Levi-Moreira

import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.view.View;

public abstract class ClickableAdapter<VH extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<VH> {

    private ClickItemListener clickItemListener;

    public void setClickItemListener(ClickItemListener clickItemListener) {
        this.clickItemListener = clickItemListener;

Levi-Moreira

    implementation "android.arch.paging:runtime:$paging_version"
    implementation 'android.arch.paging:rxjava2:1.0.0-alpha1'

Levi-Moreira

    
    //ViewModel, LiveData and LifeCycle
    implementation "android.arch.lifecycle:extensions:1.1.1"
    implementation "android.arch.lifecycle:runtime:1.1.1"
    implementation "android.arch.lifecycle:reactivestreams:1.1.1"
    kapt "android.arch.lifecycle:compiler:1.1.1"
    
    //rx java2
    implementation 'io.reactivex.rxjava2:rxandroid:2.0.2'
    implementation 'io.reactivex.rxjava2:rxjava:2.1.14-RC1'

Levi-Moreira

class StackOverflowConfig {

    companion object {
        const val SERVER_BASE_URL = "https://api.stackexchange.com"
    }

    var serviceCreator: Retrofit

    var apiService : StackOverflowAPI

Levi-Moreira

interface StackOverflowAPI {
    @Headers("Content-Type: application/json", "Accept: application/json")
    @GET("/2.2/users")
    fun getTopUsers(
            @Query("page") page: Int,
            @Query("pagesize") pagesize: Int,
            @Query("order") order: String = "desc",
            @Query("sort") sort: String = "reputation",
            @Query("site") site: String = "stackoverflow"

Levi-Moreira

class UsersDataSourceFactory @Inject constructor(
    val api: StackOverflowConfig
) : DataSource.Factory<Int, User>() {
    var observableEmitter: PublishSubject<UsersDataSource> = PublishSubject.create()
    override fun create(): DataSource<Int, User> {
        val usersDataSource = UsersDataSource(api)
        observableEmitter.onNext(usersDataSource)
        return usersDataSource
    }
}

Levi-Moreira

class UsersDataSource @Inject constructor(
    private val soApi: StackOverflowConfig
) : PageKeyedDataSource<Int, User>() {
    var loadState: PublishSubject<NetworkState> = PublishSubject.create()
    var disposables: CompositeDisposable = CompositeDisposable()
    
    override fun loadInitial(
        params: LoadInitialParams<Int>, 
        callback: LoadInitialCallback<Int, User>
    ) {

Levi-Moreira

class UsersRepository @Inject constructor(
    var dataSourceFactory: UsersDataSourceFactory
) {
    fun getUsers(): Observable<PagedList<User>> {
        val config = PagedList.Config.Builder()
                .setInitialLoadSizeHint(SO_PAGE_SIZE)
                .setPageSize(SO_PAGE_SIZE)
                .build()
        val users: Observable<PagedList<User>> = 
        RxPagedListBuilder(dataSourceFactory, config)

Levi-Moreira

class TopUsersViewModel @Inject constructor(
    val usersRepository: UsersRepository
) : ViewModel() {
    fun getUserList(): LiveData<PagedList<User>> {
        val result = usersRepository
                .getUsers()
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .toFlowable(BackpressureStrategy.BUFFER)
        return LiveDataReactiveStreams.fromPublisher(result)

Levi-Moreira

class UsersAdapter : PagedListAdapter<User, UsersAdapter.UsersViewHolder>(
    UsersDiffCallback()
) {

    lateinit var clickListener: (User) -> (Unit)

    override fun onCreateViewHolder(
        parent: ViewGroup, 
        viewType: Int
    ): UsersViewHolder = UsersViewHolder(