Below is a simplified example demonstrating the use of MVVM architecture with Coroutine and Retrofit in Kotlin for an Android application. This example assumes you are working on an app that fetches and displays a list of users from a remote API.
Let's start with the project structure:
- Model (User Model): is a simple data class representing a user.
data class Movie(val name: String, val imageUrl: String, val category: String) {}
- API Service Interface (UserApiService): is an interface defining the API endpoints using Retrofit annotations.
interface RetrofitService { @GET("products/1") suspend fun getAllMovies() : Response<ResponseBody> }
- Repository (MainRepository):is responsible for interacting with the API service and fetching user data.
class MainRepository constructor(private val retrofitService: RetrofitService) { suspend fun getAllMovies() = retrofitService.getAllMovies() }
- ViewModel (UserViewModel): is the ViewModel that manages the UI-related data and interacts with the repository using coroutines.
class MainViewModel constructor(private val mainRepository: MainRepository): ViewModel() { }
- View (MainActivity):
class MainActivity : AppCompatActivity() { }
- ViewModel Factory (UserViewModelFactory):
class ContextViewModelFactory(private val context: Context, private val repository: MainRepository) : ViewModelProvider.Factory { }
The MainActivity observes changes in the users LiveData and updates the UI accordingly.
Make sure to add the necessary dependencies for Retrofit, Coroutines, and ViewModel in your project. This example is a basic illustration, and in a real-world scenario, you may need to handle more complex scenarios like pagination, error handling, and loading states.