compose-state-generator

Compose State Generator

Generate idiomatic state management code for Compose following UDF (Unidirectional Data Flow).

Coding Standards

MANDATORY: This skill follows kotlin-compose-standards. All generated code MUST comply with these standards:

• Trailing comma EXCEPT for Modifier arguments
• Parameter order: required → Modifier → optional
• Each Modifier method on its own line
• New line at end of file

Quick Start

// UiState
sealed interface ProfileUiState {
    data object Loading : ProfileUiState
    data class Success(val user: User) : ProfileUiState
    data class Error(val message: String) : ProfileUiState
}

// ViewModel
class ProfileViewModel(
    private val userRepository: UserRepository,
) : ViewModel() {
    private val _uiState = MutableStateFlow<ProfileUiState>(ProfileUiState.Loading)
    val uiState: StateFlow<ProfileUiState> = _uiState.asStateFlow()
}

Decision Tree

What kind of state?
├─ Screen-level state → ViewModel + UiState
├─ Component-level state → State hoisting or remember
└─ Shared across screens → SharedFlow or StateHolder

Is there async loading?
├─ Yes → Sealed interface (Loading/Success/Error)
└─ No → Data class with fields

Need one-time events?
├─ Yes → Channel + Flow for events
└─ No → Just StateFlow for state

References

Standard ViewModel Template

class FeatureViewModel(
    private val repository: FeatureRepository,
    savedStateHandle: SavedStateHandle,  // Optional: for args
) : ViewModel() {

    private val _uiState = MutableStateFlow(FeatureUiState())
    val uiState: StateFlow<FeatureUiState> = _uiState.asStateFlow()

    private val _events = Channel<FeatureEvent>(Channel.BUFFERED)
    val events = _events.receiveAsFlow()

    init {
        loadData()
    }

    fun onAction(action: FeatureAction) {
        when (action) {
            is FeatureAction.Refresh -> loadData()
            is FeatureAction.ItemClick -> handleItemClick(action.id)
        }
    }

    private fun loadData() {
        viewModelScope.launch {
            _uiState.update { it.copy(isLoading = true) }
            repository.getData()
                .onSuccess { data ->
                    _uiState.update { it.copy(isLoading = false, items = data) }
                }
                .onFailure { error ->
                    _uiState.update { it.copy(isLoading = false, error = error.message) }
                }
        }
    }
}

Output Location

feature/
├── FeatureScreen.kt        # UI
├── FeatureViewModel.kt     # ViewModel
├── FeatureUiState.kt       # State model (or in ViewModel file if small)
└── FeatureAction.kt        # Actions/Events (optional, if complex)