List.java

//: c13:List.java
// From 'Thinking in Java, 2nd ed.' by Bruce Eckel
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
// <applet code=List width=250
// height=375> </applet>
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.border.*;
import com.bruceeckel.swing.*;

public class List extends JApplet {
  String[] flavors = { "Chocolate", "Strawberry",
    "Vanilla Fudge Swirl", "Mint Chip",
    "Mocha Almond Fudge", "Rum Raisin",
    "Praline Cream", "Mud Pie" };
  DefaultListModel lItems=new DefaultListModel();
  JList lst = new JList(lItems);
  JTextArea t = new JTextArea(flavors.length,20);
  JButton b = new JButton("Add Item");
  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);
      }
    }
  };
  ListSelectionListener ll =
    new ListSelectionListener() {
      public void valueChanged(
        ListSelectionEvent e) {
          t.setText("");
          Object[] items=lst.getSelectedValues();
          for(int i = 0; i < items.length; i++)
            t.append(items[i] + "\n");
        }
    };
  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) {
    Console.run(new List(), 250, 375);
  }
} ///:~