var postdata;	//globale variabele voor het mailformulier.
		var activePage = "Home";

		function checkBgon(plId)
		{
			plObj = document.getElementById(plId);
			if(plObj.style.visibility == '' || plObj.style.visibility == 'visible')
			{
				plObj.style.visibility = 'hidden'
			}
		}
		
		function checkBgoff(plId,inpObj)
		{
			plObj = document.getElementById(plId);
			
			if(inpObj.value == "")
			{
				if(plObj.style.visibility == 'hidden')
				{
					plObj.style.visibility = 'visible'
				}
			}
		}
		
		function showDot()
		{
			dotObj = document.getElementById('dot');
			if(dotObj) dotObj.style.visibility = 'visible'		
		}
		
		function hideDot()
		{
			dotObj = document.getElementById('dot');
			if(dotObj) dotObj.style.visibility = 'hidden'
		}
		
		function verstuurMail()
		{
			objNaam = document.getElementById('iNaam');
			objContact = document.getElementById('iContact');
			objVraag = document.getElementById('iVraag');
			
			if(objNaam.value == "" || objNaam.value == "uw naam...")
			{
				alert("U bent vergeten uw naam in te vullen.");
				objNaam.focus();
			}
			else if(objContact.value == "" || objContact.value == "uw contactgegevens...")
			{
				alert("U bent vergeten uw contactgegevens in te vullen.");
				objContact.focus();
			}
			else if(objVraag.value == "" || objVraag.value == "uw vraag/opmerking...")
			{
				alert("U bent vergeten uw vraag in te vullen.");
				objVraag.focus();
			}
			else
			{
				postdata = createQuery();
				loadPage('mail.php',2,'vakMiddleM','mail');
			}			
		}	
		
		function showPopup(foto,wi,he)
		{
			PosTop = (screen.availHeight - he) / 2;
			PosLeft = (screen.availWidth - wi) / 2;
			var image_big = window.open("popup.php?_url=" + foto,null,"left= " + PosLeft + ",top="+ PosTop +",height="+ he +",width="+ wi +",status=no,toolbar=no,menubar=no,location=no");
			image_big.focus();		
		}
		
		function init(pageId)
		{
			hideAll();
			activePage = pageId;
			pijlObj = document.getElementById('pijl' + activePage);
			if(pijlObj) pijlObj.style.visibility = 'visible';
		}
		
		function hideAll()
		{
			pijlObj = document.getElementById('pijlHome');
			if(pijlObj) pijlObj.style.visibility = 'hidden';
			pijlObj = document.getElementById('pijlBedrijf');
			if(pijlObj) pijlObj.style.visibility = 'hidden';
			pijlObj = document.getElementById('pijlAanbod');
			if(pijlObj) pijlObj.style.visibility = 'hidden';
			pijlObj = document.getElementById('pijlContact');
			if(pijlObj) pijlObj.style.visibility = 'hidden';
		}
		
		function displayThis(objId,wat)
		{
			obj = document.getElementById(objId);
			if(obj) obj.style.visibility = wat;
		}
		
		function mouseOver(pageId)
		{
			//if(pageId != activePage)
			//{
				pijlObj = document.getElementById('pijl' + pageId);
				if(pijlObj) pijlObj.style.visibility = 'visible';
			//}
		}
		
		function mouseOut(pageId)
		{
			//if(pageId != activePage)
			//{
				pijlObj = document.getElementById('pijl' + pageId);
				if(pijlObj) pijlObj.style.visibility = 'hidden';
			//}
		}
				
		function changeOn(id)
		{
			obj = document.getElementById(id);
			
			if(obj) obj.style.display = 'block';
		}
		
		function changeOff(id)
		{
			obj = document.getElementById(id);
			
			if(obj) obj.style.display = 'none';
		}
		
		function checkOff(objId,text)
		{
			obj = document.getElementById(objId);
			if(obj)
			{
				if(obj.value == text)
				{
					obj.value = "";
				}
			}
		}
		
		function checkOn(objId,text)
		{
			obj = document.getElementById(objId);
			if(obj)
			{
				if(obj.value == "")
				{
					obj.value = text;
				}
			}
		}
		
		function showContact()
		{
			obj = document.getElementById('contact_gegevens');
			if(obj) obj.style.visibility = 'visible';
		}
		
		function showPijlen(l,r)
		{
			obj = document.getElementById(l);
			if(obj) obj.style.visibility = 'visible';	
			obj = document.getElementById(r);
			if(obj) obj.style.visibility = 'visible';	
		}
		
		function hidePijlen(l,r)
		{
			obj = document.getElementById(l);
			if(obj) obj.style.visibility = 'hidden';	
			obj = document.getElementById(r);
			if(obj) obj.style.visibility = 'hidden';	
		}
			
		function hide(objId,textId,imgPijlId)
		{
			obj = document.getElementById(objId);
			if(obj) obj.style.visibility = 'hidden';			//Maak over plaatje onzichtbaar
			textObj = document.getElementById(textId);
			if(textObj) textObj.style.color = '#3E3E3E';	//Maak text label originele kleur
			imgPijlObj = document.getElementById(imgPijlId);
			if(imgPijlObj) imgPijlObj.style.visibility = 'hidden'; //maak pijl onzichtbaar
		}
		
		function show(objId,textId,imgPijlId)
		{		
			obj = document.getElementById(objId);
			if(obj) obj.style.visibility = 'visible';			//Maak over plaatje zichtbaar
			textObj = document.getElementById(textId);
			if(textObj) textObj.style.color = '#D200FF';	//Maak text label nieuwe kleur CF57FE
			imgPijlObj = document.getElementById(imgPijlId);
			if(imgPijlObj) imgPijlObj.style.visibility = 'visible'; //maak pijl zichtbaar
		}
		
		function hideK(objId)
		{
			obj = document.getElementById(objId);
			if(obj) obj.style.visibility = 'hidden';			//Maak over plaatje onzichtbaar
		}
		
		function showK(objId)
		{		
			obj = document.getElementById(objId);
			if(obj) obj.style.visibility = 'visible';			//Maak over plaatje zichtbaar
		}
		
		function hideG(objId)
		{
			obj = document.getElementById(objId);
			if(obj) obj.style.visibility = 'hidden';			//Maak over plaatje onzichtbaar
			textObj = document.getElementById('vak_gallery_cat');
			if(textObj) textObj.innerHTML = '';			//Maak text label zichtbaar
		}
		
		function showG(objId,textData)
		{	
			obj = document.getElementById(objId);
			if(obj) obj.style.visibility = 'visible';			//Maak over plaatje zichtbaar
			textObj = document.getElementById('vak_gallery_cat');
			if(textObj) 
			{
				textObj.innerHTML = textData;	//Maak text label onzichtbaar
			}
		}
		
		function displayText(strText)
		{
			textObj = document.getElementById('knopTekst');
			if(textObj) 
			{
				textObj.innerHTML = strText; //plaats de textstring in het object
			}
		}
		
		function changeFoto(urlFoto,urlImp)
		{
			//foto
			loadPage(urlFoto,1,'foto','impressie');
			//knopImpressie
			loadPage(urlImp,1,'knopImpressie','impressie');
		}
		
		function loadPage(url,chng,objId,pagina) {
			var req = false;
			
			var contentType = "application/x-www-form-urlencoded; charset=UTF-8";
		
			if (window.XMLHttpRequest) { // Mozilla, Safari,...
				req = new XMLHttpRequest();
				if (req.overrideMimeType) {
					req.overrideMimeType('text/xml');                
				}
			} else if (window.ActiveXObject) { // IE
				try {
					req = new ActiveXObject("Msxml2.XMLHTTP");
				} catch (e) {
					try {
						req = new ActiveXObject("Microsoft.XMLHTTP");
					} catch (e) {}
				}
			}
		
			if (!req) {
				alert('Giving up :( Cannot create an XMLHTTP instance');
				return false;
			}
			req.onreadystatechange = function() { showPage(req,url,objId,pagina); };
			if(chng == "1")
			{
				req.open('GET',  url , true);
				req.send(null);
			}
			else 
			{
				req.open('POST',  url , true);
				req.setRequestHeader("Content-Type", contentType);
				req.send(postdata);
			}
		}
		
		function showPage(req,url,objId,pagina) {
			if (req.readyState == 4) 
			{
				init(pagina);
				document.getElementById(objId).innerHTML = req.responseText;
			}
			else 
			{
				document.getElementById(objId).innerHTML = ' ';
			}
		}
		
		function changePage(paginaUrl,pagina)
		{
			loadPage(paginaUrl,1,'kaderTekst',pagina);
			if(pagina == "contact") loadPage('contactForm.php',1,'foto',pagina);
			else loadPage('foto.php',1,'foto',pagina);
		}
		
		function createQuery()
		{
			var Hform = document.getElementById('emailformulier');
		    var elements = Hform.elements;
		    var pairs = new Array();
		    for (var i = 0; i < elements.length; i++) 
			{
		       if ((name = elements[i].name) && (value = elements[i].value))
		            pairs.push(name + "=" + encodeURIComponent(value));
		    }
		
		    return pairs.join("&");
		}