What is the best way to implement a 2D grid of radio buttons?

Question

What is the best way to implement a 2D grid of radio buttons so that only one option in each column and one option in each row can be selected?

Answer 1

A 1D array of 1D arrays of radio buttons. Each row (or column) would use the normal radio button functionality, while each column (or row) would be updated by a loop called whenever an individual radio button is toggled.

Answer 2

Something like this?

using System;
using System.Drawing;
using System.Windows.Forms;

class Program {

    static RadioButton[] bs = new RadioButton[9];

    static void HandleCheckedChanged (object o, EventArgs a) {
        RadioButton b = o as RadioButton;
        if (b.Checked) {
            Console.WriteLine(Array.IndexOf(bs, b));
        }
    }

    static void Main () {
        Form f = new Form();
        int x = 0;
        int y = 0;
        int i = 0;
        int n = bs.Length;
        while (i < n) {
            bs[i] = new RadioButton();
            bs[i].Parent = f;
            bs[i].Location = new Point(x, y);
            bs[i].CheckedChanged += new EventHandler(HandleCheckedChanged);
            if ((i % 3) == 2) {
                x = 0;
                y += bs[i].Height;
            } else {
                x += bs[i].Width;
            }
            i++;
        }
        Application.Run(f);
    }

}

Regards, tamberg

Answer 3

You could approach this with a custom collection and databind the radio buttons.

Each individual child would have a property for row and a property for column as well as the true/false value flag, which raises an event when changed to true via a click or keypress.

Logic in the collection class would respond to the value change and loop through the other children in the same row and column to notify them that they should be false.

If you don't want to databind, you could also do it with a collection of user controls.