Why Should You Wrap LiveData With Your Own Abstraction

Presentation.kt

interface ObservableViewState {
    fun observeTitle(lifecycle: Lifecycle, observer: (String) -> Unit)
}

interface IScreenPresenter : ObservableViewState {
    fun loadData()
}

class ScreenPresentationState : ObservableViewState {
    private val titleLiveData = MutableLiveData<String>()

    override fun observeTitle(lifecycle: Lifecycle, observer: (String) -> Unit) {
        titleLiveData.observe({lifecycle}) {
            it?.let(observer)
        }
    }

    fun updateTitle(newTitle: String) {
        titleLiveData.postValue(newTitle)
    }
}

class ScreenPresenter(
        private val state: ScreenPresentationState
) : IScreenPresenter, ObservableViewState by state {
    override fun loadData() {
        state.updateTitle(getSomeHowTheTitle())
    }

    private fun getSomeHowTheTitle() = "this is just example"
}

class ScreenView : AppCompatActivity() {
    @Inject lateinit var presenter: IScreenPresenter

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        presenter.observeTitle(lifecycle) {
            // render somehow the title 
        }
        presenter.loadData()
    }
}