Expo Modules

Adding native code to our React Native apps

Agenda

History and background
EAS build and dev client
Expo modules demo

React Native as an interface

#javascript
alert("hello world")

#swift
Alert(
    title: Text("Current Location Not Available"),
    message: Text("Your current location can’t be " +
                  "determined at this time.")
)

#java
val alert = dialogBuilder.create()
alert.setTitle("AlertDialogExample")
alert.show()

Expo Go

React Native + Expo packages

Expo SDK picks up where React Native core libaries end
Audio, barcode scanning, camera, calendar, etc. etc.
What happens if you need access to additional native functionality?

Development builds

Like your own version of the Expo Go client
Can add native code!
Installing native modules
What happens if there's no good React Native package yet?

React Native modules

React Native Bridge
Expo Modules

Demo!

Demo Review

npx create-expo-modules
Development workflow
- building in the example app
- Xcode for iOS, Android Studio for Kotlin
- Needs to be a separate package
- Deploy using Github actions
- Adding dependencies

Resources

https://docs.expo.dev/workflow/expo-go/

https://docs.expo.dev/workflow/using-libraries/

https://docs.expo.dev/build/introduction/

https://docs.expo.dev/development/introduction/

https://docs.expo.dev/modules/overview/

React Native Modules

https://reactnative.dev/docs/native-modules-intro

https://medium.com/@dev_one/react-native-native-modules-ee5a8f390a7

Expo Discord

https://discord.gg/89c8pE34

Example repo

https://github.com/alxhghs/example-expo-module

Expo Modules

By Alex Hughes

Expo Modules

51

Alex Hughes