// box-handling
function openBox(id, trigger) {
 var box = document.getElementById(id);
 //alert ("openbox");
 if(box.style.display != "block"){
 box.style.display = "block";
 }
}

function closeBox(id, trigger) {
 var box = document.getElementById(id);
// alert ("closebox");
 if(box.style.display != "none"){
 box.style.display = "none";
 }
}

function checkBoxHandler(id,trigger, boxid){
	var checkbox = document.getElementById(id);
	if (checkbox.checked){
		//alert ("Handler: closebox");
		openBox(boxid, trigger);
	}else{
		//alert ("Handler: closebox");
		closeBox(boxid, trigger);
	}
} 

function addLoadEvent(func) {
    var oldonload = window.onload;
    if (typeof window.onload != 'function') {
        window.onload = func;
    } else {
        window.onload = function() {
            if (oldonload) {
                oldonload();
            }
            func();
        }
    }
}