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问题描述
我创建了一个程序，允许用户选择餐厅菜单项并添加每个项目的总和，为每个人创建一个双餐总和.我还需要在每次输入一个新人时添加每顿饭(使用 Next Person 按钮)以得出我创建为 ArrayList 的 tableTotal.我似乎无法让数组列表添加的不仅仅是最后一个人的膳食总计.我需要它来包含每个人的膳食总和，即，如果有 4 个人，我的 tableTotal ArrayList 将包含 4 个唯一值.从这里开始，我将添加 tableTotal 中的所有值以得出整个表的双精度值.任何有关如何将每个人的 mealTotal 放入我的 tableTotal ArrayList 的帮助将不胜感激！
I have created a program that allows a user to choose restaurant menu items and adds the total of each item creating a double mealTotal for each person. I need to also add each mealTotal every time a new person is entered(using the Next Person button) to come up with the tableTotal which I have created as an ArrayList. I cannot seem to get the arraylist to add more than just the last person's mealTotal. I need it to include every person's mealTotal, i.e., if there were 4 people, my tableTotal ArrayList would hold 4 unique values. From here, I would add all of the values in tableTotal to come up with a double value for the entire table. Any help in how to put each person's mealTotal into my tableTotal ArrayList would be much appreciated!
这里是主类:
import javax.swing.BoxLayout;
import javax.swing.JFrame;
public class MenuApp extends JFrame {
// static JFrame frame;
public static void main(String args[]) {
JFrame aFrame = new MenuApp();
aFrame.setVisible(true);
}
public MenuApp() {
setTitle("Leah Thompson's Restaurant App");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Buttons buttonPanel = new Buttons();
buttonPanel.setLayout(new BoxLayout(buttonPanel, BoxLayout.Y_AXIS));
setContentPane(buttonPanel);
pack();
}
}
还有按钮类:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.JTextField;
import java.util.ArrayList;
public class Buttons extends JPanel {
private final JTextField nameField;
String[] drinkChoice = {"Coke", "Beer", "Wine"};
String[] appChoice = {"Soup", "Salad", "Brie"};
String[] entreeChoice = {"Pasta", "Steak", "Burger"};
String[] dessertChoice = {"Tiramisu", "Cheesecake", "Chocolate Cake"};
JRadioButton[] drinkButtons = new JRadioButton[drinkChoice.length];
JRadioButton[] appButtons = new JRadioButton[appChoice.length];
JRadioButton[] entreeButtons = new JRadioButton[entreeChoice.length];
JRadioButton[] dessertButtons = new JRadioButton[dessertChoice.length];
ButtonGroup buttonGroupDrink = new ButtonGroup();
ButtonGroup buttonGroupApp = new ButtonGroup();
ButtonGroup buttonGroupEntree = new ButtonGroup();
ButtonGroup buttonGroupDessert = new ButtonGroup();
JButton mealCost;
JButton nextPerson;
JButton submitOrder;
ArrayList<Double> tableTotal = new ArrayList(0);
double mealTotal = 0;
double mealTotal1 = 0;
public Buttons(){
ActionListener nameEntered = new NameEntered();
add(new JLabel("Name (hit enter after typing name)"));
nameField = new JTextField(10);
add(nameField);
nameField.addActionListener(nameEntered);
ActionListener drinkSelection = new DrinkSelectionChangeMade();
ActionListener appSelection = new AppSelectionChangeMade();
ActionListener entreeSelection = new EntreeSelectionChangeMade();
ActionListener dessertSelection = new DessertSelectionChangeMade();
add(new JLabel("Choose a Drink"));
for (int i = 0; i < drinkChoice.length; i++) {
drinkButtons[i] = new JRadioButton(drinkChoice[i]);
drinkButtons[i].getModel().setActionCommand(drinkChoice[i]);
drinkButtons[i].addActionListener(drinkSelection);
buttonGroupDrink.add(drinkButtons[i]);
add(drinkButtons[i]);
// if (i == 0) {
// mealTotal = mealTotal + 2;
// } else if (i == 1) {
// mealTotal = mealTotal + 3;
// } else {
// mealTotal = mealTotal + 5;
// }
}
add(new JLabel("Choose an Appetizer"));
for (int i = 0; i < appChoice.length; i++) {
appButtons[i] = new JRadioButton(appChoice[i]);
appButtons[i].getModel().setActionCommand(appChoice[i]);
appButtons[i].addActionListener(appSelection);
buttonGroupApp.add(appButtons[i]);
add(appButtons[i]);
// if (i == 0) {
// mealTotal = mealTotal + 6;
// } else if (i == 1) {
// mealTotal = mealTotal + 7;
// } else {
// mealTotal = mealTotal + 8;
// }
}
add(new JLabel("Choose an Entree"));
for (int i = 0; i < entreeChoice.length; i++) {
entreeButtons[i] = new JRadioButton(entreeChoice[i]);
entreeButtons[i].getModel().setActionCommand(entreeChoice[i]);
entreeButtons[i].addActionListener(entreeSelection);
buttonGroupEntree.add(entreeButtons[i]);
add(entreeButtons[i]);
// if (i == 0) {
// mealTotal = mealTotal + 12;
// } else if (i == 1) {
// mealTotal = mealTotal + 20;
// } else {
// mealTotal = mealTotal + 10;
// }
}
add(new JLabel("Choose a Dessert"));
for (int i = 0; i < dessertChoice.length; i++) {
dessertButtons[i] = new JRadioButton(dessertChoice[i]);
dessertButtons[i].getModel().setActionCommand(dessertChoice[i]);
dessertButtons[i].addActionListener(dessertSelection);
buttonGroupDessert.add(dessertButtons[i]);
add(dessertButtons[i]);
// if (i == 0) {
// mealTotal = mealTotal + 7;
// } else if (i == 1) {
// mealTotal = mealTotal + 6;
// } else {
// mealTotal = mealTotal + 5;
// }
}
mealCost = new JButton("Total Cost of Meal");
add(mealCost);
ActionListener mealPrice = new MealCostPressed();
mealCost.addActionListener(mealPrice);
nextPerson = new JButton("Next Person");
add(nextPerson);
ActionListener next = new NextPersonPressed();
nextPerson.addActionListener(next);
submitOrder = new JButton("Submit Order");
add(submitOrder);
ActionListener submit = new SubmitPressed();
submitOrder.addActionListener(submit);
//tableTotal.add(mealTotal);
//add(new JLabel("Your total is: " + mealTotal));
}
private class NameEntered implements ActionListener{
@Override
public void actionPerformed(ActionEvent e){
String name = nameField.getText();
System.out.println(name);
}
}
private class DrinkSelectionChangeMade implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
String drink = buttonGroupDrink.getSelection().getActionCommand();
System.out.println(drink + " as a drink");
if(drink == "Coke"){
mealTotal = mealTotal + 1.95;
}
else if(drink == "Beer"){
mealTotal = mealTotal + 2.95;
}
else{
mealTotal = mealTotal + 4.95;
}
}
}
private class AppSelectionChangeMade implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
String app = buttonGroupApp.getSelection().getActionCommand();
System.out.println(app + " as an appetizer");
if(app == "Soup"){
mealTotal = mealTotal + 3.95;
}
else if(app == "Salad"){
mealTotal = mealTotal + 4.95;
}
else{
mealTotal = mealTotal + 7.95;
}
}
}
private class EntreeSelectionChangeMade implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
String entree = buttonGroupEntree.getSelection().getActionCommand();
System.out.println(entree + " as an entree");
if(entree == "Pasta"){
mealTotal = mealTotal + 11.95;
}
else if(entree == "Steak"){
mealTotal = mealTotal + 19.95;
}
else{
mealTotal = mealTotal + 9.95;
}
}
}
private class DessertSelectionChangeMade implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
String dessert = buttonGroupDessert.getSelection().getActionCommand();
System.out.println(dessert + " as a dessert");
if(dessert == "Tiramisu"){
mealTotal = mealTotal + 6.95;
}
else if(dessert == "Cheesecake"){
mealTotal = mealTotal + 5.95;
}
else{
mealTotal = mealTotal + 4.95;
}
tableTotal.add(mealTotal);
}
}
private class NextPersonPressed implements ActionListener{
@Override
public void actionPerformed(ActionEvent e){
//removeAll();
JFrame nextFrame = new MenuApp();
nextFrame.setVisible(true);
System.out.println("Next Customer: ");
}
}
private class MealCostPressed implements ActionListener{
@Override
public void actionPerformed(ActionEvent e){
JOptionPane.showMessageDialog(mealCost, mealTotal);
}
}
private class SubmitPressed implements ActionListener{
@Override
public void actionPerformed(ActionEvent e){
JOptionPane.showMessageDialog(nextPerson, "Thank you for your order. Please Exit Now.");
System.out.println("The total cost for the table is: " + tableTotal);
}
}
}
推荐答案
您的问题是您正在为每个人创建一个新的 MenuApp 对象，并且每个 MenuApp 对象都有自己的 tableTotal 字段.
Your problem is that you're creating a new MenuApp object for each person, and each MenuApp object has its own tableTotal field.
可能的解决方案:
- 只为每个新人创建一个 MenuApp 对象并更改其状态，可能是 JLabel 上的文本.
- 或者，如果您绝对必须为每个人创建一个新的 MenuApp，那么这样做，将它放在一个模态 JDialog 中，而不是一个 JFrame 中，当对话框完成时，调用代码查询它的总数，然后添加它到 tableTotal 字段.
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