function updateTopButton() {
  if(getElt("top_button")) {
    var topButton = getElt("top_button");
    
    if(getWindowScrollTop() > 0) {
      setEltVisibility(topButton,'visible');
      setEltDisplay(topButton,'block');
      setEltPosition(topButton,'absolute');

      // aanpassing tbv schaalbaar maken //
      if (offsetRight==74) {
        setEltLeft(topButton,offsetRight+109);
      } else
      if (offsetRight!=0) {
        if (getWindowWidth() > 780)
          var difR = offsetRight + ((getWindowWidth() - 800) / 2);
        else difR = offsetRight-20;      
        setEltLeft(topButton,difR);
      }
      else {
      //  if (getWindowWidth() > 1006)      
          setEltLeft(topButton,getWindowWidth()-206);
      //  else setEltLeft(topButton,800);
      }
      var difT = (getWindowHeight() - offsetBottom) + (getWindowScrollTop()+4);
      setEltTop(topButton,difT);
    } else {
      setEltVisibility(topButton,'hidden');
      setEltDisplay(topButton,'none');
    }
  }
}

function updateTopButtonKidssite() {
  if(getElt("top_button")) {
    var topButton = getElt("top_button");
    
    if(getWindowScrollTop() > 0) {
      setEltVisibility(topButton,'visible');
      setEltDisplay(topButton,'block');
      setEltPosition(topButton,'absolute');

      setEltLeft(topButton,865);

      var difT = (getWindowHeight() - offsetBottom) + (getWindowScrollTop()+4);
      setEltTop(topButton,difT);
    } else {
      setEltVisibility(topButton,'hidden');
      setEltDisplay(topButton,'none');
    }
  }
}

function updateTopButtonKidssite_homepage() {
  if(getElt("top_button")) {
    var topButton = getElt("top_button");
    
    if(getWindowScrollTop() > 0) {
      setEltVisibility(topButton,'visible');
      setEltDisplay(topButton,'block');
      setEltPosition(topButton,'absolute');

      // aanpassing tbv schaalbaar maken //
      // if (getWindowWidth() > 800)
      //   var difR = offsetRight + ((getWindowWidth() - 800) / 2) ;
      // else difR = offsetRight;      
      // setEltLeft(topButton,difR);

    setEltLeft(topButton,870);

      var difT = (getWindowHeight() - offsetBottom) + (getWindowScrollTop()+4);
      setEltTop(topButton,difT);
    } else {
      setEltVisibility(topButton,'hidden');
      setEltDisplay(topButton,'none');
    }
  }
}

//functie voor imagemap in de header van Kidssite-werkstuk maken
var cur_activearea='';
function swapactivearea(new_activearea){
  if (cur_activearea!='')
  {
    eval(cur_activearea).className='map_onder';
  }
  cur_activearea=new_activearea;
  eval(new_activearea).className='map_boven'; 
}

function updateStaticButtons() {
  if(getElt("static_buttons")) {
    var static_buttons = getElt("static_buttons");
    
    setEltPosition(static_buttons,'absolute');
    var difT = getEltHeight(getElt("contents")) + 170;
    setEltTop(static_buttons,difT);
  }
}

function myTrimLeft(str) {
  var begin=0;
  while (begin<str.length &&
    (str.charAt(begin)==' ' ||
     str.charAt(begin)=='\t' ||
     str.charAt(begin)=='\r' ||
     str.charAt(begin)=='\n')) {
       begin++;
     }
  return str.substring(begin, str.length);
}

function myTrimRight(str) {
  var end=str.length;
  while (end>0 &&
    (str.charAt(end-1)==' ' ||
     str.charAt(end-1)=='\t' ||
     str.charAt(end-1)=='\r' ||
     str.charAt(end-1)=='\n')) {
       end--;
     }
  return str.substring(0, end);
}

function myTrim(str) {
  var result=""+str;
  result=myTrimRight(result);
  result=myTrimLeft(result);
  return result;
}

function checkForm(name) {
  obj = getForm(name);
  invalidFields = new Array();
  invalidNames = new Array();
  for (var i=0; i<requiredFields[name].length; i++) {
    var element=obj.elements[requiredFields[name][i]];
    if ((""+element.tagName).toUpperCase()=="SELECT") {
      if (!element.options[element.selectedIndex].value) {
        invalidFields[invalidFields.length] = element;
        invalidNames[invalidNames.length] = requiredLabels[name][i];
      }
    }
    else if (element.length) {
      optionChecked = false;
      for (var j=0; j<element.length; j++) {
        if (element[j].checked) {
          optionChecked = true;
        }
      }
      if (!optionChecked) {
        invalidFields[invalidFields.length] = element[0];
        invalidNames[invalidNames.length] = requiredLabels[name][i];
      }
    }
    else if (element.type != "hidden" &&
             (!element.value ||
              (element.name.indexOf("Tab.Src") != -1 ||
               element.name.indexOf("Email") != -1) &&
              ((""+element.value).indexOf("@")<0 ||
               (""+element.value).indexOf(".")<0))) {    
      invalidFields[invalidFields.length] = element;
      invalidNames[invalidNames.length] = requiredLabels[name][i];
    }
  }
  if (invalidFields.length > 0) {
    msg = formMessage;
    for (var i=0; i<invalidFields.length; i++) {
      if (document.all && invalidFields[i].type == "input") {
        invalidFields[i].style.borderColor = "#ff6600";
        invalidFields[i].style.backgroundColor = "#ffeecc";
      }
      msg += (i==0?'':'\n') + '- ' + invalidNames[i];
    }
    alert(msg);
    return false;
  }
  return (invalidFields.length == 0);
}

var locationUrl = '';
var locationType = '';
var locationWindow = '';

function setLocationUrl(baseUrl,obj,type) {
  locationType = type;
  if (locationType=='continent')
    locationUrl = baseUrl + obj.options[obj.selectedIndex].value+'?continent='+obj.options[obj.selectedIndex].value;
  else locationUrl = obj.options[obj.selectedIndex].value;
}

function openLocationUrl(){
  if (locationType=='land' && locationUrl.indexOf('_self')==-1)
    window.open(locationUrl);
  else document.location.href = locationUrl;
}

function submitForm(formName) {
  var form = document.forms[formName];
  form.submit();  
  return false;
}

function buttonOver(obj) {
  if (obj.previousClass = null)
    obj.previousClass = obj.className;
  obj.className = obj.className + " buttonOver"; 
}

function buttonOut(obj) {
  obj.className = obj.previousClass;
}

function jumpTo(id) {
  var elt = getElt(id);
  
  if (elt != null)
    elt.scrollIntoView();  
}