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
}