Imagine you generated a bunch of tickets for the Supabase Launch Week and you wanted to display them all on one page. It might take a while to load them all in one go, so a great solution to this would be to lazy load smaller subsets while the user scrolls, with a technique called infinite scrolling.
An infinite scroll allows you to scroll through your content endlessly while only loading the data you need as you need it. This improves performance while also creating a smooth and delightful user experience.
In this post, we'll go through the steps of how to create an infinite scroll using NextJs, Supabase, and Framer Motion.
What is infinite scroll?
Infinite scroll is a web design technique that automatically loads and displays new content as a user scrolls down a web page. This creates an endless scrolling experience that eliminates the need for pagination and provides a seamless and uninterrupted browsing experience.
Infinite scroll can enhance user experience and engagement by providing a fluid and intuitive browsing experience. It also allows for faster content delivery. By dynamically loading and displaying content as needed, infinite scroll can reduce the time and effort required to load pages and deliver content, improving overall performance and user satisfaction.
Next.js is a great choice for implementing infinite scroll in a web application. It provides server-side rendering and automatic code splitting, which can improve performance and optimize the loading of content as the user scrolls down the page. It also includes built-in support for dynamic imports and lazy loading, which can be useful for fetching and displaying content as needed.
Plus, incremental static regeneration (ISR) and pre-fetching of data can further improve performance by enabling the server to generate and cache pages in advance, and to pre-fetch data as the user scrolls down the page.
Now, onto the code!
Step 0. Load the first batch
First things first, let's install the dependencies we'll need.
_10npm install @supabase/supabase-js lodash framer-motion
Set up the supabase-js client and fetch the first 20 tickets through getServerSideProps so we don't start with an empty screen.
We'll assume our table in the db is called my_tickets_table.
_29import { useEffect, useState } from 'react'_29import { createClient } from '@supabase/supabase-js'_29_29const supabase = createClient('supabase-url', 'supabase-key')_29_29export default function TicketsPage({ tickets }) {_29 const [loadedTickets, setLoadedTickets] = useState(tickets)_29_29 return (_29 <div>_29 {loadedTickets.map((ticket, index) => (_29 {/* We'll get to this part later */}_29 ))}_29 </div>_29 )_29_29export const getServerSideProps: GetServerSideProps = async ({ req, res }) => {_29 const { data: tickets } = await supabase!_29 .from('my_tickets_table')_29 .select('*')_29 .order('createdAt', { ascending: false })_29 .limit(20)_29_29 return {_29 props: {_29 tickets,_29 },_29 }_29}
Step 1. Listen to the scroll
To detect if the user is scrolling we can listen to the window scroll event.
If you try to console.log() the event returned in the listener callback, you'll notice that it fires on every single pixel scrolled. We want to avoid triggering like crazy, so we'll use a lodash debounce function to limit how often we call this event to once every 200 milliseconds.
Here's what it looks like:
_14import { useEffect } from 'react'_14import { debounce } from 'lodash'_14_14const handleScroll = () => {_14 // Do stuff when scrolling_14}_14_14useEffect(() => {_14 const handleDebouncedScroll = debounce(() => handleScroll(), 200)_14 window.addEventListener('scroll', handleDebouncedScroll)_14 return () => {_14 window.removeEventListener('scroll', handleDebouncedScroll)_14 }_14}, [])
Step 2. Check if the container intersects the viewport
Next, we want to check if the bottom of the tickets container intersects with the bottom of the viewport. We can use the getBoundingClientRect method to get the position of the container and then compare it with the height of the viewport.
_24import { useRef, useState } from 'react'_24_24// ..._24_24const containerRef = useRef(null)_24const [offset, setOffset] = useState(1)_24const [isInView, setIsInView] = useState(false)_24_24const handleScroll = (container) => {_24 if (containerRef.current && typeof window !== 'undefined') {_24 const container = containerRef.current_24 const { bottom } = container.getBoundingClientRect()_24 const { innerHeight } = window_24 setIsInView((prev) => bottom <= innerHeight)_24 }_24}_24_24useEffect(() => {_24 if (isInView) {_24 loadMoreUsers(offset)_24 }_24}, [isInView])_24_24return <div ref={containerRef}>{/* List of loaded tickets */}</div>
Step 3. Load tickets based on the offset
Now we can load more tickets based on the current offset. We'll use the range method from the supabase-js library to easily work with the pagination logic.
_37export default function TicketsPage() {_37 const PAGE_COUNT = 20_37 const [offset, setOffset] = useState(1)_37 const [isLoading, setIsLoading] = useState(false)_37 const [isInView, setIsInView] = useState(false)_37_37 useEffect(() => {_37 if (isInView) {_37 loadMoreTickets(offset)_37 }_37 }, [isInView])_37_37 const loadMoreTickets = async (offset: number) => {_37 setIsLoading(true)_37 // Every time we fetch, we want to increase_37 // the offset to load fresh tickets_37 setOffset((prev) => prev + 1)_37 const { data: newTickets } = await fetchTickets(offset, PAGE_COUNT)_37 // Merge new tickets with all previously loaded_37 setLoadedTickets((prevTickets) => [...prevTickets, ...newTickets])_37 setIsLoading(false)_37 }_37_37 const fetchTickets = async (offset, limit) => {_37 const from = offset * PAGE_COUNT_37 const to = from + PAGE_COUNT - 1_37_37 const { data } = await supabase!_37 .from('my_tickets_table')_37 .select('*')_37 .range(from, to)_37 .order('createdAt', { ascending: false })_37_37_37 return data_37 }_37}
Step 4. Animate the tickets
Now that we have our tickets loaded, we want to add some animation to make them pop like dominos as they appear on the screen. For this, we're going to use the Framer Motion library.
We'll wrap each ticket in a motion component and add a transition effect to stagger their appearance on the screen:
_26import { motion } from 'framer-motion'_26_26// ..._26_26{_26 loadedTickets.map((ticket, index) => {_26 // each ticket will be delayed based on it's index_26 // but we need to subtract the delay from all the previously loaded tickets_26 const recalculatedDelay = i >= PAGE_COUNT * 2 ? (i - PAGE_COUNT * (offset - 1)) / 15 : i / 15_26_26 return (_26 <motion.div_26 key={ticket.id}_26 initial={{ opacity: 0, y: 20 }}_26 animate={{ opacity: 1, y: 0 }}_26 transition={{_26 duration: 0.4,_26 ease: [0.25, 0.25, 0, 1],_26 delay: recalculatedDelay,_26 }}_26 >_26 {/* Actual ticket component */}_26 </motion.div>_26 )_26 })_26}
With this code, each ticket will start with an opacity of 0 and a y position of 20. As it animates into view, it will fade in and move up to its final position. The delay for each ticket will be based on its index in the array, creating a nice staggered effect.
Step 5. Stop listening when finished
Once all the tickets have been loaded, we want to stop listening to the scroll event to avoid unnecessary requests. We can do this by setting a state variable called isLast to true whenever the length of the response will be less than PAGE_COUNT:
_10if (newTickets.length < PAGE_COUNT) {_10 setIsLast(true)_10}
We'll use this code to conditionally remove the event listener:
_10useEffect(() => {_10 const handleDebouncedScroll = debounce(() => !isLast && handleScroll(), 200)_10 window.addEventListener('scroll', handleScroll)_10 return () => {_10 window.removeEventListener('scroll', handleScroll)_10 }_10}, [])
Now, when the isLast state variable is true, the event listener will be removed and the component will stop listening to the scroll event.
Wrap up
That's it! We hope this post enabled you to build the next awesome infinite scroll.
Here's the complete code:
_98import { useEffect, useState, useRef } from 'react'_98import { createClient } from '@supabase/supabase-js'_98import { debounce } from 'lodash'_98import { motion } from 'framer-motion'_98_98const supabase = createClient('supabase-url', 'supabase-key')_98_98export default function TicketsPage({ tickets }) {_98 const PAGE_COUNT = 20_98 const containerRef = useRef(null)_98 const [loadedTickets, setLoadedTickets] = useState(tickets)_98 const [offset, setOffset] = useState(1)_98 const [isLoading, setIsLoading] = useState(false)_98 const [isInView, setIsInView] = useState(false)_98_98 const handleScroll = (container) => {_98 if (containerRef.current && typeof window !== 'undefined') {_98 const container = containerRef.current_98 const { bottom } = container.getBoundingClientRect()_98 const { innerHeight } = window_98 setIsInView((prev) => bottom <= innerHeight)_98 }_98 }_98_98 useEffect(() => {_98 const handleDebouncedScroll = debounce(() => !isLast && handleScroll(), 200)_98 window.addEventListener('scroll', handleScroll)_98 return () => {_98 window.removeEventListener('scroll', handleScroll)_98 }_98 }, [])_98_98 useEffect(() => {_98 if (isInView) {_98 loadMoreTickets(offset)_98 }_98 }, [isInView])_98_98 const loadMoreTickets = async (offset: number) => {_98 setIsLoading(true)_98 setOffset((prev) => prev + 1)_98 const { data: newTickets } = await fetchTickets(offset, PAGE_COUNT)_98 setLoadedTickets((prevTickets) => [...prevTickets, ...newTickets])_98 setIsLoading(false)_98 }_98_98 const fetchTickets = async (offset) => {_98 const from = offset * PAGE_COUNT_98 const to = from + PAGE_COUNT - 1_98_98 const { data } = await supabase!_98 .from('my_tickets_table')_98 .select('*')_98 .range(from, to)_98 .order('createdAt', { ascending: false })_98_98 return data_98 }_98_98 return (_98 <div ref={containerRef}>_98 {_98 loadedTickets.map((ticket, index) => {_98 const recalculatedDelay =_98 i >= PAGE_COUNT * 2 ? (i - PAGE_COUNT * (offset - 1)) / 15 : i / 15_98_98 return (_98 <motion.div_98 key={ticket.id}_98 initial={{ opacity: 0, y: 20 }}_98 animate={{ opacity: 1, y: 0 }}_98 transition={{_98 duration: 0.4,_98 ease: [0.25, 0.25, 0, 1],_98 delay: recalculatedDelay,_98 }}_98 >_98 {/* Actual ticket component */}_98 </motion.div>_98 )_98 })_98 }_98 </div>_98 )_98_98export const getServerSideProps: GetServerSideProps = async ({ req, res }) => {_98 const { data: tickets } = await supabase!_98 .from('my_tickets_table')_98 .select('*')_98 .order('createdAt', { ascending: false })_98 .limit(20)_98_98 return {_98 props: {_98 tickets,_98 },_98 }_98}
If you also want to feature in the endless tickets page and have a chance to win cool swag, you're invited to generate your unique ticket until April 16th.
See you at Launch Week! 👋
