I would like to create a div, that is situated beneath a block of content but that once the page has been scrolled enough to contact its top boundary, becomes fixed in place
This is how i did it with jquery. This was all cobbled together from various answers on stack overflow. This solution caches the selectors for faster performance and also solves the "jumping" issue when the sticky div becomes sticky.
Check it out on jsfiddle: http://jsfiddle.net/HQS8s/
CSS:
.stick {
position: fixed;
top: 0;
}
JS:
$(document).ready(function() {
// Cache selectors for faster performance.
var $window = $(window),
$mainMenuBar = $('#mainMenuBar'),
$mainMenuBarAnchor = $('#mainMenuBarAnchor');
// Run this on scroll events.
$window.scroll(function() {
var window_top = $window.scrollTop();
var div_top = $mainMenuBarAnchor.offset().top;
if (window_top > div_top) {
// Make the div sticky.
$mainMenuBar.addClass('stick');
$mainMenuBarAnchor.height($mainMenuBar.height());
}
else {
// Unstick the div.
$mainMenuBar.removeClass('stick');
$mainMenuBarAnchor.height(0);
}
});
});
Here is an extended version to Josh Lee's answer. If you want the div to be on sidebar to the right, and float within a range (i.e., you need to specify top and bottom anchor positions). It also fixes a bug when you view this on mobile devices (you need to check left scroll position otherwise the div will move off screen).
function moveScroller() {
var move = function() {
var st = $(window).scrollTop();
var sl = $(window).scrollLeft();
var ot = $("#scroller-anchor-top").offset().top;
var ol = $("#scroller-anchor-top").offset().left;
var bt = $("#scroller-anchor-bottom").offset().top;
var s = $("#scroller");
if(st > ot) {
if (st < bt - 280) //280px is the approx. height for the sticky div
{
s.css({
position: "fixed",
top: "0px",
left: ol-sl
});
}
else
{
s.css({
position: "fixed",
top: bt-st-280,
left: ol-sl
});
}
} else {
s.css({
position: "relative",
top: "",
left: ""
});
}
};
$(window).scroll(move);
move();
}
I used some of the work above to create this tech. I improved it a bit and thought I would share my work. Hope this helps.
jsfiddle Code
function scrollErrorMessageToTop() {
var flash_error = jQuery('#flash_error');
var flash_position = flash_error.position();
function lockErrorMessageToTop() {
var place_holder = jQuery("#place_holder");
if (jQuery(this).scrollTop() > flash_position.top && flash_error.attr("position") != "fixed") {
flash_error.css({
'position': 'fixed',
'top': "0px",
"width": flash_error.width(),
"z-index": "1"
});
place_holder.css("display", "");
} else {
flash_error.css('position', '');
place_holder.css("display", "none");
}
}
if (flash_error.length > 0) {
lockErrorMessageToTop();
jQuery("#flash_error").after(jQuery("<div id='place_holder'>"));
var place_holder = jQuery("#place_holder");
place_holder.css({
"height": flash_error.height(),
"display": "none"
});
jQuery(window).scroll(function(e) {
lockErrorMessageToTop();
});
}
}
scrollErrorMessageToTop();
This is a little bit more dynamic of a way to do the scroll. It does need some work and I will at some point turn this into a pluging but but this is what I came up with after hour of work.
You could use simply css, positioning your element as fixed:
.fixedElement {
background-color: #c0c0c0;
position:fixed;
top:0;
width:100%;
z-index:100;
}
Edit: You should have the element with position absolute, once the scroll offset has reached the element, it should be changed to fixed, and the top position should be set to zero.
You can detect the top scroll offset of the document with the scrollTop function:
$(window).scroll(function(e){
var $el = $('.fixedElement');
var isPositionFixed = ($el.css('position') == 'fixed');
if ($(this).scrollTop() > 200 && !isPositionFixed){
$el.css({'position': 'fixed', 'top': '0px'});
}
if ($(this).scrollTop() < 200 && isPositionFixed){
$el.css({'position': 'static', 'top': '0px'});
}
});
When the scroll offset reached 200, the element will stick to the top of the browser window, because is placed as fixed.
I have links setup in a div so it is a vertical list of letter and number links.
#links {
float:left;
font-size:9pt;
margin-left:0.5em;
margin-right:1em;
position:fixed;
text-align:center;
width:0.8em;
}
I then setup this handy jQuery function to save the loaded position and then change the position to fixed when scrolling beyond that position.
NOTE: this only works if the links are visible on page load!!
var listposition=false;
jQuery(function(){
try{
///// stick the list links to top of page when scrolling
listposition = jQuery('#links').css({'position': 'static', 'top': '0px'}).position();
console.log(listposition);
$(window).scroll(function(e){
$top = $(this).scrollTop();
$el = jQuery('#links');
//if(typeof(console)!='undefined'){
// console.log(listposition.top,$top);
//}
if ($top > listposition.top && $el.css('position') != 'fixed'){
$el.css({'position': 'fixed', 'top': '0px'});
}
else if ($top < listposition.top && $el.css('position') == 'fixed'){
$el.css({'position': 'static'});
}
});
} catch(e) {
alert('Please vendor admin@mydomain.com (Myvendor JavaScript Issue)');
}
});
In javascript you can do:
var element = document.getElementById("myid");
element.style.position = "fixed";
element.style.top = "0%";