This is documentation for the next SDK version. For up-to-date documentation, see the latest version (SDK 52).

Set of common methods and types for Expo and related packages.

Installation

API

import * as Expo from 'expo';

expo/fetch API

expo/fetch provides a WinterCG-compliant Fetch API that works consistently across web and mobile environments, ensuring a standardized and cross-platform fetch experience within Expo applications.

import { fetch } from 'expo/fetch';

const resp = await fetch('https://httpbin.org/drip?numbytes=512&duration=2', {
  headers: { Accept: 'text/event-stream' },
});
const reader = resp.body.getReader();
const chunks = [];
while (true) {
  const { done, value } = await reader.read();
  if (done) {
    break;
  }
  chunks.push(value);
}
const buffer = new Uint8Array(chunks.reduce((acc, chunk) => acc + chunk.length, 0));
console.log(buffer.length); // 512

Common questions

What if I want to name my main app file something other than App.js?

You can set the "main" in package.json to any file within your project. If you do this, then you need to use registerRootComponent. The export default will not make this component the root of the app if you are using a custom entry file.

For example, you want to make src/main.jsx the entry file for your app and organize all of your app's source code in src directory. You can set this in package.json:

{
  "main": "src/main.jsx"
}

Then, in src/main.jsx, make sure you call registerRootComponent and pass in the component you want to render at the root of the app:

import { registerRootComponent } from 'expo';
import { View } from 'react-native';

function App() {
  return <View />;
}

registerRootComponent(App);