function getElementsByClassName(className, element) {
    element = element ? element : document;

    var muster = new RegExp("(^|\\s)" + className + "(\\s|$)");
    var alles = element.getElementsByTagName("*");
    var gefunden = new Array();
    var i;

    for (i = 0; i < alles.length; i++) {
        if (alles[i] && alles[i].className && alles[i].className != "") {
            if (alles[i].className.match(muster))
                gefunden[gefunden.length] = alles[i];
        }
    }

    return gefunden;
}

function handleCheckboxes(trigger, checkboxClass) {
	checkboxContainer = document.getElementById('media_input');
	checkboxes = getElementsByClassName(checkboxClass, checkboxContainer);	
	var status;
	if (trigger.checked == false) {
		status = false;
	} else {
		status = true;
	}	
	for (i = 0; i < checkboxes.length; i++) {		
		checkboxes[i].checked = status;		
    }
}

function adaptSelectAllCheckbox(trigger) {	
	if (trigger.checked == false) {
		selectAllCheckbox = document.getElementById('selectAllCheckboxes');
		if (selectAllCheckbox.checked == true) {
			selectAllCheckbox.checked = false;
		}
	}
}