Class showing the key points of Presenter layer in MVP

MainPresenter.kt

// Presenter has the object of both View and Model(Interactor)
// Implements OnFinishedListener to listen for Interactor response
class MainPresenter(private var mainView: MainView?, private val mainInteractor: MainInteractor)
    : MainInteractor.OnFinishedListener {

    fun getData() {
        mainView?.showProgress()
        mainInteractor.requestGetDataAPI(this)
    }

    override fun onResultSuccess(arrUpdates: List<DataItem>) {
        mainView?.hideProgress()
        mainView?.setData(arrUpdates)
    }

    override fun onResultFail(strError: String) {
        mainView?.hideProgress()
        mainView?.setDataError(strError)
    }

    // Destroy View when Activity destroyed
    fun onDestroy() {
        mainView = null
    }
}