In the Android official Lifecycle library, a consumerProguardRule is included. It tells Proguard to keep all subclass class names that implement or inherit LifecycleObserver or DefaultLifecycleObserver:
This leads our projects to unnecessarily expose a lot of code names that use DefaultLifecycleObserver. But in fact, for the subclasses of DefaultLifecycleObserver or FullLifecycleObserver, they don't need to be kept at all, and they can be completely obfuscated, because the Lifecycle framework doesn't reflect FullLifecycleObserver at all. Unfortunately, the Android official kept them all. Once we introduce the Lifecycle library, its consumerProguardRule content will inevitably be automatically merged into our project Proguard configuration and take effect.
This GitHub project solves the problem.
在 Android 官方提供的 Lifecycle 库中，包含了一个 consumerProguardRule，它告诉 Proguard 需要 keep 住所有实现或继承 LifecycleObserver 或 DefaultLifecycleObserver 的子类类名:
这导致了我们不必要地暴露了很多使用到 DefaultLifecycleObserver 的代码命名，但实际上，对于 DefaultLifecycleObserver 或 FullLifecycleObserver 的子类，它们根本不需要被 keep 任何内容，它们都是可以完全混淆的，因为 Lifecycle 框架并不会对 FullLifecycleObserver 进行任何反射，可惜 Android 官方一股脑全给 keep 住了。一旦我们引入 Lifecycle 库，其 consumerProguardRule 内容将不可避免地自动合并到我们的工程 Proguard 配置中并生效。
这篇文章提供了一个简单快速的解决办法：https://t.zsxq.com/VzNfmyb