React Native: Getting Started with Lottie and Expo
In this tutorial, we will be using Lottie with React Native. Lottie is an opensource library that renders Adobe Effects by providing easy to use animations just like static images. These animations are beautiful. Lottie is a mobile library developed by AirBnB. These animations are exported as JSON files using Bodymovin to render the natively on mobile and in web applications.
👍 for designers who spend their time contributing in LottieFiles.
I will be using Expo XDE for brevity and to get started quickly. Create a new project using it. I am going to call
rn-lottie-example but you can call whatever you want.
When the XDE completes running ReactNative Package Manager and builds up the project, you can go to
Device dropdown menu at the right and click on whichever simlulator you have installed depending on the operations system you are using. Windows users please make sure you have android studio and necessary files installed and MacOS users, please have XCode installed or upto date.
You can also view the application, by running it using Expo Client on your mobile device. Note that, depending on your internet connection, this can be slow and your mobile device and development mahcine must be on same wifi. Scan the QR code in
Share section, you are ready to go. Once, the app is rendered, you will be welcomed by the default screen:
Now open your favorite text editor/IDE because we are going to start writing code in next section.
Installing Lottie as a dependency in a project can a bit tricky but fortunately, Expo provides support for it. We do not have to install anything since we are using Expo. We directly import the dependency in our
Sine Lottie in Expo project is in Alpha mode, do not get worried by the word
Include a local state in our application called
animation. We will call this help in playing and restarting the animation itself. I am using this file for our animation from LottieFiles.com so you can download it. Of course, you are free to choose any other. Animations listed on the site are open source.
Later, we will using the
state.animation to source the animation file fetched directly in
Defining the animation
We will define two custom functions:
_loadAnimationAsync that perform the animation and load the animation from the internet using the
fetch API. We will also be pre-mounting our animation using
componentWillMount() method availble to us by core React. In this Life cycle method, when the state is set, it can be called before the initial render.
In general, it is used to prepare either the first render or update the state before the render. This is why we are using it. We need to update the state we defined.
fetch API to get the animation from its source. This does mean, that the animation is coming from internet so if you are testing on your mobile device, make sure you have access to internet.
This how our render function looks like:
We separatly define styling for the overall container and the animation. To load the animation, we will set its
transparent in order to remove any background color it has by default.
You can see the application working
This tutorial shows how you can get started with Lottie animation library using React Native and Expo. There are other ways to define animations and you can go in-depth as much as you want. This article is written for a beginner’s point of view.
For alternative to Lottie, you can check Facebook’s Keyframes that also uses Adobe After Effects to create one.