How to use JCombobox (using ComboboxModel) in JTable?

Question

I have a question first, let imagine that i have 2 tables: Location(IDLocation, Place), Employee(ID, Name, Location)
And I get all data in Location table into ArrayList, then setup a model (that extends ComboboxModel) and use this arraylist.
After that i get all data in Employee table into Arraylist, then setup a MyTableModel (that extends AbstractTableModel) and use this arraylist.
I could setup combobox in Location column, but i just wonder that how do i know how many comboboxes i need?. And if i use one model for all of these comboboxed and when i change selected item in one combobox, it will change data in other comboboxes in other rows. :(
Anybody helps me, please?

Answer 1

you just need only one combobox as the editor for all cell in location column.
because, initially, all the cell in location column is "rendered" as non-combobox, the combobox appears only when you edit one cell, so you use only one combobox for every edition of a cell (in location column).
The way to do this is to setCellEditor of your JTable to (new DefaultCellEditor(editComboBox)), so that every time you click on a cell (in location column), the combobox appears and your selected value will be the new value in that cell, all you have to do is just set the CellEditor as combobox, java 's done the rest for you.
http://java.sun.com/docs/books/tutorial/uiswing/components/table.html#combobox : perfect in this situation
import javax.swing.DefaultCellEditor;
import javax.swing.JComboBox;
public class TableComboBox extends javax.swing.JFrame {
    public TableComboBox() {
     initComponents();
    private void initComponents() {
        scrollPane = new javax.swing.JScrollPane();
        myTable = new javax.swing.JTable();
        getContentPane().setLayout(new java.awt.FlowLayout());
        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        // create a table
        myTable.setModel(new javax.swing.table.DefaultTableModel(
            new Object [][] {
                {"E01", "John Bolton", "Boston"},
                {"E02", "Vannessa", "Ohio"},
                {"E03", "Hellboy", "Alaska"}
            new String [] {
                "ID", "Name", "Location"
        // create a combobox which model will be created from the database as the editor
        JComboBox locations = new JComboBox(new String[]{"Boston", "Ohio", "Alaska"});
        // create a default cell editor
        DefaultCellEditor editor = new DefaultCellEditor(locations);
        // set that cell editor as the location column cells editor (column number 2 is location column), then use setCellEditor() method
        myTable.getColumnModel().getColumn(2).setCellEditor(editor);
        scrollPane.setViewportView(myTable);
        getContentPane().add(scrollPane);
        java.awt.Dimension screenSize = java.awt.Toolkit.getDefaultToolkit().getScreenSize();
        setBounds((screenSize.width-380)/2, (screenSize.height-117)/2, 380, 117);
    public static void main(String args[]) {
     java.awt.EventQueue.invokeLater(new Runnable() {
         public void run() {
          new TableComboBox().setVisible(true);
    private javax.swing.JTable myTable;
    private javax.swing.JScrollPane scrollPane;
}Edited by: bobbi2004 on Oct 28, 2008 9:59 AM