLargePizza);
totalMediumField.setText("" + totalMediumPizza);
totalSmallField.setText("" + totalSmallPizza);
totalBreadField.setText("" + totalBreadSticks);
totalSales = (totalLargePizza + totalMediumPizza + totalSmallPizza + totalBreadSticks);
totalTax = (totalSales * tax);
netSales = (totalSales - totalTax);
profit = (netSales - dailyOper);
/**
* calculates total by adding all entered values if else
* statements for different situations that calculate the
* different between total and diet
*/
if (profit > 0) {
profitLabel.setText("Profit of ");
} else if (profit < 0) {
profitLabel.setText("Loss of ");
} else if (profit == 0) {
profitLabel.setText("No profit or loss ");
}
if (largePizza < 0) {
JOptionPane.showMessageDialog(null, "Quantity muist be >=0");
} else if (mediumPizza < 0) {
JOptionPane.showMessageDialog(null, "Quantity muist be >=0");
} else if (smallPizza < 0) {
JOptionPane.showMessageDialog(null, "Quantity muist be >=0");
} else if (breadSticks < 0) {
JOptionPane.showMessageDialog(null, "Quantity muist be >=0");
}
}
});
exitButton.addActionListener(new ActionListener() {//close button closes the program when clicked on
@Override
public void actionPerformed(ActionEvent e) {
System.exit(0);
}
});
}
public static void main(String[] args) {
new DailySales();
}
}