Watch the fifth element open load
Then I saw it was directed by the same guy who made the science-fiction adventure Valerian and the City of a Thousand Planets,which I enjoyed, and Lucy, which was at least decent. I’d heard of it, but prior to Pat’s post had never known much about it.
#Watch the fifth element open load how to#
#Watch the fifth element open load code#
In conclusion, lazy loading images with the Intersection Observer API generally improves your page speed and performance, yet it makes your HTML code slightly larger. The browser makes subsequent requests for the remaining images as we scroll down. ? Bear in mind that Load time is affected by various factors, not just the image content. HTML file size: 6.6 KB ➡️ 3.4 KB larger (due to more markup).We’re going to check the difference between the page with lazy loaded images and regular images using Chrome DevTools (similar tools are available in Firefox and Safari if you prefer), specifically the Network and Audits panels. ??♀️ That said, they would most likely find your website faster and cost them less. Unless your images are exceptionally heavy and/or your user’s internet connection is too slow, users might not even notice the difference. addEventListener ( " DOMContentLoaded ", function () )() Run after the HTML document has finished loading document. Here I use a regular 1x1px grey PNG image. The placeholder image can be anything as long as it’s reasonably small. Add a data-src attribute with the image source value (ie.Replace the src attribute value with placeholder image.Next, we are doing three things to each element we want to lazy load: Use your own discretion to decide which images to load normally on your page!Īt this point, we already have regular images without lazy loading. immediately)-hence including them as our page’s “critical assets”-and lazy loading the rest as non-critical assets. The idea is to load the first x images as usual (ie. With the endless variations of device sizes, we don’t actually have “above the fold” the way we do with print. Each list item contains the cat’s name and image. Let’s start with basic HTML and CSS markup. When user scrolls/tabs toward each image, it requests the actual image and swaps the placeholder with the actual image.
![watch the fifth element open load watch the fifth element open load](http://image.tmdb.org/t/p/original/8a35VAcLRNk7YMCM0gcqnIQPGIq.jpg)
The Intersection Observer API watches the lazy-loaded images.During this process, the browser requests and loads images “above the fold” normally, and loads placeholder images for the remaining images. The browser calculates the space (element sizes, positions) and paints (renders) pixels to the screen.The browser parses the page’s HTML and CSS, combines them to build a render tree.In a nutshell, these are what happens when we load our gallery page:
![watch the fifth element open load watch the fifth element open load](https://is3-ssl.mzstatic.com/image/thumb/Video/v4/3c/ff/b7/3cffb7a5-3d23-5fe0-7707-7bf908258973/source/1200x630bf.jpg)
You can find further references at the end of this post. Note: Lazy loading also works with video, but here we are focusing on images. You can run and “remix” the code on Glitch below. There are plenty lazy loading libraries and plugins (which I include at the end of this post), but this is a fun way to understand how the Intersection Observer API works and how lazy loading works at the most basic level. We’re going to do this in plain HTML, CSS, and JS-no libraries or dependencies. In this post, we are building an image gallery that implements lazy loading. But thanks to the Intersection Observer API, which is already supported by most modern browsers, we can now implement lazy loading in under 20 lines of JavaScript! This used to be a messy effort, which involved adding/removing multiple event listeners and comparing sizes and positions. Image from the film “Spirited Away” (2001) It is potentially a waste of time, resources, and-referring to the former-users’ bandwidth (which equals money for users on mobile data). Not lazy loading your images is like ordering everything on the menu without knowing how much you’ll be able to eat. If your page contains, say, 20 images with total size of 5MB, but your user only scrolls to the third image, then it would not be necessary to request and load all 20 images immediately. “Lazy loading” is a technique that loads images or videos only when they are needed-that is, when they appear on screen. Improve your website’s speed and performance by “lazy loading” images with Intersection Observer API in just a few lines of vanilla JavaScript.