Migrating AsyncTask to ExecutorService / WorkManager

Instructions

AsyncTask has been deprecated since API 30. It leaks Activities, serializes tasks globally on older devices, and has no structured cancellation. Replace it with either a scoped ExecutorService + Handler or WorkManager depending on the use case.

1. Decision Tree

• Short-lived, tied to a screen (load, parse, save on click) → ExecutorService + ViewModel.
• Deferrable, must run even if the app dies (upload, sync) → WorkManager.
• Reactive pipeline with cancellation-on-recycle → RxJava 3 (see rxjava3 skill).

2. Pattern: In-Activity AsyncTask

Before: