coroutine demonstration

sample_presenter_fetch.kt

class CoroutinesPresenter(private val dispatcherProvider: DispatchersProvider,
						private val repository: Reviewsrepository) {

	private val job = Job()
	private val uiScope = CoroutineContext(dispatcherProvider.main + job) //runs on main thread

	fun fetchData(count: Int, page: Int) {
		try {
			uiScope.launch {
				arbitraryView.setLoading(true)

				//switch to IO thread
				val reviews = withContext(dispatcherProvider.io()) {
					repository.fetchReviews(count, page)
				}

				arbitraryView.updateReviewsList(data)
			}
		} catch(e: Exception) {
			arbitraryView.updateUiForError(e)
		} finally {
			arbitraryView.setLoading(false)
		}
	}

	//or any function that depicts the presenter is getting destroyed or detached from view
	//this will be on Cleared in arch component ViewModel
	fun onDestroy() {
		job.cancel()
	}
}

data class DispatchersProvider(
	val io: CoroutineDispatcher = Dispatchers.IO,
	val main: CoroutineDispatcher = Dispatchers.MAIN,
	val computation: CoroutineDispatcher = Dispatchers.DEFAULT
)