List.java Source code

Introduction

Here is the source code for List.java

Source

// : c14:List.java
// <applet code=List width=250 height=375></applet>
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// www.BruceEckel.com. See copyright notice in CopyRight.txt.

import java.awt.Color;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.DefaultListModel;
import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JTextArea;
import javax.swing.border.Border;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class List extends JApplet {
    private String[] flavors = { "Chocolate", "Strawberry", "Vanilla Fudge Swirl", "Mint Chip",
            "Mocha Almond Fudge", "Rum Raisin", "Praline Cream", "Mud Pie" };

    private DefaultListModel lItems = new DefaultListModel();

    private JList lst = new JList(lItems);

    private JTextArea t = new JTextArea(flavors.length, 20);

    private JButton b = new JButton("Add Item");

    private ActionListener bl = new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            if (count < flavors.length) {
                lItems.add(0, flavors[count++]);
            } else {
                // Disable, since there are no more
                // flavors left to be added to the List
                b.setEnabled(false);
            }
        }
    };

    private ListSelectionListener ll = new ListSelectionListener() {
        public void valueChanged(ListSelectionEvent e) {
            if (e.getValueIsAdjusting())
                return;
            t.setText("");
            Object[] items = lst.getSelectedValues();
            for (int i = 0; i < items.length; i++)
                t.append(items[i] + "\n");
        }
    };

    private int count = 0;

    public void init() {
        Container cp = getContentPane();
        t.setEditable(false);
        cp.setLayout(new FlowLayout());
        // Create Borders for components:
        Border brd = BorderFactory.createMatteBorder(1, 1, 2, 2, Color.BLACK);
        lst.setBorder(brd);
        t.setBorder(brd);
        // Add the first four items to the List
        for (int i = 0; i < 4; i++)
            lItems.addElement(flavors[count++]);
        // Add items to the Content Pane for Display
        cp.add(t);
        cp.add(lst);
        cp.add(b);
        // Register event listeners
        lst.addListSelectionListener(ll);
        b.addActionListener(bl);
    }

    public static void main(String[] args) {
        run(new List(), 250, 375);
    }

    public static void run(JApplet applet, int width, int height) {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add(applet);
        frame.setSize(width, height);
        applet.init();
        applet.start();
        frame.setVisible(true);
    }
} ///:~