AgentSkillsCN

vice-sources

为屏幕业务逻辑与响应式状态管理，创建 ViceSource 模型。

SKILL.md
--- frontmatter
name: vice-sources
description: Create ViceSource models for screen business logic and reactive state management.
argument-hint: "[task] - e.g., 'create UserModel', 'explain ViceSource pattern'"
context: fork
allowed-tools: Read, Edit, Write, Glob, Grep, Bash(./format, ./gradlew *)

ViceSource Skill

Create ViceSource models for screen business logic and reactive state management.

When to Use ViceSource

Use ViceSource when:

  • •Screen needs reactive business logic
  • •State transforms based on repository data
  • •Complex async operations in screen context

Use Behavior Model (simple @Inject) when:

  • •Pure validation/formatting
  • •No reactive state needed
  • •Stateless transformations

ViceSource Pattern

kotlin
@ScreenScope
class UserModel @Inject constructor(
  private val userRepository: UserRepository,
) : ViceSource<UserState> {

  @Composable
  override fun currentState(): UserState {
    val users by userRepository.observeUsers()
      .collectAsStateWithLifecycle(emptyList())

    return UserState(
      users = users,
      isLoading = users.isEmpty(),
    )
  }
}

data class UserState(
  val users: List<User>,
  val isLoading: Boolean,
)

Integration with Compositor

kotlin
@ScreenScope
class UserCompositor @Inject constructor(
  private val userModel: UserModel,
  private val navigator: Navigator,
) : ViceCompositor<UserIntent, UserViewState>() {

  @Composable
  override fun composite() = with(userModel.currentState()) {
    UserViewState(
      users = users.map { it.toUiModel() },
      isLoading = isLoading,
    )
  }

  override suspend fun onIntent(intent: UserIntent) {
    when (intent) {
      is UserIntent.UserClick -> navigator.navigateTo(UserDetails(intent.userId))
      is UserIntent.Refresh -> userRepository.refresh()
    }
  }
}

Multiple Sources

kotlin
@Composable
override fun composite(): MyViewState {
  val userState = userModel.currentState()
  val settingsState = settingsModel.currentState()

  return MyViewState(
    userName = userState.name,
    isDarkMode = settingsState.isDarkMode,
  )
}

Testing ViceSource

Use moleculeFlow + Turbine:

kotlin
@Test
fun `state updates when repository emits`() = runTest {
  val repository = FakeUserRepository()
  val model = UserModel(repository)

  moleculeFlow(RecompositionMode.Immediate) {
    model.currentState()
  }.test {
    awaitItem().isLoading shouldBe true

    repository.emit(listOf(testUser))

    awaitItem().users shouldBe listOf(testUser)
  }
}

Documentation