/android-support-j4rs

Primary LanguageJava

Android support code for Rust written in Java

Demonstrating how to:

  1. Compile some Java code against android.jar;
  2. Create a .dex file from the resulting .class 1;
  3. Build an APK containing the .dex file and some Rust code in a .so;
  4. Call a static class function in the aforementioned class from Rust code via jni.

Usage

  • Install xbuild from a WIP branch with "dex packaging support":
cargo install --git https://github.com/rust-mobile/xbuild --branch classes-dex

  • List the emulators: $ANDROID_HOME/emulator/emulator -list-avds

  • Start the emulator: $ANDROID_HOME/emulator/emulator -avd AVD_NAME

  • List running devices: x devices

  • Create the dex intermediate file from j4rs:

$ANDROID_HOME/build-tools/34.0.0/d8 ./j4rs-0.19.0-SNAPSHOT-jar-with-dependencies.jar --intermediate --file-per-class --output ./dexed-j4rs.jar --lib $ANDROID_HOME/platforms/android-33/android.jar
  • Create the classes.dex
$ANDROID_HOME/build-tools/34.0.0/d8 ./dexed-j4rs.jar
  • Run: x run -p example --device adb:<device identifier>

Footnotes

  1. Expecting that this is later extended with user code, jar files etc, all these raw inputs should likely be passed to xbuild in manifest.yaml so that it can call d8 to combine everything at once. ↩