Notes App

A 2-screen note-taking Android app built with Jetpack Compose, following clean architecture with feature-layered modularization. Uses Koin for dependency injection.

Architecture

:app                          ← Application, MainActivity, nav wiring
:build-logic                  ← Gradle convention plugins
:core:domain                  ← Result, Error, DataError, UiText (pure Kotlin)
:core:presentation            ← ObserveAsEvents, UiText extensions, DataError.toUiText()
:core:design-system           ← AppButton, AppTextField, AppCard, AppIcons, theme
:feature:notes:domain         ← Note, NoteError, NoteRepository interface
:feature:notes:data           ← Room DB, NoteDao, RoomNoteDataSource, repository impl
:feature:notes:presentation   ← ViewModels, State/Action/Event, screens, nav routes

Dependency rules

• presentation → domain, core:*
• data → domain, core:*
• domain → core:domain only
• :app → everything

Screens

1. Note List — shows all notes (LazyColumn), FAB to create, delete via icon, tap to edit.
2. Note Editor — create/edit note with title + content fields, save & delete, process-death restoration via SavedStateHandle.

Build

Requires Android SDK and a JDK 17.

# Generate the Gradle wrapper (once, with Gradle installed)
gradle wrapper --gradle-version 8.5

# Assemble debug APK
./gradlew :app:assembleDebug

# Run unit tests
./gradlew :feature:notes:presentation:test
./gradlew :feature:notes:data:test

Key patterns

• MVI: State / Action / Event (only when one-time side effects exist), Root/Screen composable split.
• Result wrapper: Result<T, E> with DataError and feature NoteError.
• Koin: per-layer modules (notesDataModule, notesPresentationModule) assembled in NotesApplication.
• Type-safe navigation: @Serializable route objects + feature nav graph.
• Accessibility & responsiveness: content descriptions, 48dp touch targets, font-scale & width previews, light/dark theme.