Bootstrap 5 Lazy loading

#bootstrap #javascript #webdev #html

What are Bootstrap Lazy loading?

Bootstrap 5 Lazy Loading is a feature, that allows you to load images or videos only when they are visible on the screen.

Installation

Manual installation (zip package)

To take advantage of our Bootstrap images component and use them in your project, you first need to install the MDB 5 Free package

MDB CLI

Watch our Quick Start Tutorial to discover and use the full potential of MDB 5 and MDB CLI

NPM

Prerequisites

Before starting the project make sure to install Node LTS (12.x.x recommended).

Installation

To install MDB UI KIT in your project easily type the following command in the terminal:



npm i mdb-ui-kit

Importing JS modules

You can import the entire library or just individual modules:



import * as mdb from 'mdb-ui-kit'; // lib
import { Input } from 'mdb-ui-kit'; // module

Importing CSS file

To import MDB stylesheet please use the following syntax:



@import '~mdb-ui-kit/css/mdb.min.css';

Importing SCSS modules

You can also import individual SCSS modules. To do it properly, we recommend to copy them from the node_modules/mdb-ui-kit/src/scss location directly to your project and import in the same way as CSS files.

Webpack integration

You can significantly speed up the process of creating a new project based on Webpack using our Starter.

CDN

Installation via CDN is one of the easiest methods of integrating MDB UI KIT with your project. Just copy the latest compiled JS script tag and CSS link tag from cdnjs to the application.

Don't forget to add also Font Awesome and Roboto font if you need. Here's an example code:

CSS



<!-- Font Awesome -->
<link
  href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.1/css/all.min.css"
  rel="stylesheet"
/>
<!-- Google Fonts -->
<link
  href="https://fonts.googleapis.com/css?family=Roboto:300,400,500,700&display=swap"
  rel="stylesheet"
/>
<!-- MDB -->
<link
  href="https://cdnjs.cloudflare.com/ajax/libs/mdb-ui-kit/3.3.0/mdb.min.css"
  rel="stylesheet"
/>

JS



<!-- MDB -->
<script
  type="text/javascript"
  src="https://cdnjs.cloudflare.com/ajax/libs/mdb-ui-kit/3.3.0/mdb.min.js"
></script>

Customization

Basic example

Lazy Loading will automatically initialize after adding .lazy class to your img or video element. It is important to add data-mdb-lazy-src attribute - otherwise, Lazy Load will throw an error.

HTML



<div class="container lazy mt-5" style="height: 500px; overflow-y: scroll">
  <div class="row text-center" style="height: 800px">
    <p>Scroll down to see an image</p>

    <p><i class="far fa-arrow-alt-circle-down fa-3x my-4"></i></p>

    <img
      data-mdb-lazy-src="https://mdbootstrap.com/img/Photos/Slides/img%20(102).jpg"
      data-mdb-lazy-placeholder="https://place-hold.it/1321x583?text=Loading"
      alt="Example image"
      class="img-fluid lazy my-3"
      style="margin-top: 50% !important"
    />

    <video
      class="lazy img-fluid"
      data-mdb-lazy-src="https://mdbootstrap.com/img/video/Sail-Away.mp4"
      data-mdb-lazy-delay="1000"
      data-mdb-lazy-placeholder="https://place-hold.it/838x471?text=Loading"
      muted="muted"
      autoplay="autoplay"
    ></video>
  </div>
</div>

Offset

Use data-mdb-lazy-offset attribute to define an additional amount of pixels after which image or video will show.

HTML



<img

  data-mdb-lazy-src="https://mdbootstrap.com/img/Photos/Slides/img%20(102).jpg"

  data-mdb-lazy-offset="800"

  data-mdb-lazy-placeholder="https://place-hold.it/1321x583?text=Loading"

  alt="Example image"

  class="img-fluid lazy"

/>

You can see more customization examples on the 📄 Lazy loading documentation page

Crucial Resources

Here are the resources that we have prepared to help you work with this component:

Read 📄 Lazy loading documentation page <-- start here
In to get the most out of your project, you should also get acquainted with other Methods options related to Lazy loading. See the section below to find the list of them.
You can use Methods in 📥 Starter Bootstrap 5 templates
Templates are a part of 📦 Free UI Kit for Bootstrap 5
After finishing the project you can publish it with CLI in order to receive 💽 Free hosting (beta)