/*
 * Adds a function to the window.onload event
 * Enables the usage of multiple functions on load
 */
function addLoadEvent(func){
 var oldOnload = window.onload;
 if(typeof window.onload != 'function'){
  window.onload = func;
 } else {
  window.onload = function(){
   if(oldOnload){
    oldOnload();
   }
   func();
  }
 }
}

/*
 * Navigation bar
 *
 * <activeNav> must de defined on every page
 */
function initNavbar(){
 var navUrls = new Array();       var navNames = new Array();  var navSizes = new Array();
 navUrls.push('/');               navNames.push('home');       navSizes.push(55);
 navUrls.push('/agenda.php');     navNames.push('agenda');     navSizes.push(71);
 navUrls.push('/kaart.php');      navNames.push('kaart');      navSizes.push(56);
 navUrls.push('/blog/');          navNames.push('blog');       navSizes.push(44);
 navUrls.push('/forum/');         navNames.push('forum');      navSizes.push(59);
 navUrls.push('/artikelen.php');  navNames.push('artikelen');  navSizes.push(81);
 navUrls.push('/boeken.php');     navNames.push('boeken');     navSizes.push(69);
 navUrls.push('/links.php');      navNames.push('links');      navSizes.push(49);
 navUrls.push('/overons.php');    navNames.push('overons');    navSizes.push(76);
 navUrls.push('/contact.php');    navNames.push('contact');    navSizes.push(69);

 var navImgDir = '/img/nav/';
 var navImgExt = '.png';
 var navbar = document.getElementById('navbar');
 for(var i=0; i < navUrls.length; i++){
  var url = navUrls[i];
  var name = navNames[i];
  var img = navImgDir + name + navImgExt;
  var size = navSizes[i];
  var a = document.createElement('a');
  a.href = url;
  var nav = document.createElement('div');
  nav.style.width = size + 'px';
  nav.style.backgroundImage = 'url(' + img + ')';
  if(name == activeNav){
   nav.className = 'active';
  }
  a.appendChild(nav);
  navbar.appendChild(a);
 }
} addLoadEvent(initNavbar);