function OpenVenster(waarheen,breedte,hoogte){
	DetailVenster = window.open(waarheen,'Detail','toolbar=no,location=no,directories=no,status=no,scrollbars=yes,resizeable=yes,width='+breedte+',height='+hoogte);
	DetailVenster.focus();
}

function maximizeWindow(WindowObj){
	if (parseInt(navigator.appVersion)>3){
		if (navigator.appName=="Netscape"){
			if(WindowObj.screenX>0 || WindowObj.screenY>0) WindowObj.moveTo(0,0);
			if(WindowObj.outerWidth < screen.availWidth) WindowObj.outerWidth=screen.availWidth;
			if(WindowObj.outerHeight < screen.availHeight) WindowObj.outerHeight=screen.availHeight;
		} else {
			WindowObj.moveTo(-4,-4);
			WindowObj.resizeTo(screen.availWidth+8,screen.availHeight+8);
		}
	}
}


function NieuwVenster(waarheen){
	DetailVenster = window.open(waarheen,'Detail','toolbar=yes,location=yes,directories=yes,status=yes,scrollbars=yes,resizeable=yes,width=800,height=600');
	DetailVenster.focus();
}

/// controleer opacity afhandeling voor browser
function ChkOpacityType(ObjectNaam){

	var browsertype;

	holderobject=document.getElementById(ObjectNaam);

	if(typeof holderobject.style.MozOpacity != 'undefined'){
		browsertype = 'moz';
	} else if(typeof holderobject.style.KhtmlOpacity != 'undefined'){
		browsertype = 'khtml';
	} else if(typeof holderobject.filters == 'object'){
		browsertype = (holderobject.filters.length > 0 && typeof holderobject.filters.alpha == 'object' && typeof holderobject.filters.alpha.opacity == 'number') ? 'ie' : 'none';
	} else if(typeof holderobject.style.opacity != 'undefined'){
		browsertype = 'w3c';
	} else {
		browsertype = 'none';
	}

	return browsertype;
}


function ZetAlpha(ObjectNaam,percentage){

	obj=document.getElementById(ObjectNaam);

	if(percentage > 0){

		alpha=percentage/100;

		var type = typeof chkbrowser == 'undefined' ? ChkOpacityType(ObjectNaam) : chkbrowser;

		switch(type){

			case 'ie' :	if (typeof obj.filters == 'object' && obj.filters.alpha){
						obj.filters.alpha.opacity = percentage;
					}  else {
						 obj.style.filter='alpha('+percentage+')';
					}
					break;

			case 'khtml' :	obj.style.KhtmlOpacity = alpha;
					break;

			case 'moz' :	obj.style.MozOpacity = (alpha >= 0.99 ? 0.99 : alpha);//Max opacity to prevent flicker in firefox
					break;

			case 'none' :	break;

			default : 	obj.style.opacity = (alpha >= 0.99 ? 0.99 : alpha);//Max opacity to prevent flicker in firefox

		}
		obj.style.display = '';
	} else {
		obj.style.display = 'none';
	}
}

function SchakelStijl(ObjNaam,stijl){
	alert(ObjNaam);
	alert(stijl);
	document.getElementById(ObjNaam).className=stijl;
}

function SchakelImg(ObjNaam,plaatje){
	document.getElementById(ObjNaam).src=plaatje;
}

function numbersonly(myfield, e, dec){

	var key;
	var keychar;

	if(window.event){
		key = window.event.keyCode;
	} else if(e){
		key = e.which;
	} else {
		return true;
	}

	keychar = String.fromCharCode(key);

	// control keys
	if(key==null || key==0 || key==8 || key==9 || key==13 || key==27){
		return true;
	} else if((("0123456789").indexOf(keychar) > -1)){// numbers
		return true;
	} else {
		return false;
	}
}


//Image preload routines staan hieronder
function ImagePreloader(images, callback){

	this.callback = callback;// store the callback

	this.nLoaded = 0;
	this.nProcessed = 0;
	this.aImages = new Array;
 
	this.nImages = images.length;

	for(var i=0; i < images.length; i++){// for each image, call preload()
		this.preload(images[i]);
	}
}


ImagePreloader.prototype.preload = function(image){

	// create new Image object and add to array
	//var oImage = new Image;
	var oImage = document.createElement("img"); // met new Image() werkt 't zeker niet!

	this.aImages.push(oImage);

	// set up event handlers for the Image object
	oImage.onload = ImagePreloader.prototype.onload;
	oImage.onerror = ImagePreloader.prototype.onerror;
	oImage.onabort = ImagePreloader.prototype.onabort;

	// assign pointer back to this.
	oImage.oImagePreloader = this;
	oImage.bLoaded = false;

	// assign the .src property of the Image object
	oImage.src = image;
}

ImagePreloader.prototype.onComplete = function(){
	this.nProcessed++;

	if(this.nProcessed == this.nImages){
		this.callback(this.aImages, this.nLoaded);
	}
}

ImagePreloader.prototype.onload = function(){
	this.bLoaded = true;
	this.oImagePreloader.nLoaded++;
	this.oImagePreloader.onComplete();
}

ImagePreloader.prototype.onerror = function(){
   this.bError = true;
   this.oImagePreloader.onComplete();
}

ImagePreloader.prototype.onabort = function(){
   this.bAbort = true;
   this.oImagePreloader.onComplete();

}