Expo Mega Demo

Experimenting with new awesome React Native + Expo features.

Work in progress. More info soon.

A preview video (click the image):

⚠️ Caution! Many features used in this demo are in early, experimental stage and they're not ready for production. Use on your own risk.

Uses Expo custom managed workflow. Prebuilds on Expo SDK 43 pre-alpha template.
All native changes (even these unusual) and patches are covered with config plugins and yarn postinstall script.
Uses Expo Dev Client, react-navigation, ui-kitten
Bluetooth communication using react-native-ble-plx with config plugin
Color picker using Expo GL, made from this tutorial from William Candillon, but rewritten to Reanimated v2
Music Picker is an expo-module written using Swift "Sweet" API. More info soon.
JSI real-time Audio streaming, taken from this PR, thank you Marc!
Player controls stolen from NCL (internal Expo rn-tester equivalent).
FFT is calculated in the JS thread. The spectrum bin heights are written to SharedValues and animated with Reanimated 2.

There is plan to use react-native-multithreading and calculate it in a separate thread. But even without that, the JS keeps around 57-59 fps.
Hardware: Arduino Uno and the HM-10 BLE 4.0 module. Read more in the Hardware README.

How to run

First time:

Make sure you have Expo and all the stuff installed and configured (including Xcode)
yarn install
yarn prebuild
Copy AppDelegate.m from patches dir to ios/expomegademo directory - see below why.
yarn run:ios

Just to start the bundler (without rebuilding client): run yarn start.

Most of them are caused by using very early SDK 43 stuff, which is not yet published, and other published packages are not yet compatible.

expo-dev-client config plugin is not yet working with SDK 43 alpha.
- It hangs the CLI for Android at the dangerousMod -> Main Activity so the -p ios must be added to the prebuild command.
- It messes up the AppDelegate.m. Workign version can be found in ./patches/AppDelegate.m - need to be copied manually.
Frequency bin labels are wrong 🤷. I needed to display them in log scale and I am too lazy to think about how to recalculate everything properly.
Modifying the sound.onAudioSampleReceived callback and the Reanimated 2 stuff requires at least picking the song again to reload properly, sometimes whole app restart is needed.
Does not work on emulator.
Not yet works for Android
- No JSI-related expo-av changes applied.
- The MusicPicker module isn't implemented yet for that platform (there's a copy-pasted expo-haptics code ¯_(ツ)_/¯)

See the postinstall.js script and the plugins section of app.json to see how the patches are applied

patch-package for expo-gl and related libraries - needed, because of migration from @unimodules/core to expo-modules-core
new expo-modules-autolinking requires modules to be specified in package.json dependencies. I don't want to copy my custom native modules to node_modules they are deleted after being copied there by yarn.
by default, expo modules are built with xcframework if available, but that does not work for patched expo-gl, so its xcframework is deleted force build from source.
expo-gl installs wrong expo-modules-core dependency in its own node_modules - it is deleted, the global node_modules one is correct.
expo-cli built-in plugins sets the Push Notifications capability even when expo-notifications are not installed and I see no way to disable it. Another plugin was written to delete that entitlement.
iOS requires another Info.plist value about Media Library usage permission - a config plugin takes care of that
The custom_native_modules directory needs to be added to autolinking paths in Podfile. A config plugin takes care of that.
The AppDelegate.m is being broken by expo-dev-client config plugin, ~~wrote another config plugin to copy the patched file~~ - it does not work, still need to copy it manually.