Java Swing Examples: Add, Remove, Sort Elements in JList using JOptionPane - Internet & Web Programming Lab

Java Swing Example: Add, Remove, Sort Elements in JList using JOptionPane

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Source code:

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

/*
 * sw4.java
 *
 * Created on 21 Nov, 2011, 8:11:19 PM
 */

package swingexamples;

import java.util.Enumeration;
import javax.swing.DefaultListModel;
import javax.swing.JOptionPane;

/**
 *
 * @author nn
 */
public class sw4 extends javax.swing.JFrame {
    DefaultListModel dm;
    /** Creates new form sw4 */
    public sw4() {
        initComponents();
        jList1.setModel(dm=new DefaultListModel());
    }

    /** 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">//GEN-BEGIN:initComponents
    private void initComponents() {

        jScrollPane1 = new javax.swing.JScrollPane();
        jList1 = new javax.swing.JList();
        jButton1 = new javax.swing.JButton();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jScrollPane1.setViewportView(jList1);

        jButton1.setText("ADD");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        });

        jButton2.setText("REMOVE");
        jButton2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton2ActionPerformed(evt);
            }
        });

        jButton3.setText("SORT");
        jButton3.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton3ActionPerformed(evt);
            }
        });

        jLabel1.setFont(new java.awt.Font("DejaVu Sans", 1, 14)); // NOI18N
        jLabel1.setText("JList");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(35, 35, 35)
                        .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 140, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(52, 52, 52)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, 74, Short.MAX_VALUE)
                            .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                            .addComponent(jButton3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))
                    .addGroup(layout.createSequentialGroup()
                        .addGap(86, 86, 86)
                        .addComponent(jLabel1)))
                .addContainerGap(47, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(71, 71, 71)
                        .addComponent(jButton1)
                        .addGap(32, 32, 32)
                        .addComponent(jButton2)
                        .addGap(36, 36, 36)
                        .addComponent(jButton3))
                    .addGroup(layout.createSequentialGroup()
                        .addGap(17, 17, 17)
                        .addComponent(jLabel1)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 240, javax.swing.GroupLayout.PREFERRED_SIZE)))
                .addContainerGap(27, Short.MAX_VALUE))
        );

        pack();
    }// </editor-fold>//GEN-END:initComponents

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton1ActionPerformed
        // TODO add your handling code here:
        dm.addElement(JOptionPane.showInputDialog("Enter an element to add"));
    }//GEN-LAST:event_jButton1ActionPerformed

    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton2ActionPerformed
        // TODO add your handling code here:
        Object s[]=jList1.getSelectedValues();
        for(int i=0;i<s.length;i++)
           dm.removeElement(s[i]);
       
    }//GEN-LAST:event_jButton2ActionPerformed

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton3ActionPerformed
        // TODO add your handling code here:
      Object temp;
      Object ob[]= dm.toArray();
      int n=ob.length;
      for(int i=0;i<n;i++)
          for(int j=0;j<n-i-1;j++)
          {
            if(ob[j].toString().compareTo(ob[j+1].toString())>0) // used to sort strings
            //    if(Integer.parseInt(ob[j].toString()) > Integer.parseInt(ob[j+1].toString())) used to sort ineger numbers
                
            {
             temp=ob[j];
             ob[j]=ob[j+1];
             ob[j+1]=temp;
            }

          }
    dm.removeAllElements();
    for(int i=0;i<n;i++)
      dm.addElement(ob[i]);
    }//GEN-LAST:event_jButton3ActionPerformed

    /**
    * @param args the command line arguments
    */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new sw4().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JList jList1;
    private javax.swing.JScrollPane jScrollPane1;
    // End of variables declaration//GEN-END:variables

}

Note: In the source code < is replaced with "&lt;" for syntax highlighting.