Marchuck

class PaginationViewModel(pagedListProvider: PagedListProvider<Person?>) : ViewModel() {

    val pagedListData = pagedListProvider.provide()

    val adapter = SwapiAdapter()
}

Marchuck

@BindingAdapter("android:adapterSetup")
fun setupRecyclerViewAdapter(view: RecyclerView, viewModel: PaginationViewModel) {

    view.layoutManager = LinearLayoutManager(view.context)
    view.adapter = viewModel.adapter
}

Marchuck

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">

    <data>

        <variable
            name="viewModel"
            type="pl.marchuck.pagingexample.pagination.PaginationViewModel" />
    </data>

Marchuck

object PaginationItemCallback : DiffUtil.ItemCallback<Person?>() {

    override fun areItemsTheSame(oldItem: Person?, newItem: Person?): Boolean {
        if (oldItem == null || newItem == null) return false
        return oldItem == newItem
    }

    override fun areContentsTheSame(oldItem: Person?, newItem: Person?): Boolean {
        if (oldItem == null || newItem == null) return false
        return oldItem.name == newItem.name

Marchuck

class SwapiPeoplePagedListProvider(private val factory: DataSource.Factory<Int, Person?>) : PagedListProvider<Person?> {

    override fun provide(): LiveData<PagedList<Person?>> {

        return LivePagedListBuilder(factory, PagedList.Config.Builder()
                .setEnablePlaceholders(false)
                .setPageSize(20)
                .setInitialLoadSizeHint(20)
                .build()
        ).setFetchExecutor(createFetchExecutor())

Marchuck

interface PagedListProvider<Value> {

    fun provide() : LiveData<PagedList<Value>>
}

Marchuck

class SwapiPeopleDataSource(val useCase: GetPeopleUseCase) : PageKeyedDataSource<Int, Person?>() {

    override fun loadInitial(params: LoadInitialParams<Int>, callback: LoadInitialCallback<Int, Person?>) {
        async {
            val items = useCase.execute(page = 1).await()
            callback.onResult(items.orEmpty(), null, 2)
        }
    }

    override fun loadAfter(params: LoadParams<Int>, callback: LoadCallback<Int, Person?>) {

Marchuck

class GetPeopleUseCase(private val api: StarWarsApi) {

    fun execute(page: Int): Deferred<List<Person?>?> {
        return async { transform(page) }
    }

    private suspend fun transform(page: Int): List<Person?> {
        val response = api.getPeople(page).await()

        return response.results ?: emptyList()

Marchuck

interface StarWarsApi {

    @GET("people/")
    fun getPeople(@Query("page") page: Int): Deferred<PeopleResponse>
}

Marchuck

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <TextView
        style="@style/textview_bold"
        android:layout_marginBottom="@dimen/activity_small_padding"
        android:layout_marginLeft="@dimen/activity_default_padding"
        android:layout_marginRight="@dimen/activity_default_padding"