JoseAlcerreca

class MyViewModel(authManager..., repository...) : ViewModel() {
    private val userId: LiveData<String?> = 
        authManager.observeUser().map { user -> user.id }.asLiveData()

    val result: LiveData<Result<Item>> = userId.switchMap { newUserId ->
        liveData { emit(repository.fetchItem(newUserId)) }
    }
}

JoseAlcerreca

class MyViewModel(...) : ViewModel() {
    val result: StateFlow<Result<UiState>> = flow {
        emit(repository.fetchItem())
    }.stateIn(
        scope = viewModelScope, 
        started = WhileSubscribed(5000), // Or Lazily because it's a one-shot
        initialValue = Result.Loading
    )
}

JoseAlcerreca

class MyViewModel(...) : ViewModel() {
    val result: LiveData<Result<UiState>> = liveData {
        emit(Result.Loading)
        emit(repository.fetchItem())
    }
}

JoseAlcerreca

class MyViewModel {
    private val _myUiState = MutableStateFlow<Result<UiState>>(Result.Loading)
    val myUiState: StateFlow<Result<UiState>> = _myUiState

    // Load data from a suspend fun and mutate state
    init {
        viewModelScope.launch { 
            val result = ...
            _myUiState.value = result
        }

JoseAlcerreca

<!-- Copyright 2020 Google LLC.	
   SPDX-License-Identifier: Apache-2.0 -->

class MyViewModel {
    private val _myUiState = MutableLiveData<Result<UiState>>(Result.Loading)
    val myUiState: LiveData<Result<UiState>> = _myUiState

    // Load data from a suspend fun and mutate state
    init {
        viewModelScope.launch { 

JoseAlcerreca

<!-- Copyright 2020 Google LLC.	
   SPDX-License-Identifier: Apache-2.0 -->
   
@HiltAndroidTest
@UninstallModules(CoroutinesModule::class)
@RunWith(AndroidJUnit4::class)
class AgendaTest {

    @get:Rule(order = 0)
    var hiltRule = HiltAndroidRule(this)

JoseAlcerreca

<!-- Copyright 2020 Google LLC.	
   SPDX-License-Identifier: Apache-2.0 -->

@InstallIn(ApplicationComponent::class)
@Module
object TestCoroutinesModule {
    @DefaultDispatcher
    @Provides
    fun providesDefaultDispatcher(): CoroutineDispatcher =
        AsyncTask.THREAD_POOL_EXECUTOR.asCoroutineDispatcher()

JoseAlcerreca

<!-- Copyright 2020 Google LLC.	
   SPDX-License-Identifier: Apache-2.0 -->

open class MainTestApplication : Application() {

    override fun onCreate() {
        // ThreeTenBP for times and dates, called before super to be available for objects
        AndroidThreeTen.init(this)

        Timber.plant(Timber.DebugTree())

JoseAlcerreca

<!-- Copyright 2020 Google LLC.	
   SPDX-License-Identifier: Apache-2.0 -->

// With Dagger2 or dagger.android
class MainTestApplication : MainApplication() {

    override fun applicationInjector(): AndroidInjector<out DaggerApplication> {
        return DaggerTestAppComponent.builder().create(this)
    }
}

JoseAlcerreca

<!-- Copyright 2020 Google LLC.	
   SPDX-License-Identifier: Apache-2.0 -->

@CustomTestApplication(MainTestApplication::class)
class CustomTestRunner : AndroidJUnitRunner() {
    override fun newApplication(cl: ClassLoader?, name: String?, context: Context?): Application {
        return super.newApplication(cl, CustomTestRunner_Application::class.java.name, context)
    }
}