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API

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
onSwipeStart, // Start of swipe (SwipeEventData) => void *see details*
onSwiping, // During swiping (SwipeEventData) => void
onTap, // After a tap ({ event }) => void

// Pass through callbacks, event provided: ({ event }) => void
onTouchStartOrOnMouseDown, // Called for `touchstart` and `mousedown`
onTouchEndOrOnMouseUp, // Called for `touchend` and `mouseup`
}

Details

  • onSwipeStart - called only once per swipe at the start and before the first onSwiping callback
    • The first property of the SwipeEventData will be true

Configuration props and default values

{
delta: 10, // min distance(px) before a swipe starts. *See Notes*
preventScrollOnSwipe: false, // prevents scroll during swipe (*See Details*)
trackTouch: true, // track touch input
trackMouse: false, // track mouse input
rotationAngle: 0, // set a rotation angle
swipeDuration: Infinity, // allowable duration of a swipe (ms). *See Notes*
touchEventOptions: { passive: true }, // options for touch listeners (*See Details*)
}

delta

delta can be either a number or an object specifying different deltas for each direction, [left, right, up, down], direction values are optional and will default to 10;

{
delta: { up: 20, down: 20 } // up and down ">= 20", left and right default to ">= 10"
}

swipeDuration

A swipe lasting more than swipeDuration, in milliseconds, will not be considered a swipe.

  • It will also not trigger any callbacks and the swipe event will stop being tracked
  • Defaults to Infinity for backwards compatibility, a sensible duration could be something like 250
{
swipeDuration: 250 // only swipes under 250ms will trigger callbacks
}

touchEventOptions

Allows the user to set the options for the touch event listeners( currently only passive option ).

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 the first event of a tracked swipe
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 changes event listening capabilities

preventScrollOnSwipe details

This prop prevents scroll during swipe in most cases. Use this to stop scrolling in the browser while a user swipes.

Swipeable will call e.preventDefault() internally in an attempt to stop the browser's touchmove event default action (mostly scrolling).

NOTE: preventScrollOnSwipe option supersedes touchEventOptions.passive for the touchmove event listener

Example scenario:

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

e.preventDefault() is only called when:

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

Please experiment with the example app to test preventScrollOnSwipe.

passive listener details

Swipeable adds the passive event listener option, by default, to internal uses of touch addEventListener's. We set the passive option to false only when preventScrollOnSwipe is true and only to touchmove. Other listeners will retain passive: true.

When preventScrollOnSwipe is:

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

Here is more information on react's long running passive event issue.

We previously had issues with chrome lighthouse performance deducting points for not having passive option set so it is now on by default except in the case mentioned above.

If, however, you really need all of the listeners to be passive (for performance reasons or otherwise), you can prevent all scrolling on the swipeable container by using the touch-action css property instead, see below for an example.