A library used to position poppers in web applications.
A popper is an element on the screen which “pops out” from the
natural flow of your application.
Common examples of poppers are tooltips, popovers and drop-downs.
Well, basically, no.
Popper.js is a positioning engine, its purpose is to
calculate the position of an element to make it possible to position it
near a given reference element.
The engine is completely modular and most of its features are
implemented as modifiers (similar to middlewares or
plugins).
The whole code base is written in ES2015 and its features are
automatically tested on real browsers thanks to SauceLabs and TravisCI.
Popper.js has zero dependencies. No jQuery, no LoDash, nothing.
It’s used by big companies like Twitter in Bootstrap v4, Microsoft in
WebClipper and Atlassian in
AtlasKit.
This is the engine, the library that computes and, optionally, applies the styles to the poppers.
Some of the key points are:
Visit our project page to see a lot of examples of what you can do with Popper.js!
Find the documentation here.
Since lots of users just need a simple way to integrate powerful
tooltips in their projects, we created
Tooltip.js.
It’s a small library that makes it easy to automatically create tooltips
using as engine Popper.js.
Its API is almost identical to the famous tooltip system of Bootstrap,
in this way it will be easy to integrate it in your projects.
The tooltips generated by Tooltip.js are accessible thanks to the
aria tags.
Find the documentation here.
Popper.js is available on the following package managers and CDNs:
| Source | |
|---|---|
| npm | npm install popper.js --save |
| yarn | yarn add popper.js |
| NuGet | PM> Install-Package popper.js |
| Bower | bower install popper.js --save |
| unpkg | https://unpkg.com/popper.js |
| cdnjs | https://cdnjs.com/libraries/popper.js |
Tooltip.js as well:
| Source | |
|---|---|
| npm | npm install tooltip.js --save |
| yarn | yarn add tooltip.js |
| Bower* | bower install tooltip.js=https://unpkg.com/tooltip.js --save |
| unpkg | https://unpkg.com/tooltip.js |
| cdnjs | https://cdnjs.com/libraries/popper.js |
*: Bower isn’t officially supported, it can be used to install
Tooltip.js only trough the unpkg.com CDN. This method has the limitation
of not being able to define a specific version of the library. Bower and
Popper.js suggests to use npm or Yarn for your projects.
For more info, read the
related issue.
Popper.js is currently shipped with 3 targets in mind: UMD, ESM and ESNext.
dist/, can be used with webpack
and babel-preset-env;Make sure to use the right one for your needs. If you want to import
it with a <script> tag, use UMD.
Given an existing popper DOM node, ask Popper.js to position it near its button
var reference = document.querySelector('.my-button');
var popper = document.querySelector('.my-popper');
var anotherPopper = new Popper(
reference,
popper,
{
// popper options here
}
);Popper.js supports two kinds of callbacks, the onCreate
callback is called after the popper has been initialized. The
onUpdate one is called on any subsequent update.
const reference = document.querySelector('.my-button');
const popper = document.querySelector('.my-popper');
new Popper(reference, popper, {
onCreate: (data) => {
// data is an object containing all the informations computed
// by Popper.js and used to style the popper and its arrow
// The complete description is available in Popper.js documentation
},
onUpdate: (data) => {
// same as `onCreate` but called on subsequent updates
}
});Popper.js is based on a “plugin-like” architecture, most of its
features are fully encapsulated “modifiers”.
A modifier is a function that is called each time Popper.js needs to
compute the position of the popper. For this reason, modifiers should be
very performant to avoid bottlenecks.
To learn how to create a modifier, read the modifiers documentation
Integrating 3rd party libraries in React or other libraries can be a
pain because they usually alter the DOM and drive the libraries
crazy.
Popper.js limits all its DOM modifications inside the
applyStyle modifier, you can simply disable it and manually
apply the popper coordinates using your library of choice.
For a comprehensive list of libraries that let you use Popper.js into existing frameworks, visit the MENTIONS page.
Alternatively, you may even override your own
applyStyles with your custom one and integrate Popper.js by
yourself!
function applyReactStyle(data) {
// export data in your framework and use its content to apply the style to your popper
};
const reference = document.querySelector('.my-button');
const popper = document.querySelector('.my-popper');
new Popper(reference, popper, {
modifiers: {
applyStyle: { enabled: false },
applyReactStyle: {
enabled: true,
fn: applyReactStyle,
order: 800,
},
},
});Since the API changed, we prepared some migration instructions to make it easy to upgrade to Popper.js v1.
https://github.com/FezVrasta/popper.js/issues/62
Feel free to comment inside the issue if you have any questions.
Popper.js is very performant. It usually takes 0.5ms to compute a
popper’s position (on an iMac with 3.5G GHz Intel Core i5).
This means that it will not cause any jank,
leading to a smooth user experience.
The aim of Popper.js is to provide a stable and powerful positioning engine ready to be used in 3rd party libraries.
Visit the MENTIONS page for an updated list of projects.
I want to thank some friends and projects for the work they did:
Code and documentation copyright 2016 Federico Zivolo. Code released under the MIT license. Docs released under Creative Commons.