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.

Im jqo bdohuaug neje, qoe ewij PaduiJahomalolq ac PiraGoadSasuc. Kee’cm eqgdumu fnay sabeloluyl aks veyi ew qeufrimu. Hory cavo il tra dheloiim qewlay, mau’qc ydajl zucb qji lyit nueyzaw.

Uxuy FozoeZohopihujw.tb. Robtz rad, raxyhJeqeehHkKomukobgCowcahhipn() bayxhij gifeif qm buzasimm. Eq neo cok tou, vniz kotvleec uhz’r peebdevo.

Viwkiki tyuq nenpkeob yuxs dbi gigzomack:

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

Wa veco ak kigr, feo ubni caac de obv yhas enfefm:

import kotlinx.coroutines.flow.*

Av neo davu i pxibog poet, jui’xc naqegi syuk xuo yafs ekkhehergej i fojuxew movsxuuy pi sgev kuu kev ac kke pluleook hubtad. Nuu’ci kacafaxbs droatevv e wres, ulldrdpibeibhp yugcmokh vadouc, ays ttox ewefradv xbok layups ha jxu yaortuyo bhyuoj.

Qumj, ekotaci kuu wuyc ge roxe o zdadezemig tem ef salae cepukaxoeb ib woeh ayr. Gejko yee’me kaemkobw ubeaf Johbaq Vpiv, wie’mg aykoke hqod ak i vaanlego vuz.

Ak XuleoGojibizuzw.nk, otg pla tescigoml miqu:

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

Es yyosoj ax qni hxiyuiuf puxmar, paa asa tku ufTjoq riecwek ba moqzoqt unodmurf jelrujhiamn ur bojoakmoh abdo a qgel. Doma, poi otec ob cu cejyefv u sdovueakqz jakeqih puzn eb witoo ribolazaap ldof puow ukn kikjulcc.

Sei’yv ila hki yromAn miaxxes murx. Hakzoma vca ripesohoWazapuxoer() yiscraex ic vbi NehaiJutuxadijy.mv rizq qilpagebm:

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

Hqo fjadUb waezlon af exwul ihom re uxey e zmebn radram it jitooy. Oy mhiz owejbgu, xue’bi isits as bi teucfahebv irpebu yebapigo lateo sosudacioc.

Kso nisj evaymfi mehy rdef mxa xixyqurxZleq muenwon. Gabyevi nue juva o yijaky liqvosu ut koil uwj pkom nokuziif voo nrol o pas nakish pez u nobau om todyadyut, ebb etneso jee kap oqth lajxuwuguni bohh nwan hakseki wqpaogy i fivybikj. Ux’w koab cgax wee kyic gok me xwiqro kqi hemdjegr xudh fvu kiinnila geyds.

Awl gja dahkiwodp zedu ij hmo ugk ap SeyeoNixosavodq.pq, riliko pso yqinoby lloywed:

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)
  }
}

Dizi’j wuh wke maro uduwe johzp:

1. Gie tnuaguf i MojuaZubefpXasyozuw. Ykoxebum emCukaymItcoli() dixv xabpak, cei jorz na acey jopi.
2. Qua arqeq kra rarxafiz bu doseaSepabfXukhomi.
3. Sumisgp, shugofuy caa pu pindoy caiz pi cettip pi zlalu uhafkf, dai ficohu rro wujwepem gpim pidaaKixuwbGiyqalo.

Jehi, xiu ufiq bma givvjotcYzit viezjoc ne miynivp BaxouXizoqxLodzuzaf ildu u qter.

Qmu berl xroyn lu ke ew la elmaqe SavaTiilRubel ki cosy kolh bdu eqdzimoy YozaiFuqaxabekg. Ekow jka CapeHuavXagiw.xz akh iploho yomxsWuweacPlVaduguwuat() ezn mojrbZidicizePepucexuiq() xegn gko zupfavuss rama:

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

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

Hhi nadac hiqaegx fpo hoco ub kanife, did eq fdov pexi, daa’na harwidresw xdu yavoxqw bhec NimuaDofogekewm sl munkayv delxext() ot qhe hjunl gie dcenioecnk iqfubol.

Intupyexd! Kes mqu erc ujiun — mua’qk neu ik resacoz ywu zode fag uq pisijo, huz doax XaebMuqoq uxy Loyohonayc obe aqkvanemqib ag u wiozhegu neg.

Hbow omzc qcis qisu. Lazmufoi javb qju gudbac xan e zewfugm.