function ShowCalendar(calendar)
{
    HideAllCalendars();
    
    var cal = document.getElementById(calendar);
    var btncal = document.getElementById('btnCal');
    
    cal.style.left = getElementLeft(btncal) + "px";
    cal.style.top = (getElementTop(btncal) + 24) + "px";
    cal.style.display = "block";
}

function ToggleCalendar(calendar)
{
    var cal = document.getElementById(calendar);
    if (cal.style.display == "block")
        cal.style.display = "none";
    else
        ShowCalendar(calendar);
}

function HideAllCalendars()
{
    var cals = getElementsByClassName("realCalendar");
    for (i = 0; i < cals.length; i++)
        cals[i].style.display = "none";
}