title: Dynamic Combo box issue
body: <p>Hi I'm using a table which two columns namely instrument and method. On click of a button, I'll add a row with the combo box as an editor in each cell. Also, those combo box wil have the actionlistener. Like when I'm selecting instrument, method combo box list should be changed. I'm using only two combo box and I'm instantiating it every time when I add a row. My problem is whenever I add a new row, the existing rows combos are getting reloaded with the latest value. That means, the combo boxes are unique even though I'm instantiating it differently. What is the way to create the combo box dynamically which should have the values of its own. Posting my code below for your reference. </p>
  
  <pre><code>addItem.addActionListener(new ActionListener() {
  
          public void actionPerformed(ActionEvent arg0) {
              comboInstrument = new CeNComboBox();
              comboMethod = new CeNComboBox();
              TableColumn instrumentColumn = table.getColumn("Instrument Used");
              TableColumn methodColumn = table.getColumn("Method Title");
              comboInstrument.removeAllItems();
              listInstruments = analyticalUtil.getInstruments(listAnalysisSummaryPrefs);
              iterateInstruments = listInstruments.iterator();
              while(iterateInstruments.hasNext()){
                  comboInstrument.addItem(iterateInstruments.next());
              }
              dtm.addRow(new Object[]{" "," "});
              comboInstrument.setEditable(true);
              instrumentColumn.setCellEditor(new MyComboBoxEditor(comboInstrument));
              instrumentColumn.setCellRenderer(new MyComboBoxRenderer());
              comboMethod.setEditable(true);
              methodColumn.setCellEditor(new MyComboBoxEditor(comboMethod));
              methodColumn.setCellRenderer(new MyComboBoxRenderer());
  
              comboInstrument.addActionListener(new ActionListener(){
                  public void actionPerformed(ActionEvent argEvent){
                      comboInstrumentActionPerformed();
                  }
              });
              comboMethod.addActionListener(new ActionListener(){
                  public void actionPerformed(ActionEvent argEvent){
                      comboMethodActionPerformed();
                  }
              });
          }
      });
  </code></pre>
  
  <p>MyComboBoxEditor.java</p>
  
  <pre><code>public class MyComboBoxEditor extends DefaultCellEditor {
  
  
  
      public MyComboBoxEditor(JComboBox combobox) {
          super(combobox);
      }
  }
  </code></pre>
  
  <p>I'm very new to Swing. Please help me out. </p>
  
  <p>Adding some sample code with hardcoded values. If you run this you will understand my problem. Test in this way. 
       1. Select a value from first column, first row and select value from another column. 
       2. Do the same in second row and now check the second column of first row. All the values will be reloaded based on the selection made for the second row. 
  This is the problem I'm facing. The below code copied and edited from the following link 
    <a href="https://stackoverflow.com/questions/6539001/jcombobox-action-listener">JComboBox Action listener</a></p>
  
  <pre><code>private static final long serialVersionUID = 1L;
          private JComboBox mainComboBox;
          private JComboBox subComboBox;
          private Hashtable&lt;Object, Object&gt; subItems = new Hashtable&lt;Object, Object&gt;();
  
          public Testing() {
              String[] items = {"","Select Item", "Color", "Shape", "Fruit", "Size"};
              mainComboBox = new JComboBox(items);
              mainComboBox.addActionListener(this);
              mainComboBox.addItemListener(this);
              mainComboBox.setEditable(true);
              //prevent action events from being fired when the up/down arrow keys are used
              //mainComboBox.putClientProperty("JComboBox.isTableCellEditor", Boolean.TRUE);
  //          getContentPane().add(mainComboBox, BorderLayout.WEST);
              subComboBox = new JComboBox();//  Create sub combo box with multiple models
              subComboBox.setPrototypeDisplayValue("XXXXXXXXXX"); // JDK1.4
              subComboBox.addItemListener(this);
  //          getContentPane().add(subComboBox, BorderLayout.CENTER);
              String[] subItems1 = {"Select Color", "Red", "Blue", "Green"};
              subItems.put(items[1], subItems1);
              String[] subItems2 = {"Select Shape", "Circle", "Square", "Triangle"};
              subItems.put(items[2], subItems2);
              String[] subItems3 = {"Select Fruit", "Apple", "Orange", "Banana"};
              subItems.put(items[3], subItems3);
              String[] subItems4 = {"Select Size", "Big", "Middle", "Small"};
              subItems.put(items[4], subItems4);
              DefaultTableModel model = new DefaultTableModel(new String[]{"Instrument Used","Method Title"},0);
              JTable table = new JTable(model);
              table.getColumn("Instrument Used").setCellEditor(new MyComboBoxEditor(mainComboBox));
              table.getColumn("Instrument Used").setCellRenderer(new MyComboBoxRenderer());
              table.getColumn("Method Title").setCellEditor(new MyComboBoxEditor(subComboBox));
              table.getColumn("Method Title").setCellRenderer(new MyComboBoxRenderer());
              model.addRow(new String[]{""});
              model.addRow(new String[]{""});
              getContentPane().add(table, BorderLayout.CENTER);
          }
  
          public void actionPerformed(ActionEvent e) {
              String item = (String) mainComboBox.getSelectedItem();
              JOptionPane.showMessageDialog(null, "Action Performed "+item);
              Object o = subItems.get(item);
              if (o == null) {
                  subComboBox.setModel(new DefaultComboBoxModel());
              } else {
                  subComboBox.setModel(new DefaultComboBoxModel((String[]) o));
              }
          }
  
          public void itemStateChanged(ItemEvent e) {
              if (e.getStateChange() == ItemEvent.SELECTED) {
                  if (e.getSource() == mainComboBox) {
                      if (mainComboBox.getSelectedIndex() != 0) {
                          FirstDialog firstDialog = new FirstDialog(Testing.this,
                                  mainComboBox.getSelectedItem().toString(), "Please wait,  Searching for ..... ");
                      }
                  } 
              }
          }
  
          private class FirstDialog extends JDialog {
  
              private static final long serialVersionUID = 1L;
  
              FirstDialog(final Frame parent, String winTitle, String msgString) {
                  super(parent, winTitle);
                  //setModalityType(Dialog.ModalityType.APPLICATION_MODAL);
                  JLabel myLabel = new JLabel(msgString);
                  JButton bNext = new JButton("Stop Processes");
                  add(myLabel, BorderLayout.CENTER);
                  add(bNext, BorderLayout.SOUTH);
                  bNext.addActionListener(new ActionListener() {
  
                      public void actionPerformed(ActionEvent evt) {
                          setVisible(false);
                      }
                  });
                  javax.swing.Timer t = new javax.swing.Timer(1000, new ActionListener() {
  
                      public void actionPerformed(ActionEvent e) {
                          setVisible(false);
                      }
                  });
                  t.setRepeats(false);
                  t.start();
                  setLocationRelativeTo(parent);
                  setSize(new Dimension(400, 100));
                  setVisible(true);
              }
          }
  
          public static void main(String[] args) {
              JFrame frame = new Testing();
              frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
              frame.pack();
              frame.setLocationRelativeTo(null);
              frame.setVisible(true);
          }
  </code></pre>