/* přepnutí CLASS u elementů */
function SwitchClass(boxID) {
    var oEl = document.getElementById(boxID);        
    toggleClass(oEl, "collapsed");
}

/* vlozi/vyhodi sClassName, vrati true pokud vlozil a false pokud vyhodil */
function toggleClass(oEl, sClassName){
	if (null == oEl){return false;}
    var bRet;
    var sTmp = oEl.className;
    if (sTmp.indexOf(sClassName) >= 0){
        sTmp = sTmp.replace(sClassName, "");
        sTmp = sTmp.replace(/^[ ]*/, "");
        sTmp = sTmp.replace(/[ ]*$/, "");
        bRet = false;
    }
    else{
        sTmp = sTmp + " " + sClassName;
        bRet = true;
    }
    oEl.className = sTmp;
    return bRet;
}