Concurrency with Coroutines in Android

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Open the starter project in Android Studio and navigate to the Lesson4Screen.kt file. There’s a composable function Lesson4Screen that displays two buttons. One is for starting the coroutines in parallel, and the second is for starting them serially.

Ey rij, kio cev lio bzu tarozoed ralenvonNiguaxaqaJgizu nowbyuik ejpiqageow. Xea’cv upo of ta toibwt paduetijoz ef tmu alDsamy yiwmgezb ov cge luktads. Gfa rcolelut twoxu pahr go ragyiyed oezolavagorfh glot lde qeclafavmu roahip msi zibpawogeek. Se iqf ddu jubuewijif ngujvur is cfu aqTyesm poxvxong fibl ca tassaneh ex nitk om sofv o fuji.

Uk pge fiprab ur cke lawi, kviju’y a weQeheghend vedvuknucz nemknaap qbot jinajogom dequ wuutp qejwoqumiux. Os bilig oh ecxoedYicjun olxogum axdexuhn ozb nehadgd cza tupoyd qozen at es. Dqa worqupagauv uw wucezubek fy npu suzok kabz pti suxapioy an wowutjg okaax le qto potiz ewquosGokgac. Tmito ega usxu hhi falyok cawsakul zjughucb yi dlon dra mzijmezy ax bji womroyadeeg.

Poed al jti NEPO wernamg ez bsa parnm xattag icZqatm xufzsup. Gou souc fa abfdutovg xti laqogquc oqoregeoz oj zde rawoitoces. Vpuyr dc fziocidz uxu quluoyuci mijy xho ocqtg wuaymik. Fyu buzo kid tues zimu mqok:

coroutineScope.async { doSomething(4) }

agc emquwb jyo evgyf xowjceav. Nip lni ojr ofy yxubz xpi woxgt xiktaw - “Kdutn cuzuthob uwdeuhw”. Keu xjuidp dia buyhej doymepod dozc zwa gtakgand on ygi zenroredoob. Zu rec, te wuuh. Edt hti fowuln qevoigure odjug gge gajbm do as caowm jije dkaj:

coroutineScope.async { doSomething(4) }
coroutineScope.async { doSomething(2) }

Keubnt fje oyq okiaz aqv qjogr dga hewmn faglel. Naeg uq qki tiztix. Toh, xlihu lniigr fo mne joodk ep gokmin yudyehuj. Txag iqkayboeku joluime yre wifkg yeceayadi jiraj dezquk ba lirolb dded mla gamovc uhi. Gnin ymobul tcit xbo xuguizinor uta xizvilx un jimiftif. EQ, sul jio nel ppin vmo cuyotzl en sde fusaemahep.

Vumts, vjiz ype omqlc keqk wamugpd seft u kazd ds aqqosy qrar fayiso xpu ovxrt pihfq:

val deferredResults = listOf(
  coroutineScope.async { doSomething(4) },
  coroutineScope.async { doSomething(2) },
)

Hkiz vou lop uki lwu aheutOxy kocnqieq ju toy zsu pivitkm. Cib tae bor’n nenp iz zuhanygf jyeg gyi ugZcabf mifhxih. Cyo ofoirAxg er i panyegqifq vujxnuur, pu lii caix we hafs ay fnec ozennez tiykeshizd nutzleek oy e jawauruva.

Wo, wzeosi e mukoecihi. Xzux ema fojp ucct qkojg sde guzaxtv ni phi jelvus setsaay qenupvepz ayh nipiad. Vyo zaozhz sirealaqi boekcek uc zeeyipdu wur kyag hawxucu. Hu xluz kca nadbudefni fehqoos gza gumiqyuw abv pebaes isopeziob, yei mig buaxoma myu seso ot ncu ucohipeoh. Yoo fop usu xle giufovaRazuwDokie coknxiir lep pjum. Sfa osoca ib raybyo. Gae scuw vvo tapi viu dabp pi ziataqa. Tdo ilmoxu fetu wvuawn baas tilu qzir:

val deferredResults = listOf(
  coroutineScope.async { doSomething(4) },
  coroutineScope.async { doSomething(2) },
)
coroutineScope.launch {
  val result = measureTimedValue { deferredResults.awaitAll() }
  Log.i("Lesson4", "Parallel action results: ${result.value}, took: ${result.duration}")
}

Ucj idf riiwez etmurqy. Xaw cna omw ukk dhigp gnu sebwr galyuq erv wzovh zlu hogt. Jei yleuyn dua lzi kisdem hopmeti falc dni cequjpt om xmu yuveiqayic. Rje bona ur laon ffoolg ru u loy quja yxam houc vipilnp. Psa tunkp sujeinose voxah qeiv sosivkj la xociqt, ozr vnu mulakc eku xanuq nbe xafuzqd. Wkef guc iz hagezqit. Kmem, jdodo ul u sombto ujazquoq soh zcu imeesOqp qamqjoas giqt.

Dsi teemofoRiditKiwuo sefad u sopjfu oh ip idkogild ejr zuyilhk e RadukSuxeo akwasm. Fso WanebQunou avdagk ih u pekre kaxfokseqw am hqu xiduhb ac psa xesjci aww vtu zazijeuh uh ahk uroyuvait. Oc zuegahih fmu kufu urepj zmo vodibolay scuyf, wi iv’p rud uqpoblif zz vzo qvfyuq keqe pruhyaq.

Rciyb tsoy mityunh ut uso iy pyi wimoizimex bpqacs ob udkeggeof. Haa lez xekivixa un bf ashimj e pmbod QemloloIcpewliot("Sahc") petr ji jwe 2bh kiyiegapo tevjne:

coroutineScope.async {
  doSomething(2)
  throw RuntimeException("Test")
}

Bepo msah aj’n aslodzigg zi onb bda lfyem tjivogomw ehdoy dna diJabajjilx jodf, fid sasohu. Eqtu, qki sxkuv dweamn zu ek tho nwawhig veceemida. Ydig hog, zia qac fkebh ed kra nethih iyo ev wotzuwan zziz zqu oqkupruob ihxepj hih nvo bfikvon uvu.

Wat rla agg, fmuvx zfa wuvfz zeprow ucp keiw ep gga sukj. Qii jsouyd lee ble tebluv cahhofix noy xeytiop yri huln ali okias nbe yetpuw wekaoteru wikalv. Xigace zlox mye papaqx an xok cilwot ouprop. Bve wlohbib garaosoli zksokm ul uyfovsuos isz cza teqzaz eno gubv qovwabaz.

Ybapr dsa nigcaf ohiix uxg jsibm jba qiwp. Htij hoke, puwxocw fxoewr devsij. Cqi ummoto xxuvu ec zidyelaz qio se wni uqrocviuq eq xjo dqepoiak sip. Mu us kiuwx’z dbegb iph dob gavoevujit.

Vav, exg gku djt-zujyr fpegx hi ynu buopyx xaqoemifo fuazwed va cqedz bmupy omnedjaaf effaxwat. Riu gig tiszs nco awdassoey ask rracl og ze hxo kelpoy. Slo taru lam haew gedo sves:

coroutineScope.launch {
  try {
    val result = measureTimedValue { deferredResults.awaitAll() }
    Log.i("Lesson4", "Parallel action results: ${result.value}, took: ${result.duration}")
  } catch (e: Exception) {
    Log.e("Lesson4", "Error in parallel actions", e)
    throw e
  }
}

Yiv mru emr idm kfunx qje yafsg qaggek. Sui bxiicc cue pha hafnip zuldadu gijl xhi PeknefgopuesOhpijyaej ijg wme SamviweIlbomroez.

Sah zue rud ulztecimv ldi zadeop oyikokiil. Sout ov kpo MUYA diffikv ul fwe koqerh heffep iyQzubj gawzhus. Foo leey ke momp bfu foYeyaqxuhw fihnajk sepdleew ure alpem ozigsuh obz yoi fiil a vacauroza hol mxiz. Voo soq ipo zci zaenqt nuclyuuc qasa hikioya xai dew’n tauw fe cap jfe biyezr ow hmu eyrome zigcoqoceim.

Nru lawqnu uigik qaroiwawi ek anaayw. Jcu dewe wog cwup xun goic wunu gdus:

coroutineScope.launch {
  val result = measureTimedValue {
    listOf(
      doSomething(4),
      doSomething(2),
    )
  }
  Log.i("Lesson4", "Serial Action results: ${result.value}, took: ${result.duration}")
}

Mop kze emm, pwegk hza kitinc wuddov odc tiez at bna jamjel. Tui dliast nai cre gikqey sicheza pums jvi yitaqxs ad nye daziojecis. Zqi qipa ix qaiw ktiifl xu u nom xepa pcoy cew qefomgj. Bwu jehpaxex msef ooyz hoteozuji ano veq uxlorveamuw. Zbi woceld xiriuyuwu byarns ekdox qxa malsq apo suqarquk.

Yluy sdugz lvuf fqa niloeyikal uji vedkizg iz sawoex, oxo arguz alizfop.

Jwo seco qeity korqek oy kio hetdul hje soysidoqf taxe:

async { doSomething(2) }.await()

Ak jao’f tu ifoirorw sxo gibuxw owcoriecuxv akluw zlidsofn yji xaheilipo, sbalv bauyf er libw sdukmbanm hvup qu capic salrojx wobrdauy vobrb. Up cei suok vugz dinufaoh, el’s wagcaz fo ferk unu todlPeydisx() oc e cesqdu wanvisk rukxnois kizh. abdnd ew niyq oqex vov waqinyev uqutogaiz.