@lancecummings/use-scroll-position
v1.1.45
Published
Use scroll position ReactJS hook done right
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use-scroll-position
use-scroll-position
is a React hook that returns the browser viewport X and Y scroll position. It is highly optimized and using the special technics to avoid unnecessary rerenders!
It uses the default react hooks rendering lifecycle, which allows you to fully control its behavior and prevent unnecessary renders.
Demo
Install
yarn add @n8tb1t/use-scroll-position
Usage
useScrollPosition(effect,deps, element, useWindow, wait)
| Arguments | Description |
| --------- | ----------- |
effect
| Effect callback.
deps
| For effects to fire on selected dependencies change.
element
| Get scroll position for a specified element by reference.
useWindow
| Use window.scroll
instead of document.body.getBoundingClientRect()
to detect scroll position.
wait
| The timeout
in ms. Good for performance.
The
useScrollPosition
returnsprevPos
andcurrPos
.
Examples
Log current scroll position
import { useScrollPosition } from '@n8tb1t/use-scroll-position'
useScrollPosition(({ prevPos, currPos }) => {
console.log(currPos.x)
console.log(currPos.y)
})
Change state based on scroll position - Inline CSS
import React, { useState } from 'react'
import { useScrollPosition } from '@n8tb1t/use-scroll-position'
const [headerStyle, setHeaderStyle] = useState({
transition: 'all 200ms ease-in'
})
useScrollPosition(
({ prevPos, currPos }) => {
const isVisible = currPos.y > prevPos.y
const shouldBeStyle = {
visibility: isVisible ? 'visible' : 'hidden',
transition: `all 200ms ${isVisible ? 'ease-in' : 'ease-out'}`,
transform: isVisible ? 'none' : 'translate(0, -100%)'
}
if (JSON.stringify(shouldBeStyle) === JSON.stringify(headerStyle)) return
setHeaderStyle(shouldBeStyle)
},
[headerStyle]
)
const Header = <header style={{ ...headerStyle }} />
Change state based on scroll position - Styled Components
import React, { useState } from 'react'
import { useScrollPosition } from '@n8tb1t/use-scroll-position'
const [hideOnScroll, setHideOnScroll] = useState(true)
useScrollPosition(({ prevPos, currPos }) => {
const isShow = currPos.y > prevPos.y
if (isShow !== hideOnScroll) setHideOnScroll(isShow)
}, [hideOnScroll])
Get scroll position for custom element
const [elementPosition, setElementPosition] = useState({ x: 20, y: 150 })
const elementRef = useRef()
// Element scroll position
useScrollPosition(
({ currPos }) => {
setElementPosition(currPos)
}, [], elementRef
)
Why to use
use-scroll-position
returns the scroll position of the browser window, using a modern, stable and performant implementation.
Most of the time scroll listeners do very expensive work, such as querying dom elements, reading height / width and so on.
use-scroll-position
solves this by using throttling
technic to avoid too many reflows (the browser to recalculate everything).