R8 Minification Fails Due to Missing java.beans Classes in SnakeYAML

[kanakapalli]

Description
While building the release APK for the example project, the build process fails during the R8 minification step. The error indicates missing java.beans classes that are referenced by the SnakeYAML library. Since java.beans is not supported in the Android runtime, the following error is encountered:

Error Log:

ERROR: Missing classes detected while running R8.
Missing class java.beans.BeanInfo
Missing class java.beans.FeatureDescriptor
Missing class java.beans.IntrospectionException
Missing class java.beans.Introspector
Missing class java.beans.PropertyDescriptor

Steps to Reproduce
Clone the yolo-flutter-app repository.
Navigate to the example directory.
Run the following commands to build the release APK:

flutter clean
flutter build apk --release

Observe the build failure during the :app:minifyReleaseWithR8 task.
Expected Behavior
The release APK should be generated successfully without build errors.

Actual Behavior
The build fails with missing classes during the R8 minification step.

Environment
Flutter version: 3.27.1
Android Studio: 2024.1
Kotlin version: 1.7.0 or above
Android Gradle Plugin: 8.0.0

[UltralyticsAssistant]

👋 Hello @kanakapalli, thank you for submitting a ultralytics/yolo-flutter-app 🚀 Issue. To help us address your concern efficiently, please ensure you've provided all the necessary information outlined below:

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[kanakapalli]

Suggested Workaround: Add R8 Keep Rules

Locate the proguard-rules.pro file under android/app/proguard-rules.pro.
Add the following rules to prevent R8 from removing java.beans and SnakeYAML classes:

proguard

-keep class java.beans.** { *; }
-dontwarn java.beans.**
-keep class org.yaml.snakeyaml.** { *; }
-dontwarn org.yaml.snakeyaml.**
Rebuild the project with the following commands:

flutter clean
flutter pub get
flutter build apk --release

[pderrenger]

@kanakapalli thank you for sharing the suggested workaround. Adding the specified R8 keep rules to proguard-rules.pro is an effective solution to prevent class removal issues during minification. If the issue persists, ensure you are using the latest versions of all dependencies and tools. For further assistance, please verify if these steps resolve the problem and share any additional error logs if needed.