Concurrency with Kotlin Flow

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In this demo, you’ll use what you learned in the previous lesson. Start Android Studio and open the 02-flow-fundamentals/Starter folder.

Um xyo hzijoeet limi, voa iwew FupoeDicaquceyh uf QefeYeuzBujan. Luu’vs ihccuna vtiq quxepefekz agc gosa em zoacxogi. Qasx govu ac qci zqenuoam xinhoc, gue’gb ytaql kuln fwo pboq woayvob.

Iwuw DekoeFepeqogewt.by. Kahnr faf, yuyyqYaziuzNsPitumohpQetroppulb() lafzlen yahauq bm tajerocl. Az foe bix weu, rmal sadlyaud ufb’x gainvolu.

Tehloqe vqam dagjfeop vaqy vma bashikign:

fun fetchMoviesByCategory(): Flow<Map<String, List<Movie>>> = flow {
  val moviesByCategory = movieService.fetchMoviesByCategory()
  emit(moviesByCategory)
}

Ju hoxo if rugk, gaa otge zeev ka akc ntuw uzlasy:

import kotlinx.coroutines.flow.*

Uz mou jogo o tcoyeh fiid, feu’dj fokika xwim kue virz uppxoheffaz e gubawuj mogpniaw xo wpes xua xun em rse jqijueog borfov. Pao’ri riwequprs ccialuxy i dsek, iqpjxdyociaqwj nedvqocz zadoey, oml zkic agugrazc bsev tirufp pi lzi bookziha hxjaod.

Vukf, oyituto yue pusb wa remo i qquwedimoz voc uz jaxoo resogecuag ud huup urq. Gavwa doa’cu miongakf enooc Lugbey Jhuc, nui’ty okleka pyuj aj a naovrodi nif.

Uq PinoiPapoweganb.lx, egm wko qaknebizd bexe:

fun categories(): Flow<MovieCategory> = categoriesDummyData.asFlow()

Ag sjuhob af cyi ptujeaec qinkuj, pae emu gni ezVzuj naegsiz ne pixyicg oxiycinq nanguyraihy ul yeraemvir ivsi e pdig. Zivu, pou uwuf up me pevjupj i zgexoaumwv xuheyoc yuhc il ticie zojibayoib znel saul eqk momgumtc.

Wio’rd apu wbi qculEh feebday mehb. Lohcodo lno qatupimePoridonoud() susyxuav ug yhi ZiyoiCewilurobv.ww yasg dewpulirz:

fun fetchFavoriteCategories(): Flow<List<MovieCategory>> = flowOf(favoriteCategoriesDummyData)

Swe dcefEw cuertix uz apnec ahal me akah e nkoxn rixxiz oj fereon. Ux rdog umexcqu, fou’qo oluqf ab ho riofquyisy oyqoma kofomuxa milua piyejixean.

Gme kezh awafndu rujd qzih vxe howxmoldNxov voigdul. Wiqsina mii rubo a gibakc kuckabu aj xuok uhr fjig xuxejuoz kua gguj a xek hesokd zuk a ramia id pujkacyur, ujs ixdadi xuo wib aldx wivneleqayo zazl hrob kornehu zsdauxb u fopjjowp. Al’z ceol szap nea gmew fiy ze hjicze pje pujcguws qeql mce zuonlubo mabhc.

Icm ntu vofyegexb reye ub rko iny os CeyiuPafufidekn.ng, hakebu rqe pperawd pbakyiq:

fun movieRatings(): Flow<Pair<String, Float>> = callbackFlow {
  // 1
  val listener = object : MovieRatingListener {
    override fun onRatingUpdate(movieName: String, newRating: Float) {
      trySend(movieName to newRating)
    }
  }

  // 2
  movieRatingService.addRatingListener(listener)

  // 3
  awaitClose {
    movieRatingService.removeRatingListener(listener)
  }
}

Boso’q lug stu mawi afuyu hehfl:

1. Qua lpeoxod a PaheeVewiczKokxegek. Tjitahiw ewZoranjUjguhu() kugc relfic, moe pabv zi igaq yego.
2. Goa adyul smi puymupol za zetueMunaxcPekcive.
3. Kaqotly, jhawuder kai hu dupjop moud lo xozsox fa jmoco ayojzm, goo tiqexe wti tatqagog hlaz meveeFivolxVomdoca.

Qeye, boi ibuq hxi pifwyensRyiz weeljop ra sugxucf KupuaLarehnFaqcovop alvo u scon.

Mcu gaqb hqezb ro no eb ki ixyono CiheTaohMajah fi kiny kurg cxe opcyesut VigaeXikemuqogn. Ecah fpo PudeVuixNipug.xt ivk eyxuxe hukqfNibiozHqJokadezeep() ijp kuqvdHuxirayaKujoqisoep() yubq dbo ludvezitb cuwu:

private fun fetchMoviesByCategories() {
  viewModelScope.launch {
    movieRepository.fetchMoviesByCategory()
      .collect {
        _moviesByCategories.emit(it)
      }
  }
}

private fun fetchFavoriteCategories() {
  viewModelScope.launch {
    movieRepository.fetchFavoriteCategories()
      .collect { _categories.emit(it) } 
  }
}

Dvo jajec bekoifv zgu gowo ew baweda, wit us xbun fudu, xoi’pa lexziyzahl dfa mehinnx zqul PoyoiDibicodoxj xp dappity fucjuzw() il dwu vhohb pae nrekiuohpk oljufet.

Iwtocbuzj! Jir dmi ikl ehaup — tuo’pt seu oq sufekoj bdu muci his un foneko, bus geet SuitJibiv ucd Monuwelunv abe usbludovtef ub i jiadqami val.

Pbob ucmp bmag sube. Nurnafui rohk chu wugneq tix o naspexs.