Can you explain the differences between the MVP and MVI architectural patterns?

MVP (Model-View-Presenter) and MVI (Model-View-Intent) are architectural patterns used for organizing code in applications, especially on Android, but they have different approaches to state management and component interaction.

MVP:

• View is responsible for display and user interaction.
• Presenter contains logic, handles user actions, updates the View.
• Model includes data and business logic.
• Presenter directly updates the View, often through interfaces.

MVI:

• View generates Intents (user intentions).
• Intents are passed to the Model, which processes them and returns a new state.
• View subscribes to the state stream and updates based on it.
• It is a unidirectional data flow architecture, simplifying state management and making it predictable.

Main difference: MVP uses bidirectional interaction between View and Presenter, while MVI employs a unidirectional data flow with immutable state, which facilitates debugging and testing.

Example of a simplified MVI in Kotlin:

sealed class Intent {
    object LoadData : Intent()
}

data class ViewState(val data: String, val isLoading: Boolean)

class Model {
    fun process(intent: Intent): ViewState {
        return when(intent) {
            is Intent.LoadData -> ViewState(data = "Data loaded", isLoading = false)
        }
    }
}