Re: JList index

Dirk Bruere at NeoPax wrote:


Just tested... works for me... both programatically and in the
properties window (I assume Matisse in NetBeans, yes?)

One thing I noticed is that the index starts with 0. So to select item
x, use x-1 in the setSelectedIndex method. Same for properties window.

Code below... it's auto generated and I didn't complete all the buttons,
but it runs and the input field works.

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

/*
 * SwingTest.java
 *
 * Created on Apr 22, 2009, 8:25:10 PM
 */
package fubar;

import javax.swing.JOptionPane;

/**
 *
 * @author Brenden
 */
public class SwingTest extends javax.swing.JFrame
{
    /** Creates new form SwingTest */
    public SwingTest()
    {
        initComponents();
    }

    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    @SuppressWarnings( "unchecked" )
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        jScrollPane1 = new javax.swing.JScrollPane();
        jList1 = new javax.swing.JList();
        nextButton = new javax.swing.JButton();
        previousButton = new javax.swing.JButton();
        clearButton = new javax.swing.JButton();
        quitButton = new javax.swing.JButton();
        selectItemField = new javax.swing.JTextField();
        jLabel1 = new javax.swing.JLabel();
        jMenuBar1 = new javax.swing.JMenuBar();
        jMenu1 = new javax.swing.JMenu();
        jMenu2 = new javax.swing.JMenu();

setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

jPanel1.setBorder(javax.swing.BorderFactory.createTitledBorder("Random
List"));

        jList1.setModel(new javax.swing.AbstractListModel() {
            String[] strings = { "Item 1", "Item 2", "Item 3", "Item 4",
"Item 5" };
            public int getSize() { return strings.length; }
            public Object getElementAt(int i) { return strings[i]; }
        });
        jList1.setSelectedIndex(3);
        jScrollPane1.setViewportView(jList1);

        javax.swing.GroupLayout jPanel1Layout = new
javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(

jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jScrollPane1,
javax.swing.GroupLayout.DEFAULT_SIZE, 134, Short.MAX_VALUE)
                .addContainerGap())
        );
        jPanel1Layout.setVerticalGroup(

jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

            .addGroup(jPanel1Layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jScrollPane1,
javax.swing.GroupLayout.DEFAULT_SIZE, 202, Short.MAX_VALUE)
                .addContainerGap())
        );

        nextButton.setText("Next");

        previousButton.setText("Previous");

        clearButton.setText("Clear");
        clearButton.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                clearButtonActionPerformed(evt);
            }
        });

        quitButton.setText("Quit");

        selectItemField.addActionListener(new
java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                selectItemFieldActionPerformed(evt);
            }
        });

        jLabel1.setText("Select Item:");

        jMenu1.setText("File");
        jMenuBar1.add(jMenu1);

        jMenu2.setText("Edit");
        jMenuBar1.add(jMenu2);

        setJMenuBar(jMenuBar1);

        javax.swing.GroupLayout layout = new
javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(

layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jPanel1,
javax.swing.GroupLayout.PREFERRED_SIZE,
javax.swing.GroupLayout.DEFAULT_SIZE,
javax.swing.GroupLayout.PREFERRED_SIZE)

.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)

                    .addGroup(layout.createSequentialGroup()
                        .addGap(64, 64, 64)

.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

                            .addComponent(nextButton)
                            .addComponent(previousButton)
                            .addComponent(clearButton)
                            .addComponent(jLabel1)
                            .addComponent(selectItemField,
javax.swing.GroupLayout.PREFERRED_SIZE, 102,
javax.swing.GroupLayout.PREFERRED_SIZE))
                        .addContainerGap(58, Short.MAX_VALUE))
                    .addGroup(layout.createSequentialGroup()

.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(quitButton)
                        .addContainerGap())))
        );

        layout.linkSize(javax.swing.SwingConstants.HORIZONTAL, new
java.awt.Component[] {clearButton, nextButton, previousButton,
quitButton});

        layout.setVerticalGroup(

layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()

.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

.addGroup(javax.swing.GroupLayout.Alignment.TRAILING,
layout.createSequentialGroup()
                        .addComponent(jLabel1)

.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(selectItemField,
javax.swing.GroupLayout.PREFERRED_SIZE,
javax.swing.GroupLayout.DEFAULT_SIZE,
javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(18, 18, 18)
                        .addComponent(nextButton)

.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(previousButton)
                        .addGap(18, 18, 18)
                        .addComponent(clearButton)
                        .addGap(15, 15, 15)
                        .addComponent(quitButton))
                    .addComponent(jPanel1,
javax.swing.GroupLayout.Alignment.TRAILING,
javax.swing.GroupLayout.DEFAULT_SIZE,
javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                .addContainerGap())
        );

        pack();
    }// </editor-fold>

    private void
selectItemFieldActionPerformed(java.awt.event.ActionEvent evt)
    {
        int index;
        try {
            index = Integer.parseInt( selectItemField.getText() );
        }
        catch( NumberFormatException n ) {
            JOptionPane.showMessageDialog( this,
                    "Oops, couldn't parse that." );
            return;
        }
        jList1.setSelectedIndex( index );
    }

    private void clearButtonActionPerformed(java.awt.event.ActionEvent evt)
    {
        jList1.clearSelection();
    }

    /**
     * @param args the command line arguments
     */
    public static void main( String args[] )
    {
        java.awt.EventQueue.invokeLater( new Runnable()
        {
            public void run()
            {
                new SwingTest().setVisible( true );
            }
        } );
    }

    // Variables declaration - do not modify
    private javax.swing.JButton clearButton;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JList jList1;
    private javax.swing.JMenu jMenu1;
    private javax.swing.JMenu jMenu2;
    private javax.swing.JMenuBar jMenuBar1;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JButton nextButton;
    private javax.swing.JButton previousButton;
    private javax.swing.JButton quitButton;
    private javax.swing.JTextField selectItemField;
    // End of variables declaration
}