function at_show_aux(parent, child)
{
    var p = document.getElementById(parent);
    var c = document.getElementById(child );

    var top  = (c["at_position"] == "y") ? p.offsetHeight+2 : 0;
    var left = (c["at_position"] == "x") ? p.offsetWidth +2 : 0;

    for (; p; p = p.offsetParent)
    {
        top  += p.offsetTop;
        left += p.offsetLeft;
    }
    //alert(left);
    c.style.position   = "absolute";
    c.style.top        = top +'px';
    c.style.left       = left - 2 +'px';
    c.style.visibility = "visible";
}

// ***** at_show *****

function at_show()
{
    var p = document.getElementById(this["at_parent"]);
    var c = document.getElementById(this["at_child"]);

    at_show_aux(p.id, c.id);
    clearTimeout(c["at_timeout"]);
}

// ***** at_hide *****

function at_hide()
{
    //var p = document.getElementById(this["at_parent"]);
    var c = document.getElementById(this["at_child"]);

    c["at_timeout"] = setTimeout("document.getElementById('" + c.id + "').style.visibility = 'hidden'", 1);
}

// ***** at_click *****

function at_click()
{
    var p = document.getElementById(this["at_parent"]);
    var c = document.getElementById(this["at_child" ]);

    if (c.style.visibility != "visible") 
        at_show_aux(p.id, c.id); 
    else 
        c.style.visibility = "hidden";
        
    return false;
}

// ***** at_attach *****

// PARAMETERS:
// parent   - id of the parent html element
// child    - id of the child  html element that should be droped down
// showtype - "click" = drop down child html element on mouse click
//            "hover" = drop down child html element on mouse over
// position - "x" = display the child html element to the right
//            "y" = display the child html element below
// cursor   - omit to use default cursor or specify CSS cursor name

function at_attach(parent, child, showtype, position, cursor)
{
    var p = document.getElementById(parent);
    var c = document.getElementById(child);

    p["at_parent"]     = p.id;
    c["at_parent"]     = p.id;
    p["at_child"]      = c.id;
    c["at_child"]      = c.id;
    p["at_position"]   = position;
    c["at_position"]   = position;

    c.style.position   = "absolute";
    c.style.visibility = "hidden";

    if (cursor != undefined) 
        p.style.cursor = cursor;

    switch (showtype)
    {
        case "click":
            p.onclick     = at_click;
            p.onmouseout  = at_hide;
            c.onmouseover = at_show;
            c.onmouseout  = at_hide;
            break;
        case "hover":
            p.onmouseover = at_show;
            p.onmouseout  = at_hide;
            c.onmouseover = at_show;
            c.onmouseout  = at_hide;
            break;
    }
}