// JavaScript Document
function fetch_object(idname)
{
    var my_obj = document.getElementById(idname);
    return my_obj;
}
function toggle_button(obj)
{
    for (i = 1; i<= 7; i++  )
    {
        
        var button_img = fetch_object("button_" + i);
        var sub_button = fetch_object("sub_button_" + i);
        var sub_button_index =  fetch_object("sub_button_0");
        sub_button_index.style.display = "none";
        if (obj == i)
        {
            button_img.src = "image/button_" + i + "_on.gif";
            sub_button.style.display = "block";
        }
        else
        {
            button_img.src = "image/button_" + i + ".gif";
            sub_button.style.display = "none";
        }
    }
}