cwise89 / react-swipeable

React swipe event handler hook

React Swipeable

React swipe event handler hook

Github Pages Demo

Api

Use the hook and set your swipe(d) handlers.

const handlers = useSwipeable({
  onSwiped: (eventData) => console.log("User Swiped!", eventData),
  ...config,
});
return <div {...handlers}> You can swipe here </div>;

Spread handlers onto the element you wish to track swipes on.

Props / Config Options

Event handler props

{
  onSwiped,       // After any swipe   (SwipeEventData) => void
  onSwipedLeft,   // After LEFT swipe  (SwipeEventData) => void
  onSwipedRight,  // After RIGHT swipe (SwipeEventData) => void
  onSwipedUp,     // After UP swipe    (SwipeEventData) => void
  onSwipedDown,   // After DOWN swipe  (SwipeEventData) => void
  onSwiping,      // During swiping    (SwipeEventData) => void
  onTap,          // After a tap       ({ event }) => void
}

Configuration props and default values

{
  delta: 10,                            // min distance(px) before a swipe starts
  preventDefaultTouchmoveEvent: false,  // call e.preventDefault *See Details*
  trackTouch: true,                     // track touch input
  trackMouse: false,                    // track mouse input
  rotationAngle: 0,                     // set a rotation angle
}

Swipe Event Data

All Event Handlers are called with the below event data, SwipeEventData.

{
  event,          // source event
  initial,        // initial swipe [x,y]
  first,          // true for first event
  deltaX,         // x offset (current.x - initial.x)
  deltaY,         // y offset (current.y - initial.y)
  absX,           // absolute deltaX
  absY,           // absolute deltaY
  velocity,       // √(absX^2 + absY^2) / time - "absolute velocity" (speed)
  vxvy,           // [ deltaX/time, deltaY/time] - velocity per axis
  dir,            // direction of swipe (Left|Right|Up|Down)
}

None of the props/config options are required.

Hook details

• Hook use requires react >= 16.8.3
• The props contained in handlers are currently ref and onMouseDown
  • Please spread handlers as the props contained in it could change as react improves event listening capabilities

preventDefaultTouchmoveEvent details

This prop allows you to prevent the browser's touchmove event default action, mostly "scrolling".

Use this to stop scrolling in the browser while a user swipes.

• You can additionally try touch-action css property, see below

e.preventDefault() is only called when:

• preventDefaultTouchmoveEvent: true
• trackTouch: true
• the users current swipe has an associated onSwiping or onSwiped handler/prop

Example scenario:

If a user is swiping right with props { onSwipedRight: userSwipedRight, preventDefaultTouchmoveEvent: true } then e.preventDefault() will be called, but if the user was swiping left then e.preventDefault() would not be called.

Please experiment with the example app to test preventDefaultTouchmoveEvent.

passive listener

With v6 we've added the passive event listener option, by default, to internal uses of addEventListener. We set the passive option to false only when preventDefaultTouchmoveEvent is true.

When preventDefaultTouchmoveEvent is:

• true => el.addEventListener(event, cb, { passive: false })
• false => el.addEventListener(event, cb, { passive: true })

React's long running passive event issue.

We previously had issues with chrome lighthouse performance deducting points for not having passive option set.

Browser Support

The release of v6 react-swipeable we only support browsers that support options object for addEventListener, Browser compatibility. Which mainly means react-swipeable does not support ie11 by default, you need to polyfill options. For example using event-listener-with-options.

Version 6 Updates and migration

If upgrading from v5 or later please refer to the release notes and the v6 migration doc

v6 now only exports a hook, useSwipeable.

If would like something similar to the old <Swipeable> component you can recreate it from the hook. There are examples in the migration doc.

FAQs

How can I add a swipe listener to the document?

Example by @merrywhether #180

const { ref } = useSwipeable({
  ...
}) as { ref: RefCallback<Document> };

useEffect(() => {
  ref(document);
});

How to share ref from useSwipeable?

Example ref passthrough, more details #189:

const MyComponent = () => {
  const handlers = useSwipeable({ onSwiped: () => console.log('swiped') })

  // setup ref for your usage
  const myRef = React.useRef();

  const refPassthrough = (el) => {
    // call useSwipeable ref prop with el
    handlers.ref(el);

    // set myRef el so you can access it yourself
    myRef.current = el;
  }

  return (<div {...handlers} ref={refPassthrough} />
}

How to use touch-action to prevent scrolling?

Sometimes you don't want the body of your page to scroll along with the user manipulating or swiping an item.

You might try to prevent the event default action via preventDefaultTouchmoveEvent, which calls event.preventDefault(). But there may be a simpler, more effective solution, which has to do with a simple CSS property.

touch-action is a CSS property that sets how an element's region can be manipulated by a touchscreen user.

const handlers = useSwipeable({
  onSwiped: (eventData) => console.log("User Swiped!", evenData),
  ...config,
});
return <div {...handlers} style={{ touchAction: 'pan-y' }}> Swipe here </div>;

This explanation and example borrowed from use-gesture's wonderful docs.

Local Development

Initial install & setup, with node 10+ & yarn v1, run yarn.

Make changes/updates to the src/index.ts file.

Please add/update tests if PR adds/changes functionality.

Verify updates with the examples

Build, run, and test examples locally: yarn run start:examples

After the server starts you can then view the examples page with your changes at http://localhost:3000.

You can now make updates/changes to src/index.ts and webpack will rebuild, then reload the page so you can test your changes!

License

MIT