Flutter app to run and profile MNN models on Android (JNI/C++17) with a clean UI, backend probing, and metrics.

• Download: see GitHub Releases — https://github.com/katolikov/MNN_Runner/releases

• Run single or multi-input models with editable shapes.
• Backends: CPU, Vulkan, OpenCL, OpenGL (if the corresponding MNN plugins are bundled).
• High-level profiling metrics only: createInterpreter, createSession, resizeSession, runSession (no per-op timings).
• GPU kernel cache saving for Vulkan/OpenCL.
• Dark mode toggle in-app.
• Inline and fullscreen report viewer with output shapes.

• Place MNN shared objects under android/app/src/main/jniLibs/<ABI>/:
  • Required: libMNN.so
  • Optional plugins (ship only what you use): libMNN_Vulkan.so, libMNN_CL.so, libMNN_GL.so, libMNN_Express.so
• The app loads plugins lazily on demand. We do not auto-load libMNN_Express.so to avoid linker warnings when a system copy exists but is not accessible to the app namespace (Android P+ isolated namespaces).
• OpenCL: ensure your libMNN_CL.so defers loading the vendor driver via dlopen internally. We do not link libOpenCL.so directly.

• adb shell uses a global linker namespace and may find vendor libs; apps run in isolated namespaces and cannot.
• Ship all required .so files with the APK or link only against NDK-public system libs.

./scripts/push_libs.sh [arm64-v8a|armeabi-v7a]
# On device: export LD_LIBRARY_PATH=/data/local/tmp/mnn/<ABI>

• Install Flutter and run:
  • flutter pub get
  • flutter run -d android (or -d macos, -d ios, -d web)
• Analyze/lint: flutter analyze
• Format: dart format .
• Test: flutter test

• Android 15/16: use scripts/screenshot_android.sh to build, install, launch, and capture a screenshot to docs/screenshot_android.png.
  • Usage: scripts/screenshot_android.sh [serial]
  • Pass a device serial if multiple devices are connected: find with adb devices.
  • Ensure an emulator or device on Android 15/16 is connected and unlocked.

• Ensure android/app/src/main/jniLibs/<ABI>/libMNN*.so exist for the ABIs you target.
• Build: flutter build apk --release
  • Output: build/app/outputs/flutter-apk/app-release.apk

Note on minSdk: modern Flutter (3.24+) recommends minSdkVersion >= 21. Vulkan also requires API 24+ on most devices. Building for API 16 is not supported by current Flutter + plugins. If you absolutely need API 16, you’ll have to fork the project and rework the toolchain and feature set (e.g., disable modern backends and update Gradle/Flutter), which is out of scope here.

Repository: https://github.com/katolikov/MNN_Runner

1. Ensure native libs are committed under android/app/src/main/jniLibs/.
2. Tag a version (e.g., git tag v1.0.0 && git push origin v1.0.0).
3. The provided GitHub Action builds a release APK and attaches it to the tag’s Release page.

We include a simple workflow under .github/workflows/android-release.yml. It builds a release APK on tagged pushes and uploads it as a release asset. You can adjust Flutter version as needed.

• Add a main app screenshot to docs/screenshot.png for the README preview.
• Optionally add more under docs/screenshots/ and reference them here:
  • ![Home](docs/screenshots/home.png)
  • ![Report](docs/screenshots/report.png)

• JNI expects the MNN headers under android/app/src/main/cpp/third_party/MNN/include and libMNN.so per-ABI under android/app/src/main/jniLibs/<ABI>/.
• Dart MethodChannel name is mnn_runner; method runModel expects a JSON with keys modelPath, inputShape (or inputShapes), backend, memoryMode, precisionMode, powerMode, threads, inputFill, and flags profile, cache.