mach1/floating-ui

Popper is now Floating UI! For Popper v2, visit its dedicated branch. For help on migrating, check out the Migration Guide.

Floating UI is a tiny, low-level library for creating "floating" elements like tooltips, popovers, dropdowns, menus, and more.

The library provides two key functionalities:

1. Anchored positioning primitives

CSS is currently missing a feature called “anchored positioning” — the ability to anchor an element (like a tooltip) to another one (like a button) while simultaneously keeping it in view as best as possible by avoiding clipping and overflow.

Attempting to do fully dynamic anchored positioning with today’s plain CSS is not possible. Floating UI provides a JavaScript implementation of this feature.

2. User interaction primitives

When creating a popover, dropdown menu, select, or combobox component that follows WAI-ARIA authoring practices, the complexity increases dramatically. Focus traps, indexed navigation, and typeahead are difficult to get right.

This functionality is currently available for React DOM but will be made agnostic in the future.

Install

Choose the package that suits you.

Vanilla DOM positioning engine

Use with vanilla JavaScript or a non-React framework (view tutorial).

npm install @floating-ui/dom

React DOM positioning engine

Use with React DOM (view docs).

npm install @floating-ui/react-dom

React DOM interactions and positioning engine

Primitive hooks and components, in addition to the positioning engine, to use with React DOM (view docs).

npm install @floating-ui/react-dom-interactions

React Native positioning engine

Use with React Native (view docs).

npm install @floating-ui/react-native

Canvas or other platforms

Learn about creating a Platform.

npm install @floating-ui/core

Quick start

import {computePosition} from '@floating-ui/dom';

const referenceElement = document.querySelector('#button');
const floatingElement = document.querySelector('#tooltip');

function applyStyles({x = 0, y = 0, strategy = 'absolute'}) {
  Object.assign(floatingElement.style, {
    position: strategy,
    left: `${x}px`,
    top: `${y}px`,
  });
}

applyStyles();

computePosition(referenceElement, floatingElement, {
  placement: 'right',
}).then(applyStyles);

Visit the docs for detailed information.

Package entry points

Using webpack, Vite, or Parcel? Skip this section as modern bundlers handle this for you.

Floating UI uses process.env.NODE_ENV to determine whether your build is in development or production mode. This allows us to add console warnings and errors during development to help you but ensure they get stripped out in production to keep the bundle size small.

This causes an error in Rollup and low/no-build setups. To solve this, Floating UI exports browser-ready ES modules. Leverage the "browser" package export condition to use these modules.

Rollup example

The browser option in the nodeResolve() plugin will select browser versions of packages if available.

import {nodeResolve} from '@rollup/plugin-node-resolve';

export default {
  // ...
  plugins: [
    nodeResolve({
      browser: true,

      // Add this line for development config, omit for
      // production config
      exportConditions: ['development'],
    }),
  ],
};

Contributing

This project is a monorepo written in TypeScript using npm workspaces. The website is using Next.js SSG and Tailwind CSS for styling.

Fork and clone the repo
Install dependencies in root directory with npm install
Build initial package dist files with npm run build

Testing grounds

npm -w packages/dom run dev in the root will launch the @floating-ui/dom development visual tests at http://localhost:1234. The playground uses React to write each test route, bundled by Parcel.

Each route has screenshots taken of the page by Playwright to ensure all the functionalities work as expected; this is an easy, reliable and high-level way of testing the code.

Below the main container are UI controls to turn on certain state and options. Every single combination of state is tested visually via the snapshots to cover as much as possible.

Credits

The floating shapes in the banner image are made by the amazing artists @artstar3d, @killnicole and @liiiiiiii on Figma — check out their work!

License

MIT

mach1 / floating-ui