A question on Grids

Question

Hi, I hope you can help me with this.
I would like to construct a grid using Swing, which will form the base area for a cellular automation. Therefore, I need to be able to retain information on each cell of the grid.
Any idea on how to do this?
Thanks in advance.
PW

Answer 1

Hi,
Hi, I hope you can help me with this.
I would like to construct a grid using Swing, which
will form the base area for a cellular automation.
Therefore, I need to be able to retain information on
each cell of the grid.
Any idea on how to do this?
Thanks in advance.
PWAre you talking about cellular automaton, as in "Conway's Life"?
If that's the case, don't use JTable. It's for displaying tabular data. I would recommend writing a custom JPanel subclass that paints the grid and the cells.
Here's a start on the painting part. Running this application will bring up a frame with a grid on it. A single cell will be painted in yellow (top left) and it will change every half-second.
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class CellPanel extends JPanel {
    boolean first = true;
    Timer timer = new Timer(500, new ActionListener() {
        public void actionPerformed(ActionEvent ae) {
            calculateNextStage();
            repaint();
    public CellPanel() {
        setBackground(Color.WHITE);
    private void calculateNextStage() {
        first = !first;
    public void start() {
        timer.start();
    public void stop() {
        timer.stop();
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        for (int i = 20; i < getWidth(); i += 20) {
            g.drawLine(i, 0, i, getHeight());
        for (int i = 20; i < getHeight(); i += 20) {
            g.drawLine(0, i, getWidth(), i);
        g.setColor(Color.YELLOW);
        if (first) {
            g.fillRect(0, 0, 20, 20);
        } else {
            g.fillRect(21, 21, 19, 19);
    public Dimension getPreferredSize() {
        return new Dimension(400, 400);
    public static void main(String[] args) {
        JFrame f = new JFrame("CellPanel");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        CellPanel cp = new CellPanel();
        f.setContentPane(cp);
        f.setResizable(false);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
        cp.start();
}Hope this helps :)
Shannon Hickey (Swing Team)