2dog.android 4.8.0.193

2dog.android

Initial, experimental Android host support. Godot's Java Activity owns the surface, render thread, input, pause/resume and shutdown; the .NET app registers its runtime before launching it. Do not use the desktop Engine.Start() loop on Android.

dnx 2dog add --android scaffolds such a host. By hand: reference 2dog.engine, this package, and the 2dog.android-arm64 and/or 2dog.android-x64 meta packages. Choose Debug or Release with TwoDogVariant and an explicit Android RID. Both native variants retain the JNI name libgodot_android.so; exactly one belongs in each ABI directory of the APK.

Set GodotProjectDir to the Godot project, and dotnet publish -r android-arm64 produces a signed package. dotnet publish builds Release, for which .NET Android makes an app bundle (.aab) unless the host sets <AndroidPackageFormats>apk</AndroidPackageFormats> (the showcase does) or you publish with -c Debug. The build:

• imports the project and exports its pck with the project's Android export preset (TwoDogAndroidExportPreset), using the same capability as desktop publish: the build machine's editor libgodot from the 2dog.<rid>.editor and 2dog.tools packages that 2dog.engine brings, or GodotEditor. TwoDogAndroidPack supplies a pre-exported pck instead;
• puts every Android library and dependency that the project's .gdextension files list for the APK's ABIs and variant into lib/<abi>/, where the engine loads it (TwoDogAndroidGdExtensions=false opts out);
• adds the pck as the APK asset game.pck, which TwoDogActivity loads.

Only android-arm64 and android-x64 are supported; any other RID fails with TDGA013. Mark the Android preset runnable=false: a runnable Android preset starts the editor's ADB device poll during the headless export, which logs an EditorSettings error when it exits.

Signing follows established conventions only:

• .NET Android's AndroidKeyStore=true with AndroidSigningKeyStore, AndroidSigningKeyAlias, AndroidSigningStorePass and AndroidSigningKeyPass always wins (env: and file: password prefixes keep secrets out of logs);
• otherwise Godot's export variables GODOT_ANDROID_KEYSTORE_RELEASE_PATH, _USER (the key alias) and _PASSWORD (GODOT_ANDROID_KEYSTORE_DEBUG_* for debug builds). 2dog maps them onto the .NET properties and hands the password over as an env: reference, so it never reads the secret;
• otherwise the Android SDK's debug keystore, debug.keystore in ANDROID_USER_HOME or ~/.android (alias androiddebugkey, password android), which Android Studio and Gradle sign debug builds with, so 2dog builds install as updates over theirs;
• otherwise .NET's own debug key (in its Xamarin/Mono for Android settings directory).

Release builds that fall back to a debug key say so.

TwoDogAndroidSigning=false turns the variable mapping off.

demos/showcase/showcase.android is the complete example; tests/android/host is the minimal one. Both include the Java dependencies Godot needs (AndroidX Fragment, DocumentFile, Kotlin standard library) and extracts the game DLL into private app storage before AndroidHost.Register. Registration happens in Application.OnCreate, including when Android recreates the Godot Activity directly after process death. Release builds trim and AOT-compile with .NET for Android's defaults (TrimMode=partial, profiled AOT); TrimMode=full and AndroidEnableProfiledAot=false work too. The package roots GodotSharp, GodotPlugins, twodog and TwoDogAndroidGameAssembly for the trimmer. Native AOT (PublishAot), experimental in .NET for Android, links with the NDK (AndroidNdkDirectory); 2dog then roots only GodotSharp and the game assembly. CoreCLR (UseMonoRuntime=false), also experimental there, fails with TDGA006.

Host code reaches the scene through TwoDogActivity.addMainLoopStartedListener(Runnable): Godot runs each listener on its render thread (the engine's main thread) once the main loop has started and the main scene is in the tree. Register from Application.OnCreate via JNI. A listener that throws is logged (tag TwoDogActivity) and the others still run; handle exceptions in the listener to report them your own way. demos/showcase/showcase.android uses it to drive scene nodes once per frame (SceneTree.ProcessFrame) and to run the showcase's API smoke.

Build prerequisites: .NET 10 with the android workload, JDK 17, Android SDK 36, build tools 36.1.0, and NDK 29.0.14206865 (see the pinned Godot submodule config). CI builds the Android natives (arm64/x64, debug/release) and the Java AARs into the godot-<hash> natives release; its pack job packs the 2dog.android* packages from them. Neither build needs Mono glue. The pinned Godot submodule includes the Android native-symbol resolver changes; rebuild the managed bindings from that source before testing. To build everything locally:

uv run build-godot.py # desktop editor and managed bindings
uv run build-godot.py --platform android --arch arm64
uv run build-godot.py --platform android --arch x86_64
uv run scripts/build_android_java.py
uv run poe pack-android
uv run poe build # pack desktop dependencies and the managed engine with AndroidHost

Then publish a host and run it:

dotnet publish tests/android/host/android-smoke.csproj -c Debug -r android-x64 -o artifacts/android
uv run scripts/test_android_device.py artifacts/android/dev.twodog.smoke-Signed.apk --serial emulator-5554

scripts/publish_android.py wraps the same publish: --format aab builds an app bundle, --pack supplies a pre-exported pck, and signing properties can be passed using repeated --property NAME=VALUE arguments; use normal .NET Android keystore configuration for distributable builds. No store upload or NuGet push is performed.

Run uv run poe test-android-build for Android build and package tests. The APK smoke test validates C# callbacks, signals, node disposal and a rendered pixel on an Android 36 x64 emulator. The showcase APK adds the main-loop hook, a 3D scene and a plain C GDExtension loaded from the APK's native library directory. Input, pause/resume, restart, broader GDExtension coverage and physical-device validation remain gates before production support. The Android workload and emulator are not required for the build and package tests. The separate tests/android/android.slnx keeps Android workload requirements out of ordinary desktop solution builds. The Android packages ship to NuGet with the others, and the Android Smoke job gates deploy. ForcePackAllPlatforms cannot pack empty Android packages.

APK implementation milestones

1. Build both native variants for one ABI, build both Java AARs, pack a private local NuGet feed, and publish a signed smoke APK (the publish exports the C# scene). Inspect the final APK for the exact selected native libraries, one ABI, the PCK and the extracted game-assembly asset. The private feed also contains desktop dependency stubs and must never be published.
2. Run that APK on an x64 emulator. The scene verifies signals, native node lookup, deferred disposal, 32 C# frame callbacks and a green rendered pixel before reporting success. CI's Android Smoke job builds this APK and the showcase's against the packed packages and runs both; the showcase must report 2DOG_ANDROID_SHOWCASE_SMOKE_PASSED. It uploads them as android-apks, with an arm64 showcase APK for devices.
3. Add Android engine tests for touch input, background/resume, Activity recreation, process death and repeated launches, with per-test results and crash diagnostics. Use Android-owned lifecycle fixtures and the existing *Tests naming convention.
4. Validate Debug/Release on physical arm64 hardware, AAB-derived APKs and a 16 KB page-size environment before expanding the supported RID list.

With source-matched GodotSharp/editor release outputs staged, an installed Android workload, and ANDROID_HOME/JAVA_HOME pointing to the SDK/JDK, build-android-apk packs a private feed from the staged payloads, publishes a host against it exactly like dotnet publish above, and inspects the APK:

uv run poe build-android-apk

The pck export uses the editor libgodot packed from godot/bin, or --editor <godot mono editor>. Use --rid android-arm64 or --configuration Release for the other target. --skip-native --skip-java reuses already staged payloads. --feed <dir> publishes against already packed packages instead of packing them (CI passes its nuget-packages, with its android-natives staged in godot/bin/android/ for the APK inspection). The resulting APK and inspection report are written to artifacts/android-apk/. --app showcase publishes the showcase host instead (into artifacts/android-showcase-apk/); its GDExtension needs an Android NDK (ANDROID_NDK_ROOT, or one under the Android SDK).

References: Godot Android library, .NET Android build items.