Gist 3 - Android Example

DataApiService.kt

object DataApiService {

    fun loadData(): Observable<DataModel> {
        return Observable.just(DataModel("data_model"))
    }

    fun loadAnoteherData(): Observable<AnotherDataModel> {
        return Observable.just(AnotherDataModel("another_data_model"))
    }
}

DataModels.kt

data class DataModel(val id: String)

data class AnotherDataModel(val id: String)

data class FullDataModel(val data: DataModel, val anotherData: AnotherDataModel)

DataRepository.kt

object DataRepository {

    private var data: FullDataModel? = null

    fun saveFullData(data: FullDataModel): Completable {
        return Completable.fromAction { this.data = data }
    }
}

LoadingDataPresenter.kt

class LoadingDataPresenter(private val view: LoadingDataView) {

    private val api: DataApiService = DataApiService

    fun loadData() {
        updateLabel(R.string.loading_data)
        getFullData()
            .doOnNext { saveFullData(it) }
            .subscribe(
                {
                    updateLabel(R.string.data_loaded)
                    view.loadingDataProgressBar.visibility = View.GONE
                },
                {
                    updateLabel(R.string.load_data)
                    view.loadingDataProgressBar.visibility = View.GONE
                    view.showToast(R.string.error_message)
                }
            )
    }

    private fun updateLabel(resId: Int) {
        view.loadingDataTextView.text = view.getString(resId)
    }

    private fun getFullData(): Observable<FullDataModel> {
        return Observable.zip(
            api.loadData(),
            api.loadAnoteherData(),
            BiFunction { data: DataModel, anotherData: AnotherDataModel ->
                FullDataModel(data, anotherData)
            }
        ).subscribeOn(Schedulers.io())
    }

    private fun saveFullData(data: FullDataModel) {
        DataRepository.saveFullData(data)
            .subscribeOn(Schedulers.io())
            .subscribe()
    }
}

LoadingDataView.kt

class LoadingDataView : FrameLayout {

    constructor(context: Context) : super(context)
    constructor(context: Context, attrs: AttributeSet?) : super(context, attrs)
    constructor(context: Context, attrs: AttributeSet?, defStyleAttr: Int) : super(
        context,
        attrs,
        defStyleAttr
    )

    init {
        View.inflate(context, R.layout.view_loading_data, this)

        val presenter = LoadingDataPresenter(this)
        setOnClickListener {
            loadingDataProgressBar.visibility = View.VISIBLE
            presenter.loadData()
        }
    }

    fun getString(resId: Int): String = context.getString(resId)

    fun showToast(resId: Int) {
        Toast.makeText(context, resId, Toast.LENGTH_SHORT).show()
    }

}