MainPresenter.kt

class MainPresenter(private val view: MainView,
                    private val dataProvider: DataProviderAPI
                    private val uiContext: CoroutineContext = UI,
                    private val ioContext: CoroutineContext = CommonPool) {
 
    private fun loadData() = launch(uiContext) { // use the provided uiContext (UI)
        view.showLoading()
 
        // use the provided ioContext (CommonPool)
        val task = async(bgContext) { dataProvider.loadData("Task") }
        val result = task.await()
 
        view.showData(result)
    }
 
}