how to determine, using jquery, if the element is visible on the current page view. I'd like to add a comment functionality, which works like in facebook, where you only scroll to element if it's not currently visible. By visible, I mean that it is not in the current page view, but you can scroll to the element.
Live Demo
Basically you just check the position of the element to see if its within the windows viewport.
function checkIfInView(element){
var offset = element.offset().top - $(window).scrollTop();
if(offset > window.innerHeight){
// Not in view so scroll to it
$('html,body').animate({scrollTop: offset}, 1000);
return false;
}
return true;
}
Improving Loktar's answer, fixing the following:
Scroll up
Scroll to a display:none element (like hidden div's etc)
function scrollToView(element){
var offset = element.offset().top;
if(!element.is(":visible")) {
element.css({"visibility":"hidden"}).show();
var offset = element.offset().top;
element.css({"visibility":"", "display":""});
}
var visible_area_start = $(window).scrollTop();
var visible_area_end = visible_area_start + window.innerHeight;
if(offset < visible_area_start || offset > visible_area_end){
// Not in view so scroll to it
$('html,body').animate({scrollTop: offset - window.innerHeight/3}, 1000);
return false;
}
return true;
}
After trying all these solutions and many more besides, none of them satisfied my requirement for running old web portal software (10 years old) inside IE11 (in some compatibility mode). They all failed to correctly determine if the element was visible. However I found this solution. I hope it helps.
function scrollIntoViewIfOutOfView(el) {
var topOfPage = window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop;
var heightOfPage = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;
var elY = 0;
var elH = 0;
if (document.layers) { // NS4
elY = el.y;
elH = el.height;
}
else {
for(var p=el; p&&p.tagName!='BODY'; p=p.offsetParent){
elY += p.offsetTop;
}
elH = el.offsetHeight;
}
if ((topOfPage + heightOfPage) < (elY + elH)) {
el.scrollIntoView(false);
}
else if (elY < topOfPage) {
el.scrollIntoView(true);
}
}
I made a slightly more generic version of digitalPBK's answer that minimally scrolls an element contained within a div or some other container (including the body). You can pass DOM elements or selectors to the function, as long as the element is somehow contained within the parent.
function scrollToView(element, parent) {
element = $(element);
parent = $(parent);
var offset = element.offset().top + parent.scrollTop();
var height = element.innerHeight();
var offset_end = offset + height;
if (!element.is(":visible")) {
element.css({"visibility":"hidden"}).show();
var offset = element.offset().top;
element.css({"visibility":"", "display":""});
}
var visible_area_start = parent.scrollTop();
var visible_area_end = visible_area_start + parent.innerHeight();
if (offset-height < visible_area_start) {
parent.animate({scrollTop: offset-height}, 600);
return false;
} else if (offset_end > visible_area_end) {
parent.animate({scrollTop: parent.scrollTop()+ offset_end - visible_area_end }, 600);
return false;
}
return true;
}
You can take a look at his awesome link from the jQuery Cookbook:
Determining Whether an Element Is Within the Viewport
Test if Element is contained in the Viewport
jQuery(document).ready(function() {
var viewportWidth = jQuery(window).width(),
viewportHeight = jQuery(window).height(),
documentScrollTop = jQuery(document).scrollTop(),
documentScrollLeft = jQuery(document).scrollLeft(),
$myElement = jQuery('#myElement'),
elementOffset = $myElement.offset(),
elementHeight = $myElement.height(),
elementWidth = $myElement.width(),
minTop = documentScrollTop,
maxTop = documentScrollTop + viewportHeight,
minLeft = documentScrollLeft,
maxLeft = documentScrollLeft + viewportWidth;
if (
(elementOffset.top > minTop && elementOffset.top + elementHeight < maxTop) &&
(elementOffset.left > minLeft && elementOffset.left + elementWidth < maxLeft)
) {
alert('entire element is visible');
} else {
alert('entire element is not visible');
}
});
Test how much of the element is visible
jQuery(document).ready(function() {
var viewportWidth = jQuery(window).width(),
viewportHeight = jQuery(window).height(),
documentScrollTop = jQuery(document).scrollTop(),
documentScrollLeft = jQuery(document).scrollLeft(),
$myElement = jQuery('#myElement'),
verticalVisible, horizontalVisible,
elementOffset = $myElement.offset(),
elementHeight = $myElement.height(),
elementWidth = $myElement.width(),
minTop = documentScrollTop,
maxTop = documentScrollTop + viewportHeight,
minLeft = documentScrollLeft,
maxLeft = documentScrollLeft + viewportWidth;
function scrollToPosition(position) {
jQuery('html,body').animate({
scrollTop : position.top,
scrollLeft : position.left
}, 300);
}
if (
((elementOffset.top > minTop && elementOffset.top < maxTop) ||
(elementOffset.top + elementHeight > minTop && elementOffset.top +
elementHeight < maxTop))
&& ((elementOffset.left > minLeft && elementOffset.left < maxLeft) ||
(elementOffset.left + elementWidth > minLeft && elementOffset.left +
elementWidth < maxLeft)))
{
alert('some portion of the element is visible');
if (elementOffset.top >= minTop && elementOffset.top + elementHeight
<= maxTop) {
verticalVisible = elementHeight;
} else if (elementOffset.top < minTop) {
verticalVisible = elementHeight - (minTop - elementOffset.top);
} else {
verticalVisible = maxTop - elementOffset.top;
}
if (elementOffset.left >= minLeft && elementOffset.left + elementWidth
<= maxLeft) {
horizontalVisible = elementWidth;
} else if (elementOffset.left < minLeft) {
horizontalVisible = elementWidth - (minLeft - elementOffset.left);
} else {
horizontalVisible = maxLeft - elementOffset.left;
}
var percentVerticalVisible = (verticalVisible / elementHeight) * 100;
var percentHorizontalVisible = (horizontalVisible / elementWidth) * 100;
if (percentVerticalVisible < 50 || percentHorizontalVisible < 50) {
alert('less than 50% of element visible; scrolling');
scrollToPosition(elementOffset);
} else {
alert('enough of the element is visible that there is no need to scroll');
}
} else {
// element is not visible; scroll to it
alert('element is not visible; scrolling');
scrollToPosition(elementOffset);
}
The following code helped me achieve the result
function scroll_to_element_if_not_inside_view(element){
if($(window).scrollTop() > element.offset().top){
$('html, body').animate( { scrollTop: element.offset().top }, {duration: 400 } );
}
}
Here is the solution I came up with, working both up and down and using only Vanilla Javascript, no jQuery.
function scrollToIfNotVisible(element) {
const rect = element.getBoundingClientRect();
// Eventually an offset corresponding to the height of a fixed navbar for example.
const offset = 70;
let scroll = false;
if (rect.top < offset) {
scroll = true;
}
if (rect.top > window.innerHeight) {
scroll = true;
}
if (scroll) {
window.scrollTo({
top: (window.scrollY + rect.top) - offset,
behavior: 'smooth'
})
}
}
There is a jQuery plugin which allows us to quickly check if a whole element (or also only part of it) is within the browsers visual viewport regardless of the window scroll position. You need to download it from its GitHub repository:
Suppose to have the following HTML and you want to alert when footer is visible:
<section id="container">
<aside id="sidebar">
<p>
Scroll up and down to alert the footer visibility by color:
</p>
<ul>
<li><span class="blue">Blue</span> = footer <u>not visible</u>;</li>
<li><span class="yellow">Yellow</span> = footer <u>visible</u>;</li>
</ul>
<span id="alert"></span>
</aside>
<section id="main_content"></section>
</section>
<footer id="page_footer"></footer>
So, add the plugin before the close of body tag:
<script type="text/javascript" src="js/jquery-1.12.0.min.js"></script>
<script type="text/javascript" src="js/jquery_visible/examples/js/jq.visible.js"></script>
After that you can use it in a simple way like this:
<script type="text/javascript">
jQuery( document ).ready(function ( $ ) {
if ($("footer#page_footer").visible(true, false, "both")) {
$("#main_content").css({"background-color":"#ffeb3b"});
$("span#alert").html("Footer visible");
} else {
$("#main_content").css({"background-color":"#4aafba"});
$("span#alert").html("Footer not visible");
}
$(window).scroll(function() {
if ($("footer#page_footer").visible(true, false, "both")) {
$("#main_content").css({"background-color":"#ffeb3b"});
$("span#alert").html("Footer visible");
} else {
$("#main_content").css({"background-color":"#4aafba"});
$("span#alert").html("Footer not visible");
}
});
});
</script>
Here a demo
No-JQuery version.
The particular case here is where the scroll container is the body (TBODY, table.body) of a TABLE (scrolling independently of THEAD). But it could be adapted to any situation, some simpler.
const row = table.body.children[ ... ];
...
const bottomOfRow = row.offsetHeight + row.offsetTop ;
// if the bottom of the row is in the viewport...
if( bottomOfRow - table.body.scrollTop < table.body.clientHeight ){
// ... if the top of the row is in the viewport
if( row.offsetTop - table.body.scrollTop > 0 ){
console.log( 'row is entirely visible' );
}
else if( row.offsetTop - table.body.scrollTop + row.offsetHeight > 0 ){
console.log( 'row is partly visible at top')
row.scrollIntoView();
}
else {
console.log( 'top of row out of view above viewport')
row.scrollIntoView();
}
}
else if( row.offsetTop - table.body.scrollTop < table.body.clientHeight ){
console.log( 'row is partly visible at bottom')
row.scrollIntoView();
}
else {
console.log( 'row is out of view beneath viewport')
row.scrollIntoView();
}
I think this is the complete answer. An elevator must be able to go both up and down ;)
function ensureVisible(elementId, top = 0 /* set to "top-nav" Height (if you have)*/) {
let elem = $('#elementId');
if (elem) {
let offset = elem.offset().top - $(window).scrollTop();
if (offset > window.innerHeight) { // Not in view
$('html,body').animate({ scrollTop: offset + top }, 1000);
} else if (offset < top) { // Should go to top
$('html,body').animate({ scrollTop: $(window).scrollTop() - (top - offset) }, 1000);
}
}
}
Related
I have a simple function which detects if an element is in the viewport or that it is visible. If that element is visible, on every scroll I move that element down with .css() and change the top property to achieve some parallax effect. This element on which I check is in the viewport and when it moves it is repeated X times on the page. Everything works but only on the first element has this problem, all other elements inherit top position from the first.
Demo: http://codepen.io/riogrande/pen/RRVVwq (scroll down for effect).
EDIT: Some who answered had the wrong idea what I want, so I want the title (element) to move on scroll but only when its in viewport(visible). So when the first element with same class is visible its moving with scroll, then when you scroll below it its not visible anymore it should not move but the other one which is visible should be moving etc etc.
Jquery:
(function($) {
'use strict';
$.prototype.isVisible = function() {
var rect = this[0].getBoundingClientRect();
return (
(rect.height > 0 || rect.width > 0) &&
rect.bottom >= 0 &&
rect.right >= 0 &&
rect.top <= (window.innerHeight || document.documentElement.clientHeight) &&
rect.left <= (window.innerWidth || document.documentElement.clientWidth)
);
};
function doCheck() {
var elementToDetect = $('.text');
var scrolled = $(window).scrollTop();
if (elementToDetect.isVisible()) {
elementToDetect.css('top', (-100 + (scrolled * 0.2)) + 'px');
}
}
$(document).ready(function() {
doCheck();
});
$(window).scroll(function() {
doCheck();
});
})(jQuery);
jQuery applies operations like css() on each element matching the selector.
So if you iterate the jQuery object, you get this:
function doCheck() {
var elementToDetect = $('.text');
var scrolled = $(window).scrollTop();
for (var index = 0; index < elementToDetect.length; index++) {
var element = $(elementToDetect[index]);
if (element.isVisible()) {
element.css('top', (-100 + (scrolled * 0.2)) + 'px');
}
}
}
Which still has a problem, in that all the text maintain the same top relative to their image.
Edit:
Actually, the way I understand what you're doing, you want to let them all move in the same way as you scroll, so each starts above the image when it comes into view. This is closer to what you need:
function doCheck() {
var elementToDetect = $('.text');
for (var index = 0; index < elementToDetect.length; index++) {
var text = elementToDetect[index];
var parent = text.parentElement;
var parentTop = parent.getBoundingClientRect().top;
var scrolled = (window.innerHeight - parentTop);
if (scrolled < 0) {
scrolled = 0;
}
if (parentTop < window.innerHeight) {
$(text).css('top', (-100 + (scrolled * 0.2)) + 'px');
}
}
}
Basically, looking at scrollTop() is wrong, because you really want the position of the parent div to determine the placement of your text.
Here you need to check for each .text on the scroll:
function doCheck() {
var elementToDetect = $('.text');
var scrolled = $(window).scrollTop();
elementToDetect.each(function(i, txtEl) {
if (txtEl.isVisible()) {
txtEl.css('top', (-100 + (scrolled * 0.2)) + 'px');
}
});
}
And most likely you want to have a debouce there in the window.scroll:
var timer;
$(window).scroll(function() {
if(timer){ clearTimeout(timer); }
timer = setTimeout(function(){
doCheck();
}, 900);
});
$('.text') returns an array of elements. You need to apply the css transform to each item rather than the array of items. The below code may require an update to get the output you would like but I think it should get you going.
function doCheck() {
var scrolled = $(window).scrollTop();
$('.text').each(function() {
if($(this).isVisible()) {
$(this).css('top', (-100 + (scrolled * 0.2)) + 'px');
}
})
}
I'm trying to achieve what is outlined in this Stack Overflow question, without jQuery dependency: stackoverflow.com/questions/18358816/sticky-sidebar-stick-to-bottom-when-scrolling-down-top-when-scrolling-up
But I didn't want to hijack that question.
Basically, I want the content in the sidebar to be independently scrollable but fixed when the viewport reaches either end of the sidebars contents on scroll.
My main stumbling block appears to not being able to calculate the elementTop variable when the sidebar is absolutely positioned and between the top and bottom of the container which I have set to be full height.
Full code below:
var StickySidebar = function(eventie) {
var container, containerTop, containerHeight, // container
element, elementTop, elementHeight, elStyle, // element
viewportTop = -1, viewportHeight, documentTop, // viewport
lastViewportTop, scrollingDown, top = false , bottom = false,// sticky vars
scroll = window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.msRequestAnimationFrame ||
window.oRequestAnimationFrame ||
function(callback){ window.setTimeout(callback, 1000/60); },
options = {
container : document.querySelector('.sidebar-container'),
element : document.querySelector('.sidebar'),
sidebarClass : 'sidebar',
bottomOffset : -15,
topOffset: 90,
},
_updateValue = function() {
viewportHeight = window.innerHeight;
},
_offset = function(obj) {
var ol = ot = 0;
if (obj.offsetParent) {
do {
ol += obj.offsetLeft;
ot += obj.offsetTop;
} while (obj = obj.offsetParent);
}
return {
left: ol,
top: ot
};
},
init = function(){
if(options.element !== null) {
container = options.container;
containerTop = offset(container).top;
containerHeight = container.clientHeight;
element = options.element;
elementTop = offset(element).top;
elementHeight = options.element.clientHeight;
lastViewportTop = window.scrollY;
viewportHeight = window.innerHeight;
eventie.bind(document, "scroll", _loop);
eventie.bind(window, "resize", _updateValue);
}
},
_loop = function() {
if (viewportTop == window.pageYOffset) {
scroll(_loop);
return false;
} else viewportTop = window.pageYOffset;
_updateValue();
var viewportBottom, elementTooBig, topOffset;
elementTop = offset(element).top;
elementHeight = element.clientHeight;
containerHeight = container.clientHeight;
scrollingDown = viewportTop > lastViewportTop;
elementTooBig = elementHeight > viewportHeight;
console.log("elementTop : " + elementTop);
console.log("viewportTop : " + viewportTop);
if (scrollingDown) {
if (viewportTop + viewportHeight >= elementTop + elementHeight) {
element.setAttribute('style','position:fixed; bottom:30px;');
} else {
element.setAttribute('style','position:absolute; top:'+ elementTop +'px;'); // issue 1
}
if (viewportTop + viewportHeight > containerTop + containerHeight) {
element.setAttribute('style','position:absolute; bottom:0;');
}
} else {
if (viewportTop < containerTop - 60) {
element.removeAttribute('style');
return;
}
if (viewportTop <= elementTop) {
element.setAttribute('style','position:fixed; top:90px;');
} else {
element.setAttribute('style','position:absolute; top:'+ elementTop +'px;');
elementTop = viewportTop + elementTop;
}
}
lastViewportTop = viewportTop;
};
return {
init: init
};
}(eventie);
I've been trying to tackle this issue for a few weeks now, and it has been driving me insane. Any help would be greatly appreciated.
If you're just trying to achieve the desired result not necessarily creating that yourself - well, there are many JavaScript libraries that provide that.
For example, Stickyfill is actually a polyfill for position: sticky which is natively supported only in Firefox 41+ and Safari 8+. Here is the demo with all kinds of stickiness you can imagine :)
P.S. At first glance you might notice something about jQuery there, but it's pure JavaScript and just adds a jQuery extension.
I have image I am scrolling within a div.
It make sure the image is visible I am using
var isVisible = (
threshold.top >= -39 &&
threshold.bottom <= (window.innerHeight || document.documentElement.clientHeight)
);
What I am trying to do now is make sure that once the element is visible it is able to completely finish scrolling before going out of the view port.
I am thinking I can do this by effecting the speed value based on the the distance of the element from the top on the window. But I am having a very hard time doing this.
I am using .getBoundingClientRect() to get the distance the element is from the top of the viewport:
var threshold = document.getElementById('page-feature').getBoundingClientRect();
var thresholdY = threshold.top;
Below is my code so far:
function scrollImageInViewport() {
var threshold = document.getElementById('page-feature').getBoundingClientRect();
var thresholdY = threshold.top;
var isVisible = (
threshold.top >= -39 &&
threshold.bottom <= (window.innerHeight || document.documentElement.clientHeight)
);
if (isVisible && window.innerWidth > 550) {
scrollDir(thresholdY);
}
}
function scrollUp(thresholdY) {
if (thresholdCounter < maxScrollNegative) {
return;
} else {
pageScroll.setAttribute('style', '-webkit-transform:translate3d(0,' + (--thresholdCounter *speed) + 'px,0); -ms-transform:translate3d(0,' + (--thresholdCounter *speed) + 'px,0); transform:translate3d(0,' + (--thresholdCounter *speed) + 'px,0);');
}
};
function scrollDown(thresholdY) {
if (thresholdCounter > maxScrollPositive) {
return;
} else {
pageScroll.setAttribute('style', '-webkit-transform:translate3d(0,' + (++thresholdCounter *speed) + 'px,0); -ms-transform:translate3d(0,' + (++thresholdCounter *speed) + 'px,0); transform:translate3d(0,' + (++thresholdCounter *speed) + 'px,0);');
}
};
function scrollToTop(){
initScroll();
pageScroll.setAttribute('style', 'transform:translate3d(0,0,0);');
thresholdCounter = 0;
};
function scrollDir(thresholdY) {
var scroll = window.scrollY;
if(scroll > position) {
distanceFromTop(thresholdY);
scrollUp(thresholdY);
} else if (scroll < position ){
scrollDown(thresholdY);
}
position = scroll;
};
function distanceFromTop(thresholdY) {
if (thresholdY > 0) {
`enter code here`//set speed as distance from top /px of not shown content
speed = (scrollImageHeight - scrollVisibleHeight) / thresholdY;
}
};
function initScroll(){
position = window.scrollY;
pageScroll = document.getElementById('page-scroll');
scrollImageHeight = pageScroll.offsetHeight; //total height of scroll image
pagePanel = document.getElementById("pagePanel");
pageStyle = window.getComputedStyle(pagePanel,"");
size = pageStyle.getPropertyValue("height");
scrollVisibleHeight = parseInt(size, 10);//visible height of scroll image
scrollImageEnd = scrollImageHeight - scrollVisibleHeight;
maxScrollNegative = -scrollImageEnd / speed;
}
var speed;
var thresholdCounter = 0;
var maxScrollPositive = 0;
var position,
pageScroll,
scrollImageHeight,
pagePanel,
pageStyle,
size,
scrollVisibleHeight,
scrollImageEnd,
maxScrollNegative;
window.addEventListener('resize', scrollToTop);
document.addEventListener('scroll', scrollImageInViewport);
window.addEventListener('load', initScroll);
This is what I ended up with:
var featurePage = document.getElementById('page-feature')
var pageScroll = document.getElementById('page-scroll');
var startP, // where animation needs to begin
endP, // where animation needs to end
diff; // visible element size
function getElementOffset(){ //init
var de = document.documentElement;
var box = featurePage.getBoundingClientRect();
var top = box.top + window.pageYOffset - de.clientTop;
var bottom = box.bottom + window.pageYOffset - de.clientTop;
var winHight = window.innerHeight;
diff = bottom - top;
var elPadding = (winHight - diff);
startP = top - elPadding;
endP = bottom - elPadding;
scrollImage()
}
function scrollImage(){
var scrollImageHeight = pageScroll.offsetHeight;
var scrollPos = (window.pageYOffset !== undefined) ? window.pageYOffset : (document.documentElement || document.body.parentNode || document.body).scrollTop;
var s1 = scrollPos - startP;
var realPos = -s1/diff;
var lengthLeft = scrollImageHeight - (diff)
if ( realPos < 0.09 && realPos > -1){
pageScroll.setAttribute('style', '-webkit-transform:translate3d(0,' + (realPos * lengthLeft) + 'px,0); -ms-transform:translate3d(0,' + (realPos *lengthLeft) + 'px,0); transform:translate3d(0,' + (realPos *lengthLeft) + 'px,0);');
}
}
window.addEventListener('resize', getElementOffset);
document.addEventListener('scroll', getElementOffset);
I'm trying to get this div to stop at the bottom but for some reason once it reaches the bottom it starts jumping around.
Any ideas? It seems like even when bottom_offset < 181 it still keeps changing the css top property.
<script>
jQuery(document).ready(function() {
var el = jQuery('#contactBox');
top_offset = jQuery('#contactBox').offset().top - 60;
var box_height = el.height();
jQuery(window).scroll(function() {
var scroll_top = jQuery(window).scrollTop();
var bottom_offset = jQuery(document).height() - scroll_top - box_height;
var new_top_offset = jQuery(document).height() - box_height - 100;
if ((scroll_top > top_offset) && (bottom_offset > 180)) {
el.css('top', scroll_top - top_offset);
}
else if ((scroll_top > top_offset) && (bottom_offset < 181)) {
el.css('top', new_top_offset);
}
else {
el.css('top', '');
}
});
});
</script>
Not sure how the html and css is setup so I'm taking a guess.
If the div has a fixed position, you can remove the following code and it should stop at the bottom.
The new_top_offset made the div jump down when i scrolled near the bottom.
else if ((scroll_top > top_offset) && (bottom_offset < 181)) {
el.css('top', new_top_offset);
}
else {
el.css('top', '');
Well I went ahead and changed it so that it worked a bit differently. It would just calculate body height minus footer height and also do scroll top + height of the scrolling div, and then it only changes css if total_height < body_height.
Here's the code if anyone needs it in the future.
jQuery(document).ready(function() {
var el = jQuery('#contactBox');
top_offset = jQuery('#contactBox').offset().top - 60;
var box_height = el.height();
jQuery(window).scroll(function() {
var scroll_top = jQuery(window).scrollTop();
var total_height = scroll_top + box_height;
var body_height = jQuery('body').outerHeight() - 150;
if ((scroll_top > top_offset) && (total_height < body_height)) {
el.css('top', scroll_top - top_offset);
}
});
});
I have this very usefull little piece of javascript that centers mig div. By i would like to make it apply to 3 divs on the same site, without repeating the same piece of code 3 times.
Any ideas on how to do it?
Putting all 3 divs into 1 divs that takes care of it, is not and option.
<script type="text/javascript">
<!--
function getWindowHeight() {
var windowHeight = 0;
if (typeof(window.innerHeight) == 'number') {
windowHeight = window.innerHeight;
}
else {
if (document.documentElement && document.documentElement.clientHeight) {
windowHeight = document.documentElement.clientHeight;
}
else {
if (document.body && document.body.clientHeight) {
windowHeight = document.body.clientHeight;
}
}
}
return windowHeight;
}
function setContent() {
if (document.getElementById) {
var windowHeight = getWindowHeight();
if (windowHeight > 0) {
var contentElement = document.getElementById('outer');
var contentHeight = contentElement.offsetHeight;
if (windowHeight < 570) {
contentElement.style.position = 'relative';
contentElement.style.top = '30px';
}
else if (windowHeight - contentHeight > 0) {
contentElement.style.position = 'relative';
contentElement.style.top = ((windowHeight / 2) - (contentHeight / 2)) + 'px';
}
else {
contentElement.style.position = 'static';
}
}
}
}
window.onload = function() {
setContent();
}
window.onresize = function() {
setContent();
}
//-->
</script>
Regards Troels
You don't need to check if document.getElementById exists. It has been supported since the Roman Empire.
Pass the id or the actual element that has to be centered to your function. That removes the dependency on a fixed element (#outer) in your case and makes it more flexible. Also try to name your functions to be indicative of what they are actually doing. setContent is a very generic name and doesn't indicate the centering aspect anywhere.
function centerElementWithId(id) {
..
var contentElement = document.getElementById(id);
..
}
Then call it thrice,
centerElementWithId('outer')
centerElementWithId('secondDiv')
centerElementWithId('thirdDiv');