It’s important to note that the prefetching will only start after the browser has finished the initial load and becomes idle. It provides a set of values which can be used to configure how the image will display: Values. A simple lazy-load list component based Vue 2.x, which will be on-demand rendering the list based container element's viewport. This series is based on learnings from Vue Storefront performance optimization process. The reason why I’m still writing this article is, that I wanted a more lightweight solution. When building apps with a bundler, the JavaScript bundle can become quite large, and thus affect the page load time. It also makes sense to prefetch lazily loaded routes. Vue.js - The Progressive JavaScript Framework. Here are the most common ways to invoke dynamic loading of Vue component: Please note that the invocation of lazyComponent function will happen only when component is requested to render in a template. In most cases, you don’t need all the code from your Javascript bundle immediately when a user visits your website. The answer is easy — lazy loading and code splitting. dependency graph (click here to see how it looks like). If we import a JavaScript module in a standard way like this: It will be added as a node of a main.js in the dependency graph and bundled with it. As we know by making module dynamically imported we are cutting part of the dependency graph. .lazy. It’s called prefetching. Knowing how dynamic imports are working we know that product and category will end up in a separate bundles but what will happen with productGallery module that wasn’t dynamically imported? That’s probably the easiest way to gain some performance boost. It is important to understand exactly when a code-splitted component is fetched. // src/utils/lazy-load-component.js export default function lazyLoadComponent ({ componentFactory , loading , loadingData , }) { let resolveComponent ; return () => ({ // We return a promise to resolve a // component eventually. Hãy bắt đầu bằng việc tạo một component hiển thị một hình ảnh (đương nhiên là chưa có lazy load gì cả). So it turns out that all we need to do to lazily load any component is combining v-if directive and dynamic import statement like this: Lazy loading components can save a lot of time on initial download, but it comes with a price that the user has to pay later. To see how much of the JavaScript code is actually used in our website we can go to the devtools -> cmd+shift+p -> type coverage -> hit ‘record’. nuxt.config.js shows components: true for auto importing components. For example this code: The component will not be loaded until it is required in the DOM, which is as soon as the v-if value changes to true. In short we are creating a new VueI18n instance as we normally would. Ok, we know what lazy loading is and that it’s pretty useful. By using below techniques we were able to cut off size of our initial bundle by 70% and made it load in a blink of an eye. Now webpack will bundle the content of the dynamically imported module into a separate file. To prefetch any resource (usually we prefetch the code-splitted ones like off-screen components or routes) the only thing that you need to do is put it into a tag. Now when you click the button, you will lazy load the GreetComponent inside the parent component. On the other hand, lazy loading refers to an approach where all of the scripts are not loaded on the DOM as the application starts, instead, they are only loaded when requested, making the JavaScript bundle size very small at … You will learn how to split your Vue code with async routes along with recommended best practices for this process. I'm trying to determine the best approach for implementing lazy loading of this data - I only want to ask the server for it the first time I need it, cache it in the store, and use the cached value for as long as its valid. This is where dynamic imports can help us! That’s all! According to RAIL model guidelines every user input should generate a response in under 100ms.It is almost impossible to achieve such a low response time if we have to download resources before the application is able to respond. The bigger bundle, the longer it takes to download and parse for our users. We learned how to use lazy loading with Vue components. A small size Vue.js directive for lazy loading images using IntersectionObserver API - mazipan/vue-tiny-lazyload-img About; Contact; Write for Us! The good news is that it’s extremely easy and we can lazily load the entire Single File Component, with it’s CSS and HTML with the same syntax as … In this tutorial, we will show you some techniques of lazy load images using JavaScript. For those still not convinced if it is worth playing with lazy loading, here’s some raw numbers from the simple example we’ve been using. It turns out that the solution is extremely simple. When building apps with a bundler, the JavaScript bundle can become quite large, and thus affect the page load time. The easiest way to lazy load your content - 1.0.1 - a JavaScript package on npm - Libraries.io Now we should be able to see how much of the downloaded code was actually used. Laravel + Vue = Love . This article will outline how to lazy load (dynamically load) VueJS Single File Components. In the previous article, we’ve seen that we can drastically reduce bundle size by lazy loading every route in separation. If nothing happens when we interact with a website, we either perceive the application as slow or broken, and most of us leave the site. $ vue init webpack-simple infinite-scroll-vuejs Getting Initial User Data. Let’s see another example that will better illustrate this mechanism. It’s a graph that links all of our files based on imports. To understand while it’s crucial first we need to understand how Webpack is bundling all of our files. Take a look at below example: Assuming isModalVisible variable is set to false even though both statements will take the same effect from the user point of view the v-if directive will remove component from the DOM completely while v-show will just add display: none CSS property. Most of the tips in this series will focus on making our JS bundle smaller. The answer to this question is trivial and intuitive - everything that is not required on initial render. Single-file (.vue) components