/* Event capture to disable context menu */
if (document.layers){
	document.captureEvents(Event.MOUSEDOWN);
	document.onmousedown=clickNS4;
} else if (document.all&&!document.getElementById){
	document.onmousedown=clickIE4;
}

document.oncontextmenu=new Function("return false")


/* image handling functions */
function setImageChecked (image) {
	image.src='images/icon_active.gif'
}

function setImageUnchecked (image) {
	image.src='images/icon_inactive.gif'
}

function setImageMouseover (image, field, desired_value) {
//	alert('hallo ' + field.value + ' ' + desired_value);

	if (field.value==desired_value) {
		setImageChecked(image);
	} else {
		image.src='images/icon_over.gif';
	}
}

function setImageMouseout (image, field, desired_value) {
//	alert(field.value + ' value: ' + desired_value);
	if (field.value==desired_value) {
		setImageChecked(image);
	} else {
		setImageUnchecked(image);
	}
}


function resetCheckboxes (filter) {
	for (i=0; i < document.images.length; i++) {
		var myname = document.images[i].name;
		if (myname.indexOf(filter)==0) {
			setImageUnchecked(document.images[i]);
		}

 	}

}

function checkOrUncheck(field, value) {
	var imageName = field.name + '_' + value;
 	// Set if not value present, otherwiese reset.
	if (field.value=='') {
		field.value = value;
		setImageChecked(document.images[imageName]);
	} else {
		field.value = '';
		setImageUnchecked(document.images[imageName]);
	}

}

function checkCheckbox(field, value) {
	var imageName = field.name + '_' + value;

	field.value = value;
	setImageChecked(document.images[imageName]);

}

	/* Preload Images */
	function newImage(arg) {
		if (document.images) {
			rslt = new Image();
			rslt.src = arg;
			return rslt;
		}
	}
	
	function changeImages() {
		if (document.images && (preloadFlag == true)) {
			for (var i=0; i<changeImages.arguments.length; i+=2) {
				document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
			}
		}
	}
	
	var preloadFlag = false;
	
	    function preloadImages() {
	      if (document.images) {
	        checkBox_checked_image = newImage("images/icon_active.gif");
	        checkBox_checked_grey_image = newImage("images/icon_active.gif");
	        checkBox_over_image = newImage("images/icon_over.gif");
	        checkBox_unchecked_image = newImage("images/icon_inactive.gif");
	        preloadFlag = true;
	      }
	    }