Sticky-kit provides an easy way to attach elements to the page when the user scrolls such that the element is always visible. The source can be found on GitHub.
Just call stick_in_parent on the elements you want to be stuck inside of
their parent. Sticky elements “bottom out” so they never leave the container,
no more worrying if a sticky element will accidentally cover your footer.
$("#sidebar").stick_in_parent();
Have a lot of sticky columns, or different sticky portions of the page? Call
stick_in_parent on all the elements at once.
$(".sticky_column").stick_in_parent();
Not sure if your sidebar or your main content is taller? Doesn’t matter, just
call stick_in_parent on all columns. Sticky-kit will only stick items if they
don’t take up the entire height of their parent.
$("#sidebar, #main_column").stick_in_parent();
Sticky elements taller than the viewport can scroll independently up and down, meaning you don’t have to worry about your content being cut off should the sticky element be too tall or the user’s resolution too small.
$("#sidebar").stick_in_parent();
To install include jquery.sticky-kit.js after including jQuery.
Usage:
$("#sticky_item").stick_in_parent();
// or
$("#sticky_item").stick_in_parent(options);
You can pass a hash of options to configure how Sticky Kit works. The following options are accepted, each one is optional:
parent — The element will be the parent of the sticky item. The
dimensions of the parent control when the sticky element bottoms out. Defaults
to the closest parent of the sticky element. Can be a selector.inner_scrolling — Boolean to enable or disable the ability of the sticky
element to scroll independently of the scrollbar when it’s taller than the
viewport. Defaults to true for enabled.sticky_class — The name of the CSS class to apply to elements when they
have become stuck. Defaults to "is_stuck".offset_top — offsets the initial sticking position by of number of pixels,
can be either negative or positivespacer — either a selector to use for the spacer element, or false to
disable the spacer. The selector is passed to
closest, so you should nest the sticky
element within the spacer. Defaults to Stiky Kit creating its own spacer.bottoming — Boolean to control whether elements bottom out. Defaults to truerecalc_every — Integer specifying that a recalc should automatically
take place between that many ticks. A tick takes place on every scroll event.
Defaults to never calling recalc on a tick.Various events are triggered from a sticky element when its state changes. They are:
sticky_kit:stick — Triggered when element becomes stuck.sticky_kit:unstick — Triggered when element becomes unstuck. (Note: an
element is still considered stuck when it has bottomed out)sticky_kit:bottom — Triggered when element bottoms out.sticky_kit:unbottom — Triggered when element is no longer bottomed out.For example, if we want to log when an element sticks and unsticks we might do:
$("#sticky_item").stick_in_parent()
.on("sticky_kit:stick", function(e) {
console.log("has stuck!", e.target);
})
.on("sticky_kit:unstick", function(e) {
console.log("has unstuck!", e.target);
});
Sticky Kit listens to one event on document.body.
sticky_kit:recalc — trigger this event to cause all sticky elements to be
recalculated. More information below.Sticky Kit also listens to an event on the sticky elements:
sticky_kit:detach — remove sticky kit and restore element to original
positionIf you want to remove sticky kit from an element after applying it you can send
that element a sticky_kit:detach event.
For example:
$("#sticky_item").trigger("sticky_kit:detach");
StickyKit takes scrolling performance very seriously. It’s built from the ground up to let you have sticky elements without incurring scroll lag or jank.
Probably the biggest cause of scrolling lag is onscroll handlers that do too much
work, trigger page reflows, etc. StickyKit avoids this by having a very light
scroll handler that operates on cached values.
If you notice that your sticky element is acting strange, like it pops to the bottom of the page, or jumps around, then your cached value are most likely outdated. Luckily it’s easy to fix, read Recalculating Sticky Elements below.
Sticky Kit has two internal callbacks:
recalc — Updates the cached sizes of the elements it checkstick — Checks and updates if necessary the sticky state from the cached valuesA tick happens on every scroll event. It’s designed to be as fast as possible.
A recalc happens whenever the cached values need to be updated. It’s
(comparatively) slower, so you don’t want to run this on every scroll event. A
recalc can happen automatically in the following cases: Sticky kit is first
initialized, on the following tick after the height of the document changes.
You can also manually trigger a recalc by sending an event, see below.
If you're changing the markup of your page on the fly by removing, adding or resizing elements then you most likely need to tell Sticky Kit to recalculate the sticky elements to guarantee they're positioned correctly.
You can manually cause a recalculation to happen by triggering an event on
document.body:
$(document.body).trigger("sticky_kit:recalc");
Typically you only need to trigger a recalculation if you are changing the positions/sizes of elements above the sticky element, adjacent to it, or the sticky element itself.
Instead of manually calling sticky_kit:recalc you can use the recalc_every
option described above to periodically do a recalculation between ticks.
Setting it to 1 will cause a recalculation to happen on every scroll event,
preventing the state from ever being out of date.
$("#sticky_item").stick_in_parent({recalc_every: 1});
If you're familiar with HTML and CSS then you probably know there are a handful
of different ways to make columns. Sticky kit works automatically with floated
columns, inline-block columns, or absolutely positioned elements. (Non column
elements like toolbars work great as well, for example the toolbar on this
site.)
Sticky Kit works with all modern browsers, and IE7+.
Note: only floated columns work in IE7.
recalc_every, bottoming, and
spacer options. Fix bug where some events weren’t getting removed on
detach. Fixed bug where sticky class was not removed on detach (poziworld),
pull jQuery from window if it can’t be found on this (Connor Peet)touchmove events for mobile (Alfredo
Motta), support absolutely positioned element (Pierre Spring), border-box
element sets spacer correctly (jasonpolito), bug fix for bottomed state (Pierre
Spring)sticky_kit:detach, Bug fixes: remove
stray top attribute when unfixing, fix issue with top when inner scrolling,
handle variable width elements correctly, recalc is called on window resize