How do I enable Facebook login with react native?

Facebook login is a common feature in many mobile apps these days. It allows users to easily sign up and sign in using their existing Facebook accounts instead of creating new accounts specifically for your app. React Native provides a Facebook login API that makes it relatively straightforward to implement Facebook authentication in your React Native app.

Prerequisites

Before you can enable Facebook login in your React Native app, you’ll need a few things:

A React Native app – you’ll need an existing project set up.

Facebook App ID – you’ll need to create a Facebook app in the Facebook developer dashboard to get an app ID.
react-native-fbsdk – this is the React Native wrapper for the native Facebook SDKs that makes Facebook authentication easy to implement.

Step 1: Create a Facebook App

Go to the Facebook for Developers site and log in with your Facebook account. Click on “+ Add a New App” and follow the steps to create a new Facebook app. Take note of the App ID and App Secret that get generated, you’ll need them later.

Step 2: Install react-native-fbsdk

In your React Native project directory, install the react-native-fbsdk package:

npm install react-native-fbsdk --save

This will install the React Native wrapper for the Facebook SDK that makes it easy to integrate Facebook login.

Step 3: Link the react-native-fbsdk package

After installing the package, you need to link it to your project:

react-native link react-native-fbsdk

This will hook up the necessary native code and configurations needed by the Facebook SDK.

Step 4: Configure iOS and Android

There are some additional configuration steps required for each platform (iOS and Android):

iOS Configuration

In your AppDelegate.m, import the FBSDKCoreKit library

Add the Facebook App ID in your Info.plist
Set the Facebook Display Name in Info.plist
Add the LSApplicationQueriesSchemes key with fbauth2 value in Info.plist

Android Configuration

Edit android/app/build.gradle to add the Facebook SDK dependency
Edit android/app/src/main/AndroidManifest.xml to add permissions, activities and metadata

Refer to the react-native-fbsdk documentation for the detailed steps to configure each platform.

Step 5: Add Login Button

With the configuration done, you can now add the Facebook login button to your app. Import the LoginButton component from react-native-fbsdk and add it to your UI:

import { LoginButton } from 'react-native-fbsdk';

// Inside your component
<LoginButton
  onLoginFinished={(error, result) => {
    if (error) {
      console.log("login has error: " + result.error);
    } else if (result.isCancelled) {
      console.log("login is cancelled.");
    } else {
      AccessToken.getCurrentAccessToken().then(
        (data) => {
          console.log(data.accessToken.toString())
        }
      )
    }
  }}
  onLogoutFinished={() => console.log("logout.")}/>

This will render a Facebook login button that will trigger the onLoginFinished callback on tap. In the callback you can handle the response, get the access token etc.

Making API Calls

Once the user successfully logs in, you will get a Facebook access token that can be used to make Graph API calls to fetch user data like name, email, profile pic etc. Here is an example of getting profile information:

const infoRequest = new GraphRequest(
  '/me',
  {
    accessToken: authToken,
    parameters: {
      fields: {
        string: 'email,name,picture'
      }
    }
  },
  (error, result) => {
    if (error) {
      console.log('Error fetching data: ' + error.toString());
    } else {
      console.log('Success fetching data: ' + result.toString());
    }
  }
);

The GraphRequest constructor takes the endpoint (/me to get user profile), the access token and a callback to handle the response. You can make other API calls similarly to get friends list, posts etc.

Additional Features

Some other features provided by the react-native-fbsdk module include:

FBLoginButton – alternative customizable login button component

FBShareButton – button to share content on Facebook
FBLoginManager – low level access to login/logout functions
FBAccessToken – for checking valid access tokens

Check the react-native-fbsdk docs for more details on how to use these components in your app.

Conclusion

Here are the key steps to integrate Facebook login in React Native app:

Create Facebook app and get App ID

Install react-native-fbsdk package
Link package and configure iOS and Android
Use LoginButton component in your UI

Get access token on login and make Graph API calls

Facebook login allows your users to conveniently sign in with their existing accounts. The react-native-fbsdk package wraps the native Facebook SDKs into easy to use React Native components. Integrating Facebook login significantly improves the signup and login experience in your React Native app.

Step	Description
1	Create Facebook App
2	Install react-native-fbsdk
3	Link package
4	Configure platforms
5	Add login button

This summarizes the key steps needed to add Facebook authentication to a React Native app. The react-native-fbsdk package handles all the complexity of integrating with the native Facebook SDKs for you. With just a few lines of code, you can let your users log in with their Facebook accounts.

Some additional pointers:

Remember to set the correct OAuth redirect URI in your Facebook app settings
The LoginButton automatically handles login state and access tokens

Use the Graph API to get profile data and other information about logged in users
Refer documentation for handling token expiration, logouts etc.
Customize the LoginButton appearance and layout as needed for your UI

So in summary:

– Create Facebook App
– Install react-native-fbsdk package
– Link package and configure platforms
– Use LoginButton component
– Handle login callback
– Get access token
– Make Graph API calls
– Customize and handle sessions, expiration etc.

This will enable a smooth Facebook login integration in your React Native app so your users can easily sign in with their Facebook accounts. The react-native-fbsdk wrappers handles the complexity of bridging to the native Facebook SDKs. Facebook login is a must-have feature for most apps these days, and quite straightforward to implement in React Native following the steps outlined.

References

Linking Libraries Android