Need to set a double value depending on which item(s) are selected from a JList.

Question

My code so far:

import java.awt.BorderLayout;
import java.awt.Container;
import javax.swing.Box;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class TestFile2 {

    public static void main(String args[]) {
        String size[] = {"Small", "Medium", "Large", "Extra Large"};
        String toppings[] = {"Cheese", "Pepperoni", "Sausage", "Spinach", "Pepperoncini"};
        JFrame f = new JFrame("Pizza");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JList list1 = new JList(size);
        JList list2 = new JList(toppings);
        Container c = f.getContentPane();
        JScrollPane sp1 = new JScrollPane(list1);
        sp1.setColumnHeaderView(new JLabel("Select Size"));
        JScrollPane sp2 = new JScrollPane(list2);
        sp2.setColumnHeaderView(new JLabel("Select Toppings. Hold Ctrl to select multiple toppings"));
        Box box = Box.createHorizontalBox();
        box.add(sp1);
        box.add(sp2);
        list1.addListSelectionListener(new ListSelectionListener() {

            public void valueChanged(ListSelectionEvent e) {
                JList jListSource = (JList) e.getSource();
                Object[] selection = jListSource.getSelectedValues();
                if (!e.getValueIsAdjusting()) {
                    System.out.println("----");
                    for (int i = 0; i < selection.length; i++) {
                        double costSize;
                        if (selection[i].equals("Small")) {
                            costSize = 7.00;
                        } else if (selection[i].equals("Medium")) {
                            costSize = 9.00;
                        } else if (selection[i].equals("Large")) {
                            costSize = 11.00;
                        } else {
                            costSize = 14.00;
                        }
                        System.out.println("selection = " + selection[i]);
                        System.out.println("selection = " + costSize);
                    }
                }
            }
        });
        c.add(box, BorderLayout.CENTER);
        f.setSize(
                300, 200);
        f.setVisible(
                true);
    }
}

I need to do something similar to what I did with list1.

I need to have the user select from a JList both the size of pizza and the toppings. At the end I need to be able to calculate the total cost. Each topping is $1. Any point in a certain direction would be greatly appreciated as I have been pulling my hair out for the past few hours trying different methods for this problem.

Thanks in advance.

Answer 1

I hope this will help :) ... there are other ways to do it.... this just one of them ...

import java.awt.BorderLayout;
import java.awt.Container;
import javax.swing.Box;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class TestFile2 {

    private static JList list1;
    private static JList list2;

    public static void main(String args[]) {
        String size[] = {"Small", "Medium", "Large", "Extra Large"};
        String toppings[] = {"Cheese", "Pepperoni", "Sausage", "Spinach", "Pepperoncini"};
        JFrame f = new JFrame("Pizza");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        list1 = new JList(size);
        list2 = new JList(toppings);
        Container c = f.getContentPane();
        JScrollPane sp1 = new JScrollPane(list1);
        sp1.setColumnHeaderView(new JLabel("Select Size"));
        JScrollPane sp2 = new JScrollPane(list2);
        sp2.setColumnHeaderView(new JLabel("Select Toppings. Hold Ctrl to select multiple toppings"));
        Box box = Box.createHorizontalBox();
        box.add(sp1);
        box.add(sp2);
        list1.addListSelectionListener(new ListSelectionListener() 
        {

            public void valueChanged(ListSelectionEvent e)
            {
                handleEvent(e);
            }
        });
        list2.addListSelectionListener(new ListSelectionListener() 
        {

            public void valueChanged(ListSelectionEvent e)
            {
                handleEvent(e);
            }
        });
        c.add(box, BorderLayout.CENTER);
        f.setSize(
                300, 200);
        f.setVisible(
                true);
    }

    protected static void handleEvent(ListSelectionEvent e) 
    {

        double cost = 0.0;
         Object[] selection = list1.getSelectedValues();
         Object[] toppings = list2.getSelectedValues();

         if(toppings.length == 0)
             System.out.println("Please select a topping");

         if(selection.length == 0)
             System.out.println("Please select a size");

         if (!e.getValueIsAdjusting()) 
         {
             System.out.println("----");
             for (int i = 0; i < selection.length; i++) 
             {
                 double costSize;
                 if (selection[i].equals("Small")) {
                    cost = 7.00;
                 } else if (selection[i].equals("Medium")) {
                    cost = 9.00;
                 } else if (selection[i].equals("Large")) {
                    cost = 11.00;
                 } else {
                    cost = 14.00;
                 }

             }


             for (int i = 0; i < toppings.length; i++) 
             {
                cost++;
             }


             System.out.println("Total = " + cost);
         }

    }
}

Answer 2

Favonius is right, the answer runs OK.