This “Missing classes detected while running R8” error usually happens during the release build of a Flutter/Android app. It means that R8 (the shrinker/obfuscator for Android) cannot find some classes referenced in your code or in third-party libraries (like Agora, Zego, Firebase, etc.).
To fix this error find out missing_rules.txt file located at “build\app\outputs\mapping\release” directory which contains the keep rules for the classes that R8 couldn’t find .
Now copy the rules from missing_rules.txt and paste it to proguard-rules.pro file located at “android/app” directory .
After adding the rules clean the project and try to build the apk . This time apk will be build successfully
flutter clean
flutter pub get
flutter build apk --no-tree-shake-iconsIf you like this article , please like , comment and share the article . You can also buy me a coffee.