Scroll

Observe scroll progression and provides helpers for parallax, locking and sticky effects.

• Usage
• Events
• Scroll to
• Locker
• Parallax
• Sticky

Install

npm install @wide/scroll --save

Usage

Internally use uos library.

Initialize scroll observer:

import '@wide/scroll'

Events

3 events scroll, scroll.up or scroll.down will be triggerd on each scroll step:

import emitter from '@wide/emitter'

emitter.on('scroll', e => {
  e.value // progress in px
  e.progress // progress in %
  e.up // scrolling up
  e.down // scrolling down
})

emitter.on('scroll.up', e => {
  e.value // progress in px
  e.progress // progress in %
})

// or without emitter
document.onEvent('scroll.up', e => {})

Listen a specific range progression:

import { range } from '@wide/scroll'

range(300, 600, val => console.log(val)) // progress between 300px and 600px

Scroll to

Internally use jump.js library.

Listen jump link [data-scrollto] elements:

<div data-scrollto="#top">content</div>

Jump programmaticaly to an element:

import { scrollTo } from '@wide/scroll'

scrollTo('.something')

You can define global config applying to all links:

import { JUMP_CONFIG } from '@wide/scroll'

JUMP_CONFIG.offset = -20 // top offset for all jump

You can aslo define config locally by adding HTML attributes:

<button
  data-scrollto="#footer"
  data-scrollto.duration="1010"
  data-scrollto.offset="0"
  data-scrollto.a11y="false"
  data-scrollto.callback="scrollToCallback"
  data-scrollto.easing="scrollToEasing"
>
  Scroll to footer
</button>

window.scrollToCallback = () => {
  // Do some stuffs when scroll has been completed
}

window.scrollToEasing = () => {
  // My custom easing animation code
}

Note: Those parameters will override default (global) parameters.

Parameters

Name	Type	Description	Default value
duration	number	Pass the time the scrollto() takes, in milliseconds.	800
offset	number	Offset a scrollto(), only if to an element, by a number of pixels.	-80
a11y	boolean	If enabled, and scrolling to an element: add a tabindex to, and focus the element	true
callback	function	Pass a function that will be called after the scrollto() has been completed.	null
easing	function	Easing function used to transition the scrollto().	null

More informations on Jump.js documentation.

Locker

Internally use body-scroll-lock library.

Lock page scroll, usefull when using a modal:

import { lock } from '@wide/scroll/lib/locker'

lock(el) // pass an element to NOT lock, like the modal itself

And then unlock it:

import { unlock } from '@wide/scroll/lib/locker'

unlock()

These methods can be called through the event dispatcher:

import '@wide/scroll/lib/locker'
import { emit } from '@wide/emitter'

emit('scroll.lock', el)
emit('scroll.unlock')

Parallax

Internally use rellax library.

Add parallax effect to [data-parallax] elements:

import '@wide/scroll/lib/parallax'

<div data-parallax>content</div>

Or for an horizontal effect:

<div data-parallax.x>content</div>

The moving speed can be customized (from -10 to 10):

<div data-parallax="4">content</div>

Add programmaticaly parallax effect to an element (see rellax docs for all params):

import parallax from '@wide/scroll/lib/parallax'

const el = document.querySelector('.something')
parallax(el, { speed: .4 })

Sticky

Internally use stickybits library.

Add sticky behavior to [data-sticky] elements:

import '@wide/scroll/lib/sticky'

<div data-sticky>content</div>

The offset can be customized:

• [data-parallax.offset="20"] to set top offset (default 0)

Add programmaticaly sticky effect to element:

import sticky from '@wide/scroll/lib/sticky'

const el = document.querySelector('.something')
sticky(el, { offset: 20 })

Libraries

This package uses :

• uos
• jump.js
• body-scroll-lock
• rellax
• stickybits

Authors

• Aymeric Assier - github.com/myeti
• Julien Martins Da Costa - github.com/jdacosta

License

This project is licensed under the MIT License - see the licence file for details