Demo Android Modules

This project demonstrates how to integrate Android native modules into an Expo React Native app.

The main issue centers on integrating a third party .AAR Android library file into an Expo Build (CNG)

• See reference Android project here

• Docs for Expo instructions

Prerequisites

Before getting started, make sure you have the following installed on your machine:

• Node.js (v18.20.0+)
• Expo CLI (v6.3.10+)
• EAS CLI (v7.6.2+)
• Android Studio

Getting Started

Follow these steps to create and run the project:

1. Clone the repository:

   git clone https://github.com/your-username/demo-android-modules.git

2. Navigate to the project directory:

   cd demo-android-modules

3. Install dependencies:

   yarn install

4. Build and run the Android app:

   yarn android

5. (optional) Open the android directory in Android Studio.

6. Build and run the project using the Android emulator or a physical device.

Demo Initialization Steps

1. yarn create expo-app -t expo-template-blank-typescript

2. Test build works using npx expo run:android --no-build-cache

3. create a local native module: npx create-expo-module --local demo-datacap

4. Import the native module to run consume it in App.tsx

5. Run npx expo run:android --no-build-cache and verify app is working with native integration

6. Run npx create-expo-module --local demo-datacap

   • .aar file located at: demo-android-modules/modules/demo-datacap/android/libs/DSIEMVAndroid.aar
   • Create a Kotlin wrapper around the android/libs/DSIEMVAndroid.aar library file
   • This build.gradle and expo-module.config.json setup does not appear to work when running npx expo run:android --no-build-cache

Contributing

Contributions are welcome! If you find any issues or have suggestions for improvement, please open an issue or submit a pull request.

License

This project has no license for use other than debugging build issues.

Bugs

Issue 1

Development build (npm run android) succeeds but fails when running the native code using the example button

Error:

JNI DETECTED ERROR IN APPLICATION: JNI GetObjectRefType called with pending exception expo.modules.kotlin.exception.MissingTypeConverter: Cannot find type converter for '(kotlin.String) -> kotlin.Any'.

java_vm_ext.cc:591]   at expo.modules.kotlin.types.TypeConverter expo.modules.kotlin.types.TypeConverterProviderImpl.obtainTypeConverter(kotlin.reflect.KType)

Issue 2

Production build (npm run build:production:android) does not work

[RUN_GRADLEW] FAILURE: Build failed with an exception.
[RUN_GRADLEW] * What went wrong:
[RUN_GRADLEW] Execution failed for task ':demo-datacap:bundleReleaseLocalLintAar'.
[RUN_GRADLEW] > Error while evaluating property 'hasLocalAarDeps' of task ':demo-datacap:bundleReleaseLocalLintAar'.
[RUN_GRADLEW]    > Direct local .aar file dependencies are not supported when building an AAR. The resulting AAR would be broken because the classes and Android resources from any local .aar file dependencies would not be packaged in the resulting AAR. Previous versions of the Android Gradle Plugin produce broken AARs in this case too (despite not throwing this error). The following direct local .aar file dependencies of the :demo-datacap project caused this error: