In-App Java Example

This example shows how to write custom java code in android/app/src and call it using jnigen generated bindings.

How to run this example:

• Run flutter run to run the app.

• To regenerate bindings after changing Java code, run flutter pub run jnigen --config jnigen.yaml. This requires at least one APK build to have been run before, so that it's possible for jnigen to obtain classpaths of Android Gradle libraries. Therefore, once run flutter build apk before generating bindings for the first time, or after a flutter clean.

General steps

These are general steps to integrate Java code into a flutter project using jnigen.

• Write Java code in suitable package folder, under android/ subproject of the flutter app.

• Create A jnigen config like jnigen.yaml in this example.

• Generate bindings using jnigen config.

• Add an externalNativeBuild to gradle script (see android/app/build.gradle in this example).

• Add proguard rules to exclude your custom classes from tree shaking, since they are always accessed reflectively in JNI.

• Build and run the app.