FloatSidebar.js is a lightweight (2kb gzipped), zero-dependency JavaScript library that creates sticky, floating sidebars. It keeps the sidebar visible in the viewport by dynamically sticking it to the top or bottom based on scroll direction and sidebar height.

• When the sidebar is taller than the viewport, it scrolls with the content, sticking to the bottom when scrolling down and to the top when scrolling up.
• When the sidebar is shorter than the viewport: it stays fixed at the top during scrolling.

Example.mov

Demo

Install

npm install float-sidebar --save

or

yarn add float-sidebar

Usage

<divclass="wrapper"><divclass="content"><!-- Content --></div><divclass="sidebar"><divclass="sidebar__inner"><!-- Sidebar content --></div></div></div>

.wrapper {
display: flex;
/* Required when using infinite scroll */align-items: flex-start;
}
.sidebar {
/* Required */position: relative;
/* Required. The sidebar element should have a fixed width */width:220px;
}

importFloatSidebarfrom'float-sidebar';constsidebar=document.querySelector('.sidebar');constrelative=document.querySelector('.content');constfloatSidebar=FloatSidebar({
sidebar,
relative,topSpacing: 20,bottomSpacing: 20,});// ...floatSidebar.forceUpdate();// ...floatSidebar.destroy();

Options

Name	Type	Default	Description
sidebar	HTMLElement	Required	The sidebar element
relative	HTMLElement	Required	The sidebar relative element, e.g. the main content
viewport	HTMLElement	window	The viewport element
sidebarInner	HTMLElement	sidebar.firstElementChild	The sidebar inner element
topSpacing	number	0	The space from the top of the viewport. Used when the sidebar is in fixed state.
bottomSpacing	number	0	The space from the bottom of the viewport. Used when the sidebar is in fixed state.

Instance API

Method	Description
forceUpdate()	Recalculates the dimensions and updates the sidebar's position
destroy()	Cleans up DOM references and listeners

Similar libraries

• https://github.com/abouolia/sticky-sidebar

License

FloatSidebar.js is released under the MIT license.

Author Sergey Vinogradov