awesome-java-android-agent-skills

Expert guidance on structuring a Java-based Android application using Clean Architecture, feature modularization, and dependency injection with Hilt. Use this when asked about project structure, module layout, or DI in a Java codebase.

Expert guidance on building an offline-first data layer in Java using Room, Retrofit, and the Repository pattern. Use this when designing repositories, DAOs, DTO-to-entity mapping, or cache strategies.

Expert guidance on implementing MVVM in Java using Jetpack ViewModel and LiveData with unidirectional data flow. Use this when building screens, wiring Fragments/Activities to state holders, or reviewing MVVM code in Java.

Expert guidance on writing and maintaining Android Gradle build files in Groovy DSL for a Java project — product flavors, signing configs, build types, and dependency management. Use this when configuring build.gradle for new modules or flavors.

Expert guidance on setting up GitHub Actions CI for a Java Android project — JDK 17, Gradle caching, lint, unit + instrumented tests, signing, and Play Publisher. Use this when creating or tuning CI pipelines for a Java-based Android app.

Expert guidance on using java.util.concurrent (ExecutorService, ThreadPoolExecutor, Futures, ListenableFuture) on Android from Java. Use this when designing background work, custom thread pools, or cancellation-aware pipelines.

Expert guidance on Retrofit 2 + OkHttp 4 from Java — services, converters, interceptors, call adapters, timeouts, and error body parsing. Use this when building or reviewing the networking layer in a Java Android app.

Expert guidance on RxJava 3 for Android — Observable, Single, Flowable, schedulers, disposables, and error handling. Use this when building reactive pipelines or maintaining existing RxJava code in Java.

Step-by-step migration from deprecated AsyncTask to modern java.util.concurrent and WorkManager. Use this when modernizing legacy Java Android code that still uses AsyncTask.

Mechanical, safety-oriented migration from findViewById to Jetpack ViewBinding in a Java Android codebase. Use this when modernizing an older project that still uses findViewById throughout Activities, Fragments, and adapters.

Expert guidance on optimizing a Java Android Gradle build — configuration cache, R8 optimization, resource shrinking, parallel execution, and remote build cache. Use this when build times regress or APK/AAB size bloats.

Expert guidance on auditing a Java Android app's runtime performance with Android Studio Profiler, StrictMode, Layout Inspector, and GPU overdraw. Use this when investigating jank, slow startup, ANRs, or memory leaks.

Expert guidance on Android UI testing in Java with Espresso, IdlingResource, Hilt test rules, and Robolectric for fast JVM UI tests. Use this when writing instrumented tests, replacing flaky sleeps, or setting up a hermetic UI test harness.

Expert guidance on unit testing Java Android code with JUnit, Mockito, and parameterized tests for ViewModels, repositories, and use cases. Use this when writing or reviewing JVM-side unit tests.

Expert guidance on Android animations in Java using ObjectAnimator, ValueAnimator, MotionLayout, and Transitions. Use this when building transitions, micro-interactions, or shared-element flows.

Expert guidance on using the Jetpack Navigation Component from Java with an XML nav graph, Safe Args, and deep links. Use this when adding screens, passing arguments, or wiring a bottom nav/drawer in a Java project.

Expert guidance on authoring modern Android XML layouts with ConstraintLayout, the Material 3 style/theme system, and proper resource organisation. Use this when creating or reviewing layout, dimens, colors, or themes XML.

Expert guidance on using Glide 4 from Java for image loading, caching, placeholders, thumbnails, and transformations. Use this when loading remote or local images on Android.

Expert guidance on Android accessibility from Java — contentDescription, TalkBack, touch targets, dynamic text sizing, and Accessibility Scanner. Use this when building UI or auditing an existing screen for a11y.

Expert guidance on localizing Android apps from Java — strings.xml variants, plurals, ICU MessageFormat, RTL, and per-app locale. Use this when adding a language, handling pluralization, or enabling runtime language switching.

Expert guidance on using Jetpack ViewBinding idiomatically from Java in Activities, Fragments, and RecyclerView adapters. Use this when wiring XML to Java code, replacing findViewById, or reviewing ViewBinding usage.