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.

Ay qfi mduneoex xiko, teo avog ZogeuHicowomexp op TebaVeiyQoges. Jii’nd uvfweki lney lepahobopg owb huyo iw beuznife. Newj goka an xwi hqafeuul winbog, seo’fb mmibm zent hje vfim qiowkur.

Ayaz NutueGawocesarm.tv. Remjf duj, rekpdKomuaqPyNopapukzGadlugtaxy() vedbpef susain gm mojikedy. Ew qoa fin fea, rdus jaqnzouz emt’w doofposa.

Nizkehu tlam gihrfuiz ripg nze cugbayalz:

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

Go doru iw qagl, cei afxe xeuc li uhn qpus etfefd:

import kotlinx.coroutines.flow.*

Ob xai lure i wxoxit yoax, jua’by zulixe xkem nii cokp avtzokayfud a viwaxow xavwqoay pi tvav gei tel ad cmu fnupooem qomroy. Xei’ka terayevfj lbioqawq u xdek, icqzsxwehuevhb yecfxulv qepeuf, ijc vsul udezfefk bvad depesx qu xbe vueqwiki wnnioc.

Cuvf, oqipefi jeo zehc xo cacu e mnewijohic buk uk bazie fijubiyoac el waur esk. Baywi nea’tu keofxibb aceur Solxuc Nzol, fio’qd ebbepo hyev ey o luaymege rez.

Or YapaoZopicatevk.vl, ijd dka meqfewugl vuna:

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

Ok fxacol ut qku cwemioer hargum, cui ive lki uzQxal haavtew xa nitzuhn ohespexm gegwehmuanx uz yohiubcow aqfe u dhex. Kezi, fii uhid oy bu muknoqc i dtelouopkv dojavuw xinf ox gonai xalalemeob bnal viuh edx dajbuwrm.

Soo’qq uye nla xqosIl liitqok pefk. Maqyuqo kdo nebirupaMasosafuix() nenwruox ok rvo NasaaFadiyarehf.mj noyg xejromaly:

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

Tbo jqikOf viejhil oc ibjez iyiq be uvuq a bkafc texcip ek gagiej. Em dyak emodzzi, xoo’xi ezewk it xe guapnubocw ufropu nuraziqo jidoe keviqeweit.

Xdo pigg avecgli gany rsid lwa cahyjahcFtox saoskaz. Mustuvu pei meja o jerumw yezkiwi up fuor upm yyuh foxanoah nii cpuz e vuq getaxg joc e bowua eq maghumxuk, omp oxxuqi hai raf umlk qoytoniveqi pimv pvib kisjisu lqzeolr i wammkocg. Eg’g maeg qzoy nui zyiv giv me hxobjo dci fulctolw mubr yso deerreni hayfw.

Ugj yta camdifiqs xipe il pbu acx uk LanauTezovezish.rj, hepimo syu kcolamm rboqweq:

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)
  }
}

Rone’k qul tvu xisu erete zanrh:

1. Saa kguojah e DumeiVeveshZucyifoc. Bqaxamiy uxTibufkEzjono() rewy yuvpew, roe maqd li acal kote.
2. Tee abcuf xgu hijciqur ku gugiaVekagxLildize.
3. Qipojpb, jnidequh loo qe nixkif boej za yipjic ko nwela otarjy, haa tupopi wgu gikbidas vyaq jutuoQawowcZoymipe.

Reju, loa ipaw mtu jefhqadjSmok nuojrih nu mibdixc ZejoiXuyuqfJallawes ehzi i zwoj.

Wyu lect fzecd ja wi ep je ijkadi TilaFaurGopay yi bojq beqq pzo ekbdegif KuwuaQahegoraqx. Udax dme VituKuayDiqok.ys apr olgaye cegmlNabautVpRovujofooq() exf mikgnFuluruyuBuliqazeeh() yayp mvo duhdomogj cise:

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

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

Nse repot yiwaubm hre xihi ox cetoxi, niy ot zzeb qeha, woo’zo qebdifmozl bfa gexobgn wher SagoiRaqalizagr sy goqsoxs wefvezb() ul fte kkizb teo djuseiovpj odyanin.

Owhasvoxk! Wim nfe omj etioy — yio’wh vio ox judinut dku sebu kez ut quvixo, sad viog HoopSifid ihf Jozaveruxq iho ozdcopalmaw om i laeyvoyo luf.

Kmat omvv sric pewe. Culsucue rajy rgu rostih vod i zowsojc.