react-native-web/docs/guides/getting-started.md

Getting started

This guide will help you render components and applications with React Native for Web.

Your application may need to polyfill Promise, Object.assign, Array.from, and ResizeObserver as necessary for your desired browser support.

If you're not familiar with setting up a new React web project, please follow the recommendations in the React documentation.

Install

yarn add react react-dom react-native-web

Starter kits

create-react-app includes built-in support for aliasing react-native-web to react-native.

create-react-app my-app

Configuring a module bundler

If you have a custom setup, you may choose to configure your module bundler to alias the package to react-native.

For example, modify your webpack configuration as follows:

// webpack.config.js
module.exports = {
  // ...the rest of your config

  resolve: {
    alias: {
      'react-native$': 'react-native-web'
    }
  }
}

Now you can create your components and applications with the React Native API.

Configuring Babel

Babel supports module aliasing using babel-plugin-module-resolver

{
  "plugins": [
    ["module-resolver", {
      "alias": {
        "^react-native$": "react-native-web"
      }
    }]
  ]
}

Configuring Jest

Jest can be configured using the provided preset. This will map react-native to react-native-web and provide appropriate mocks:

{
  "preset": "react-native-web"
}

Please refer to the Jest documentation for more information.

Configuring Flow

Flow can be configured to understand the aliased module:

[options]
module.name_mapper='^react-native$' -> 'react-native-web'

You may also need to include a custom libdef (example) in your config.

Configuring Node.js

Node.js can alias react-native to react-native-web using module-alias. This is useful if you want to pre-render the app (e.g., server-side rendering or build-time rendering).

// Install the `module-alias` package as a dependency first
const moduleAlias = require("module-alias");
moduleAlias.addAliases({
  "react-native": require.resolve("react-native-web"),
});
moduleAlias();

Other notes

Safari flexbox performance

Safari prior to version 10.1 can suffer from extremely poor flexbox performance. The recommended way to work around this issue (as used on mobile.twitter.com) is to set display:block on Views in your element hierarchy that you know don't need flexbox layout.