⚠️ Deprecated ☠️

Now that React Hooks have been released in version 16.8, this package has been deprecated in favor of use-breakpoint. This package will continue to work, but you should upgrade to React >=16.8 and use use-breakpoint.

breakpoint-observer

A React Component for rendering based on breakpoints.

Usage

The main import BreakpointObserver listens to breakpoint changes and uses React Context to pass it to components below:

import BreakpointObserver from 'breakpoint-observer';
...

ReactDOM.render(
  <BreakpointObserver
    breakpoints={{ mobile: 0, tablet: 768, desktop: 1280 }}
    defaultBreakpoint="desktop"
  >
    <App />
  </BreakpointObserver>,
  document.body
);

React hooks

import { useBreakpoint } from 'breakpoint-observer';

...

const CurrentBreakpoint = () => {
  const { breakpoint, maxWidth, minWidth } = useBreakpoint();

  return <p>The current breakpoint is {breakpoint}!</p>}
};

HOC

import { withBreakpoint } from 'breakpoint-observer';

...

const CurrentBreakpoint = withBreakpoint(({ breakpoint, maxWidth, minWidth }) => (
  <p>The current breakpoint is {breakpoint}!</p>}
));

Context

import { Consumer } from 'breakpoint-observer';

...

const CurrentBreakpoint = () => (
  <BreakpointObserver.Consumer>
    {({ breakpoint, maxWidth, minWidth } ) => <p>The current breakpoint is {breakpoint}!</p>}
  </BreakpointObserver.Consumer>
);

Callback usage

Import BreakpointObserver as a React component and give it a callback function via the onChange prop. The function will receive the current breakpoint like the BreakpointObserver.Consumer.

import BreakpointObserver from 'breakpoint-observer';

const myCallback = ({ breakpoint, maxWidth, minWidth }) =>
    console.log(`The current breakpoint is ${breakpoint}!`);

...

ReactDOM.render(
  <BreakpointObserver
    breakpoints={{ mobile: 0, tablet: 768 }}
    onChange={myCallback}
    defaultBreakpoint={'tablet'}
  />,
  document.body
);

SSR

For server-side rendering a defaultBreakpoint prop is supported. This value is returned when there is no window to calculate actual breakpoints from.

Functionality

This component uses the window.matchMedia functionality to calculate the current breakpoint. For a list of breakpoints, we generate some css media queries in the form of (min-width: XXXpx) and (max-width: YYYpx) and then add listeners for the changes. <BreakpointObserver /> will then update its state when the breakpoint changes from one rule to another.

Developing

This project is built with Typescript. A Storybook is included for local previewing. The easiest way to get started is cloning the repo and starting the storybook server locally via npm start.