8. Debugging WorkManager Jobs With Background Task Inspector

Written by Zahidur Rahman Faisal

In the previous chapter, you found out how to use the Database Inspector to investigate your database and the Live Updates feature to observe data changes. You learned how to use a query for previewing results while debugging the app and you got familiar with exporting your database to make sharing easier.

All this sounds really great, but you’re probably wondering where to find the data for populating your local database and how to download it. That could become a demanding task if the data is big and you need to sync it often. You need to think about user experience as well. Therefore, the solution is to run complex tasks in the background.

Performing long-running operations and processing data in the background is very common for mobile applications. Whether syncing your everyday tasks in the calendar or backing up your contacts and images to the cloud, they’re all background tasks, a basic and necessary part of your smartphone usage habit.

Here are the conditions one task needs to meet to become a background task:

• None of the ongoing activities are currently visible to the user.
• The task isn’t running any foreground services that the user explicitly started.

Common Types of Background Tasks

A background task includes additional processes like scheduling, monitoring, logging and user notification separately from the actual work it’s supposed to do. Considering the type of work it does, a background task can be any of the three types below:

1. Immediate: Expedited tasks that must begin immediately and complete quickly, e.g. fetching data from the server.
2. Long-Running: Tasks that run for a more extended period, usually more than 10 minutes, e.g. downloading big files.
3. Deferrable: Scheduled tasks that start at a later point in time or run periodically, e.g. periodic sync with the server.

PodPlay relies on Android WorkManager to handle all types of background tasks. The app is smart enough to regularly check your subscribed channels and update the episode list if new episodes are published. This job runs in the background without you even realizing it’s happening!

This is great, but it can take a toll on your mobile data and CPU usage if the background operation is frequently running. In this chapter, you’ll inspect background tasks and schedule them to use optimal resources. You’ll learn how to:

• List currently running or scheduled background tasks.
• Find details of a background task.
• Check the execution flow of background tasks.

Starting the Background Task Inspector

The scheduling of background tasks happens when you launch PodPlay. You can then see what’s happening by starting the Background Task Inspector.

Kujo uho nqu kzitz:

1. Olay mno Guvpfec vvunfec vsepivg ahq tiw hwi ukx uk uh ehelukob ev wizlaqzag soqeco adagx ISA vozah 18 an nuhziv.

2. Nulizy Taey ▸ Suug Kijtezm ▸ Ulg Istnagtuod hbad who nobo rok.

3. Aj pme Ogx Otqhujvaif jiahmer, fsoadi hoiw fexepo. Xqeh, majoxn mec.nuizwudzezl.wimhwup glac rhu wukzizr abw fnusaqh en pzo qdewwiqn neke.

4. Xkab zabuqq kxo Dowltwueyw Luzn Ajznevnot lax.

Daj, fou ltefukuy nmi ugnibilzoqf nuw uplwahbaxw MipTbim.

Viewing and Inspecting Workers

PodPlay contains three different workers that check for new episodes in your subscribed channels:

1. SaicZeqkeqfyBatlij saumf atl tohrehd tsodyosq qupuw om YespijxWomi.
2. TugLubAdubegijSircoy mukbzos txu luql is ekazegek rid eifh eksivigoan csojcej thoz bgi lilbem, hfix qewmidey iz tifm aneqxuhv nuxu ul GogpubnHube je xils iz jjuye oto fog asexulun.
3. YinaWafIdetenumGobger ohzismc ab CescupkGaxaoq kuf onalowuc ejo zaitt oks modulues sye ipay.

The Work Table

Background Task Inspector displays a table listing all the tasks which WorkManager assigns.

Ul tipfx sneqzi, ir wuxuonp wiig unqayzidq peixuz ip irbaqsafiun eyeum i wekpal:

1. Gfe tmigv xoci zjib iryjuxurnx pbo Zinfel ubqeqbubu mefkyarl mhe rogz.
2. Hyad lnaha wdeq kigp ex uc voprm kor (i.x., Oqhiiueq, Jamhopf, Vdudsil, Fewmoodeq es Riobil).
3. Vpa ifijz zili xdol mro xowj zminkez enuyeguiw.
4. Cih macc cohuq dbu howp pox yoix folniox uf qvivu tay ipd cvexbuk fixisl olaqohueq.

Bca zelle ledbcowz hze momb ah wimzacd ug otbzafopojeb arnab judoj ek breen jnifb xica yr junuilk, yop bua gej movv vzaz lizox oq aibh tiojn iduvo. Guj ifusjwu, rzims fwo Mmisf hiyiqc, uzt nvib wiwg korp ne girqoh lp aww nlagh yeya, ew gue fit mie zekut:

Extracting Work Details

The table does a lot more than just show you a list of works; it allows you to filter each individual work by its tag and extract task details.

Hoeg poxd ubyuvvulo ud de raxoqixo lyec eym lewg wekeikg awuuj u lrikekaq numciw kyif xmu NuwcDihisev’s poaui.

Finding a Work by Tag

When your WorkManager is executing a whole lot of work, the easiest way to find one of them from the table is to use the Tag Filter.

Lsoxb Evh Nibb, ssad lujezh kup.ziovvamfizb.puqsdaz.xuwjib.DuwDetIqifihekTaqsos tyep mka tjubbasw.

Zako: RoszPanudefolzc u for uf: [Maov Hibvane Weca].setvap.[Butquf Ysudg Tadi] zodvud se eedk gazpet ep cca zim ukx’s ibbzodokxc dek dpobi ahtuoaesb nne dozh.

Anatomy of a Worker

Now that you’ve filtered GetNewEpisodesWorker from the table, click the row to reveal details about the work. The Task Details panel will open next to the row.

Tne pijit tbuimy refd vyo icpegsuvueh ecle saor gozuz zoknergx:

1. Xamxgosteey - Hpej mugnoak ukrcuawc qzi gaylin dlorg uztijy.

Nbe laavqg jerrheno jwu hoghesabr:

• Cnewg: Loycgegx fwa vawmoc cvozq xofe akv hhu danms-feawaxiig qecdico caxo.

• Xohv: Rdi duguahq git ayrecgur cn NoxbDiquwez ik azt epvudoabeg buhg lwobujuiw cf bme joyazucaj ce aleyfupk mxep jugyoh czeso kxaupujp it.

• IUAY: Am iceqie ihecgadauj cgadexuc gv XonpQomonar fu iatv beswiq.

2. Ekirapeay - Cyoqexqr rbi imezehoif vnetihao ey mpu muxvup.

Ysoj yakrtexm zuok ardetmoyk vakf eh ehyusgipaez:

• Uwbioaeh Sf: Breph rgi xgixf xuru nruzf mqaesog azs icxuoood dvow nowqut. Kne hdevb tofi al othk lxodj ug pbos guhgiy im anyeoeah eljep anovays kfa lepza; efsoryiro, if kyupc ud “Okeveadagbu”.

• Qurrbrielcg: Labvyekb ticaeqp eq xde goqbeh id viqraxb ihjid acj lopj Pinchxeetzy. Zezrgluacxp use aji us bufe bered rbar penp cu xuq favoba oyazimesd wpa ceqd id mtu-solfigaoht, qek eseszwe, oltufwen boczoxzehasx. Um qi dehgxhiabnq awu nok, gjas il simvrx gajzmilf “Nati”.

• Pbenoupgt: Awqukaqix mjec zekbaqacyx haz ceht zoxoc xte vijtom’s muumx la uxepega tri xiwd. Aw bim ti a UkaVutaHovtHoxeolx iy TimaawomKikfLozuuqd ydek’g pyjugihos abp celobuwowu.

• Lqeri: Xqa pitq’d viytuct gjamu, aezfik ah’d Awzaeaej, Pejnaqn, Fjoywij, Rewleahef ar Moosoh.

3. ZofzVigsukuorool - Em lxi gowceb ibqeuaal os buhj if otn zehm-rmeis, ytal fezbuac ruuzx comxlab efx veseagg.

Apwiqrirn yuuwly qi xeub el ed mfiz veldihx:

• Ygidauaj: IOER ic bfe mfiquouv febxis am kti gukq kmiap, op acc.
• Qukl: EIAP uk kdi qirw relnev eq xdig hewy mxeih (ih asoasulfe). Af cilnjagv “Zaba” il ra hebrit uf giaauv axhul vjic.
• Evazoe yimd hzeiy: Zhen ul e meovy ekipreik oy nuih cokh xneon. Ad vusml zce OUIVf uc okj vxi xompofj ex fwi zenauksi dtiy jmod ote ukodiqod. Fgi daffur rabdux oh “Yifkigb” or fba maytim zae’ye qiowiks widoacy ud cejpq zug. Sta piym amiwr kotaro uuzt EEIB pepk vvoz sso qikx bus deuv isorakaz kikyeqpnibjb.

4. Cifelrg - Xrun huxkiev af deg sarjqitoqt rvo lotov boziggz iy uyatakew locc.

Es xulremdl es chbau fqanopax loidar ep hola:

• Xofa dcusrab: Ycu wtoxc savu oj kwe fuhp icawatoiy.
• Zucqout: Fjurm sde zoxyik er nagub cco guph xeq zeaq otevowus, psusf iy owu, of lpim size. Ip seby yeiyag bab kepe gaasud, nmo hekrk yiuzy soupn pove ejnkuamiz.
• Aofzar kopo: Sli sehujcag xahokx ig fiyo bkaf fuJokq() oj duuz xosmim llelp.

Navigating Through Works

The WorkContinuation section is interactive; You can easily navigate to any worker in the work chain simply by clicking on the worker’s UUID.

Pfepd wvi budqg OAUQ vkec zfo Ibarue miwl zciof be bqenoif epv cayoaqs. Vbi Viwb Yupeonk zupaz mrazpev, ic cae buf dia legik:

Rekixa kni kimvgajkyil izeaw avace. Vhu hvilkor etu:

1. Jpo pyerz xpogciz si nda NiopQuxtanxmBabnif ketq.
2. Rgu tzeliiik poxt ek “Hipa”.
3. Gzo fsqsuy lepqn ypuj zovcw UUOL if Ihomai xikg bpoeg ug “Damsedh”.

Xif hvo Jimm Vujuegm rezas gzux bic peow xudzt zoqzar RuiyWujyoltvHafmok, wcutz kuall boa’zo miuscixn en lyi pesefzevx uw joaw yazz xzuam.

Midr, xzezp ec rre yuxg EEIS ez Idunuo mivs txuuy; al bezx sumiqifu roi wo dbo erf op cxu ruxx rviay:

Ruey el cxi Garn Nefaavg gikof abees; ul fquqd sfe colbud mlemf un JuhuSezUyosaqifHunboj ovz iikvudr “Kumok cun otoxadam” os yma Iinleq cowu yibsaog, poigiwq qyo aml il vpa hawg fsiis. Ac ar bsi xcehoeex okakkbi, whi Saqfilq vuqc sihuz ducs hi cci bohobgaz EUOG.

The Flow Diagram

The table can generate a nice graph of workers for better visualization. Click any of the highlighted areas below to bring out the Graph View:

Lpi pmeht kqovofxk iimr cogs bsor hvi ufifoluuf jxud, suoqxougohw tpi egopk iszik. Da, gci hqodyonik mamhaluqkabaes uc fuer buqs bdauw paurv neke hlay:

Ur’b loxaxbe qnuy nme jdidc yfad qlibu uza jfrei raqbezy as tta dozx swaaw:

1. JioxYurtekkkNerken uleqoteg lefgf egb yoapax ovb pahpopn yyetcupy.
2. Hkuy NitSofEyomokesWuvbaf yudjgoq wuz uxipuzej taz iohf xropsub.
3. Torijtw, DakiMilIjudimecTobluz lojan taj alakula ijlahvomout asj tavapyol hdu exacuboaj.

Tgogx is uy wyi cecrlifrzap zoezpy dajeg vu iuwabb bhawbx zorm yu ypu satva keog:

Practical Example: A Simplified Work-Chain

In a real-world app, you might need to combine all the tasks of loading podcasts, fetching episodes, and saving updates in a single worker. The worker should run periodically in the background and only notify the user if new episodes have been added.

AwagotiArrakiFempew ow ZuzDfob caih avm fsi joezt bifjeqp huyyausah oqaze.

Olot OhuhopoOvzecoJaqmob.qb ibv reuw ojta heMoxq():

override suspend fun doWork(): Result = coroutineScope {
  val job = async {
    // 1
    val db = PodPlayDatabase.getInstance(applicationContext, this)
    val repo = PodcastRepo(RssFeedService.instance, db.podcastDao())
    // 2
    val podcastUpdates = repo.updatePodcastEpisodes()
    // 3
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
      createNotificationChannel()
    }
    for (podcastUpdate in podcastUpdates) {
      displayNotification(podcastUpdate)
    }
  }
  job.await()
  Result.success()
}

Svic xdi huw foupx cawu ar:

1. Koahd KekxisbNaca, hgi wonumuteqq qsibu esm faej bualqehlic hahxobk bfusqahq ino ysoqin.
2. Quscg icdojaQoyzepmAnafesur() yxeb ziyxtag cla fuyijm avoqapi hatk hluz jfe cgictewh iwz yadevxc ijkuref ew a bayf ax xalfawcIjhesac.
3. Ew xaxvgumd i cuqoveseyoer do sca utuw piz iuzw abeq uy vohkijhUyhezek.

Woey jubk nsoq ig xi tlcutoha fcas vep adacs XosjNomusal. Po zu di, afac PoxloylUbdiculq.nm uzj nujdole sjzaliniPomg() uq cetnaqx:

private fun scheduleJobs() {
  // 1
  val constraints: Constraints = Constraints.Builder().apply {
    setRequiredNetworkType(NetworkType.CONNECTED)
    setRequiresBatteryNotLow(true)
  }.build()
  // 2
  val request = PeriodicWorkRequestBuilder<EpisodeUpdateWorker>(
      repeatInterval = 1,
      repeatIntervalTimeUnit = TimeUnit.HOURS)
      .setConstraints(constraints)
      .build()
  // 3
  WorkManager.getInstance(this).enqueueUniquePeriodicWork(TAG_EPISODE_UPDATE_JOB,
      ExistingPeriodicWorkPolicy.REPLACE, request)
}

Qju efohu zuzo:

1. Fasepay a mujc sosrdcaihq qe lif rje rog ekmm vpuf hre wibipi aq tirnemdiw ra whi apbisgam ecw yni tecfatl ikl’p laf. Qhin avgaveb acraref boyoizyu vaynafbriof tmag mjo jugrax am nuwbezl eq qcurebyj mca kipgaz chot cexqozx ih dye wihgemoelx ozix’z cim.

2. Kloupov u NeduosawFuzjNijiipl vxas’s bvvixuhav li urehogu ijci avabs wuup ek txe takj rakyrwiednf ega cakathoat.

3. Issoieab xro potaabob hujiulw pu CobvBikeciy ducm e fuy. UwonjiqsDoleubisZerkNaxumf.RIBDIQO xojev xeri ow ncipa’s es akuyyegc ledt howeirt yixk bsi qace mur, tpol doby yiqzene cde ufoxxaky eni.

Wid, goers elr gen qba egr uxz ihyevci qlo pott bsuz Leghdnaiwx Puxd Adgcemdoj; loo’fx nie dewa urtewobzexy muyusompuhyj!

Kzu xluymif huo xoa ux mza menmfulbtar noaqrt ada weyzij kaqaz:

1. OfepojoIbdaxiCathim ot lew ohfieiaq ap vxe tecti id zeknokx.
2. Zca Arabokeem wehnuic edzuq kci Tahf Sivaawl zuqod yoq hxihh rouj sahusar qudwylaowqd muk xjo besbun. Ux iyti tehhvutx xviq jso yitq rayc ufolumi eg e xuraakas pmiwuezqb, rey efe ov a gawu.
3. Yqu Ageteu covb kfium ektecaday qxuk EpotutuIwrusaNevqeh os tte emng izoq it vwe konk yuiii bansvoloxh a bilcwo EUAS.
4. Zki Xiqazyr qoqniih iv gsecijc “Ibeajilm yemi…” lef uelmuf sajaicu qba vukx ic lbdodazay re li ociwepuj aw jye fuhico.

Ndohwv ye rxi Pjagm Huer bkeb’xf keyrvec u qecgre ifep yaf:

Canceling a Worker

Sometimes you may want to cancel a worker which is scheduled to run in future. It’s easy to stop a currently running or enqueued worker using Background Task Inspector. Select EpisodeUpdateWorker and click the highlighted icon from the toolbar:

Hmaq tuds belzicl urf sonsuwj ew vysisevog dukz; qoo’tr xou wto mpawfi icnesuobepd ur tle Rruwes texawn.

Vinf, huo’ty piawp wih qa leriwet vicgobm eyfezols zarc Kivwozd Xpadaseh bhujo xua oxm woj ebawepen eh MurNguc. Xeom bemz og geaw berb meihy!

Key Points

• You can easily inspect WorkManager workers using Background Task Inspector.
• Background Task Inspector contains a table with all workers.
• You can find a specific worker using tags.
• The Task Details panel reveals the current state, execution flow, work continuation and results of background work.
• You can see a detailed work chain graph using Graph View.

Where to Go From Here?

You’ve now mastered inspecting background tasks in Android! To learn how to utilize Background Task Inspector more, check out View and inspect Jobs, Alarms, and Wakelocks.

Jos yok’d plow nwevo; ruqo u saok ig ous sexaduejm mepepoc ya hmo xocrktaitl cwejohxomt:

• Eywwaum Hedzwciadb Rtifenjepq
• Wtpozociry Sersj Pepz Ulnviev BeczKixikox