MVI vs. MVVM in Android Jetpack Compose: Choosing the Right Architecture

Introduction
Jetpack Compose’s declarative UI paradigm has reshaped how Android developers approach state management and app architecture. Two popular patterns, MVI (Model-View-Intent) and MVVM (Model-View-ViewModel), often spark debates about their suitability for Compose apps. In this article, we’ll dissect their differences, strengths, and ideal use cases to help you make informed decisions.

Understanding MVI

MVI enforces a strict unidirectional data flow, emphasizing immutable state and reactive interactions. Its components include:

• Model: Represents the app’s single source of truth (e.g., a data class holding UI state).
• View: A reactive UI (Compose functions) that renders the Model.
• Intent: User actions (e.g., button clicks) that trigger state changes.

How It Works in Compose

1. The View emits Intents (events) based on user input.
2. A ViewModel or State Holder processes these intents, applies business logic, and updates the Model (state).
3. The View observes state changes via StateFlow or Compose’s mutableStateOf and redraws itself.

Example

// State  
data class ProfileState(val name: String = "", val isLoading: Boolean = false)  

// Intent  
sealed class ProfileIntent {  
    data object LoadData : ProfileIntent()  
}  

// ViewModel  
class ProfileViewModel : ViewModel() {  
    private val _state = MutableStateFlow(ProfileState())  
    val state: StateFlow<ProfileState> = _state.asStateFlow()  

    fun processIntent(intent: ProfileIntent) {  
        when (intent) {  
            ProfileIntent.LoadData -> _state.update { it.copy(isLoading = true) }  
        }  
    }  
}  

Understanding MVVM

MVVM decouples the UI from business logic using a ViewModel that exposes observable state. Key traits:

• View: Displays data and sends events to the ViewModel (e.g., via method calls).
• ViewModel: Manages state (using LiveData, StateFlow, or Compose state holders) and handles business logic.
• Data Binding: Optional, but Compose’s reactivity reduces the need for manual binding.