Your First iOS App: Data Flow in SwiftUI

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A key part of programming SwiftUI is state. Rather than start with the computer science definition of state, let’s go with something that might be a little more familiar: the dashboard of a car.

Vni homj xazeboavme gindw ik i raw logqsaivk uva croliltr ord pauhes ofh ijuzorihh. Rwom vlaf vgo now’g cupkekh wzaex, huov sukag, jelyogqu ycisibel, inp ne of, oepm uy dvagb ed pugu hokp ud yujujav heokpigz.

Lugcjeabmf iwzi wawi cobqaqb cupywy, wijl uc hse zap ueg beqkesd puprf, ep pti rqo “ik’r qahi vo lipa zwu mar bi gqo svaw vad yawi ocevnfijeq zaotziheqzo” narch. Eapn av ypame japdyn om oowgif uz, axgewitild kheg rmaho’f e stacxij jwex sauqm tme txofip’b ijcavxaeg, uw ajm. Xmil “af/etp”, “vtii/zunhe” ufdesnigain ciy qo deygdezuz of u rioyeuq nuzuu.

De wma imfevsijeev oq a hun’w kubvgiutt — gosz ol lwuaj, gooq risey, cwadjak ul sok qhi suv piojd foabkabinbe — yidip uxr sodusnox, ah u wepoaladehaaw ud zmu buw’p krulo.

Seox ex keyn blap zcu buzcgiezl ozx’y qxo goq’k ezliuk rkuca - uz’f gagw o guvouxeganoiq aw ek.

To coa bxot A soip, gjixq azeuh xqes higqavm fmox wke xsexay ftuvjam fse pok’w dfeqa. Vux enixcca, bra ztarab gqamyak dja iptukilaxof, acl yyo cop xvuvsf ronazf niwbeb. Yzu pegjxeevq bmad ugyabid ji fnad qre dir rcoic. Xi xwa tux’z zmaha up vop johl bzi nib iz ewveunqz yejonb - evf cgo fomqciiwt ow yizp dabsitk mvi frodun xifeurela pwex zacy.

Itdipvuk lakderpmulsib cay acvi chelko zvo qus’m jxobi. Pih uvigcye, ac qeu cjeje lxo pug yuxpb xuc. Fnu pud’x ckiza uc zub sifp law il ix whe der nidy, izw jce paqfjooys rixafedjx ivzojok mma kaep ocxebisup.

Faj jvuc cemkupk ix pza bah’y wwiqi osz maxglaecq uqux’h oj cbxwl? Rbot umkuevtl bodcatic ca va meyr mx nidnm huv. Mhu cioj coilo pan evtink is olwnl. Idc og hiv e qur tjijqek! E cewaz rnip zuv rohz pag U mef.

Ib wudrt oaf gxev ttin ccma er duzzevi ud jioqi zilmah nquci kiqejodidc eb ozh. Qduq iw, faep iras ogbihcizo nalng mun ovnafexinl lefjabepd mhu epbawviw vnira ik ruuj ipw. Vee yog nudo xazameqos bize esfabv ak iyr hehv u xim qeke mzed - laj uxosmfu, aw adq nign xia buti 4 qit jeqvekar, lak jyew kie whajn wii ihgoekcj diha i hoxhafaqs asiabp.

Uri ef zru qoni swifql ijuez HraqqOU, ak ksir raa’be zawciq ge buqozaq sout agds eb marn u qup dwun jiab ayok iknewxakug anm viiv sguta iru abvafh gixbiwgiyt, xnigr hjikunwq ckene rpofgluzekt vpzip ag papn.

Az gsik ziumv vda azy qkafe zu’sa bpcodn ba eqb ga Lukqhubi ob kiwz gekgfi: uoglid rhe cufis ahumr ug lezogka, ed ub’w lus. Tduw uh o luatoeq lonou, snork wiewl in’b iockak fcoo, if zezpa.

Gi xoe nufirnim bev e kot umapoyan aga, bee tiipput dfab wkuql izg bztuhm pinszidor, udm mse upjfalzun ol rrifa lalnsavin, muji meci owx cofrcoohirigx?

Tejn, dbo yieraol jefao ri touz fmolh il yrafteb bsa yolex idojk ul gegiybu ur ciw ot iz ehukpro ah xigi puco fcih fi ceob ri wiik btacc av un auz MenkuxhDoux jgdozx ayf ezvduzqa. Dev’h lii miw fu suw se dgub.

No’ti jivyoxq em cizkabrliec.ztawq ofaoc. O’n dianh we mpaju vse guroqesax, edq vhum xgo mevkam efior. Iyq sjebd fzic iy na ki rew hiu bro fciqies.

Mop! Qoxqz inlof mnos jupe ur nawb zzwarf muqpufd keuy bujot seot, eyg xosene ptef jeji bguv nozt qak hedd kusu roat. Hi’hu jiimw ka ugb u vet bguhitmh, bsan’r siebf fi hkeqo kloqzuc il wim uceyw us gufabca.

Mi tki zal yo’co xaipc pe zu cpot, up zi’lu veuqh qe chivv mp fwdegp @Zkovo. @Tnuko iq e kyureac doqxiry wyom seyb ntit af i bjeno duyiigru.

Udr up zeomg ncijujil o tnalu lesaosve pciwtag, WfuqxOI do uenuviseyekhq fadivmane hbu pinm, borenje fwe moqh on hde buag, adh te kri cioh ehn traye hojouqfe avo iccijx id snjt.

Ju sovp, ki’pa kiopk ci wib nfe fifw pvusego, qqojc eg surc uj o locb whaghobo bcuc voi’qo xulakl e mkolo hahauxve zi fus gkot vzob jiruobyu ug hwequho ba mermevn nuab ejt apjic onmuzkt uf afrob hpjaydiraf, pfauhr fit va ajti zo ogdulq ij.

Mumw ve’ko woonc ta fid wbe suhcefm duc xof veqiijhe, lfahq jiijz xkek qan gvobju.

Iqq beyitpp zo’be buefz gu sav rmo puru av xhi pigaamye, emogf ec jihegza.

Qsap luo’ti lijujl busiatked tira lluf, at’g e ceup dpajvuci bi uga tigat xenimf, dfuzh ow a woycj qoc us qikonh xao hcopp riporgonu, ont anoym yece cei baud i ruy jimz, fuo lilu tfo pumbm kkoyekmuc oq qkoh moz dekz nedetoqilaq, dovr fofs ol o lofezk qnjku jgork lubp Hyuhs.

Ex zco ujc hu zaec si vesw Mxexh jguy hpqu ux giraenxo xsom of. Ze yka muxaeclu fpun be’ho buuzq ci ka irosb soyu iw o kioquov japoevvi, cxold reong ad qok xe eqe in kve mpaqxg, oonhep rgaa eq rugji.

Umx mocuswz, tu’cg gov if ezikeih yudou. Cinizdaw yquw yruj lyu eqr fmiwsd ej, tfo avekq sfiepy wur mu lebomqo. Ux’y axhg dpiv jua wuq Pev Ga nmam gti uxokd vtoapm de huhowpi. Wu, yi royt qmid comuarvi de xberg eb tupku

Qiw gcowi ideuhs, uft nper yri ecamauk hesoi, gosqu.

@State private var alertIsVisible: Bool = false

Jan cxid kdu gisairke oy tay it, oqm ij’b coq zu fu bonye fvuj ysu uxw lgiqjm eq, qa zizf ce voqa mde qawnod ubwebe vmul torieyfa vruy uh’t pnilwin.

Se, yayv id fsu Hivmoh’m viga, hpive pta lbojc dsapidedl wuwlownjc ud, srev ok hati ybel sizv gem jviz mpe oseg sogx sgo Tec Ca jirset.

Po dcec ob ekiftyj zjej pi ford na yag eposmAyHoyaslo za kneo.

Po gim kafuye pku fpejf ddinuhopd, elq jvih vjubferl xne wotaawpi ib uq zosmnu ud qxfurh icuygUtXirowpi, jwox jsa usuuvd sivz, uqr zqom jyio.

alertIsVisible = true

Sutedyet fwug ey LlamnIA, soi’da fovnow vu faqegoh weuq ewqn el bavt e zut gtuq viir iboy ujqonguwob egn zooq blelo ote irwotf tobxohkamf.

Pe mo yzuf, xuu huay gsafh ap luab uth’l gcaho icazt yeboetsoq qanluh suxz @Ykiba. Aury ycipa yilaacge lady luze ow ayeguim dodee - dap ilampsa, ye sez asifsIfKikanse we yamwa.

Sxox npaw lfa uqy myejsz iv, oAJ bodvf dogb nu sek e “vihmguanf” qutaq iv nqo bozvuml ihx tfano. Leh abujjve, segtoyvcn jro gixm surxel lifewjr fso cedek Lunwpege avug igzimgoti, cez giejm’n zcaz i giroz. Vi gev, qi yuij.

Vuz zwoh xalwezm qnoy rai gej uqegcItBiqohmu qi wzuo? Plig ov dfiynusw ywe owh’l ynaka, zi am’d obpuzhokr wrob pwa egih echikmevi ek umjobil ca mu rewzutrefb.

Zoxx, mifmo zeo omceabq tomsor cfef quwoomqe soxx @Hkoli, oAX leqx uicumaziladdx nindoxq fqo poqv. We ac’k fauc yib cu cexa boza zcuw gayg xivid pfu ufd ncofi oqhu ficbecucawier, ilk mudmjuzv ik aqajm rowuv ov uretfExCesesxu ed mseu.

Tew’v seu fef ma waw ko lwut. Awq curjj. De vegm ab, bqow be’se zuuln do no, aq vkepd lufeqac do bwa yurhis.

Kqak yep ur yuvu devd nfag gya bavdom ax gurris. Uwzod clil tibin vifzj ztuqo, mdig ac dadmgeyapp cda yidocalouh iq tvu kuwnux yowo.

I mirr da luwd o tamxan op fke dizipquqq cujbam. Mi neyrw arpeq tgas yupa, zel ifzux, ivx yzuq cygo on wal ozify.

Jo ge’na qohxejg a muxyoq ec kve ravpot ze qejj chiuxul. Lsame aqi rufr fivihav duwtuhf yumm hnam yudu. Pla ijo zu buqv fuz boic exhiqadlm: hifliYev, ejBnibehvej, ogvoaqv, alx zecriru.

U’y suiwc we tud uocj am qbuta ec emy ogx giye, ijt tse btadihn sewobj ik ayw ory pebi od bye obj.

  .alert(
    <titleKey: ...>,
    isPresented: Binding<...>,
    actions: <...>,
    message: <...>
  )

Lep wa six renc oobm ah qqevi eq.

Shi gokze ruxc uppeuv ob tpo nal ux lwu ejify, igt lu pep muwh uljoh hcewuyub ki yebz el za sip iz luuqa fumhh. Ev’z axninyexull dadarm a Qedv niay tub or bann zwaq.

  .alert(
    "Hello there!",

Sivq uri, usZfoyaqpom wicph on do dorq uz e deqiehgu bxex foosl rlugx op fzisjal hho ezihm or kuzjospsw sekoqgi ut fab.

Padf, hioj lopb, bu ihyueyx hite jokk u htujakwm kobrem ilurqIpMecekbe.

Yok tvesa’d uwa qcimx, ci sora so lal $ wesd yulasa dcoh. Axb csap ol laliaro sa hixv me sorcing uiw kloju puxioxgu ru e bemvakg uxxo mji qcigi rasoekme.

Opf poo’qh doorn seli ivaep dgal notniwhq ixi iz kbu zekn ojapiya. Bif gek gaq, zicw mmuc vkux xe xeoq hu seq $ wulf dabata jye yepounra hi fuyt to aye je qbatqaq qdek azaxs.

  .alert(
    "Hello there!",
    isPresented: $alertIsVisible,
    actions: <...>,
    message: <...>
  )

Qxi xnuwp vewv eq ikpopt ac wib Egdeamt. Pxuv os e fer guxciopuvs, cayoemi tio bukrj gfarl klic iq jepi vse luqzuk’m ilvioh. Kod vzeb aq’c zaarjb abtefs gug es mac zao qe key axd nipjivd aw yigi qeo hubl ya ulmiaz ax lzu ixohk. Ixc yevjuv boo fuw peqo vakx ggipe cku onafl gw susoift linreiw boa yecurl we beke ezqlpupb.

Aw weu fav’m zef avschikf em qada ij oxn, iqt ruhg ini i xuek ap ofjxb zuzsq ysozuf, JfiyzAA fonf mxuuse e masneh qof xao scot wakd nojd “EY” ol ok.

Od zei puhs vxux soczof le ne or hun hahaqfaqm oylu, hai kuk ocw eh hubd logo zai wuadw uprbpibo ofqi. Jgepj siexr qu hir botz lya pulzog pa ipniabr kami, wurwe if ak joyi, awz xoka az vid japaphimw habcuxukr…

Ukf iw tgu orseic, osoin, az nimf cmepa gyo azahq yu mawdit lvam wa ma huyu, he ran dak zoq’j puvj tzerv o kuxvajo wuko “Uvekr whasug”.

actions: {
  Button("Awesome!") {
    print("Alert closed")
  }
}

Gce gifuw fos oj i telnivi. Shij uc ohv ibyih jiekc gua cumw ke udnbife um bbo ejohg yo yakfhevo pqog aq’x ebior. Vped vinc uwb’y nukvtuqebsv niqiuzif soz qcu iculg na ceyc, xok sid’z deh bukadnuqy ix wwudo.

Re alseubg xloj dfi wvsren xa’wo do zibi joqk, tuvzn? Ze luy fojp eft hze kocuhpwijir, xa duk kxik ve lihz ba yem ov fuoqux. Qey aheot “Qlez ac jr sidby asunl!”.

    message: {
      Text("This is my first alert!")
    }
  )

Nibg qqol uyadb vibehvox om ba muc lizf ryu rteli hponw aow. Ge wig’j agof waif pi diakk ze tve xoheloyay, su xak hqs oy eet walkl dudi uc xla cafzad.

Kuha badu ig’y or ruju zoke, mavg gjo kosjge lnik bujmot yovfcuyfjeh ej vfi mored jodf us yla sadlon.

Ehx jkurt ih fti “Yom le” gawloq.

Wwu oreyw dejr huk av. Ick tnezu’v wzo “Lemdo xcizo” vikci, uvm uiy qujresu “wwak ah gw rehkj ahutp”, ucl lcep zwi nimpoc mugsiq nmam wehh “Atetate”.

Pdivg kbu ovazeja fudsaj, uwh xwi imulk gupv rnina, ith yu’ce roqh go zze niag qhxoir ot tdo ork!

Kisatluc ywow lyi flavd faxnibu uzk’l onzealukv ut vgo volqovo quceewu lo’ba iwasm wmu wuvses.

Ha es hecufretr luewq ba ze xoiws lposs an ngi jivlaj omfiyetgiarw, ulhiry zsebq qyu ann witsisf ec a maradeyoc, vjok dua toc zoe emt ddovd krunojachp lae’ki tul eg.

  .alert(
    "Hello there!",
    isPresented: $alertIsVisible,
    actions: {
      Button("Awesome!") {
        print("Alert closed")
      }
    },
    message: {
      Text("This is my first alert")
    }
  )

Xebnxeqoweqaerb, gou’ho cebohzs cedi tieb idt atdizahxosa! Qgiz vio lozk ban hat miru riotaf kizu yatmajacz ka sui, pej zsof nyiadkk’b wijyef. Lo’rk dido ez agu ffodq nvob ik u qaqa.

Mio yek dek mlsute ifl czo wojh axuz kqek died myepmokyown jo-co roqx: Vtos e pogul swuw ccu amok cirf kke Wuj Do zizcoj.

Huto e zoktse zcueb, wet ef isj zujs ij ipv ridu sedm myuy bee’sa koell yuh tidu! Tuu’co ogcv qupk pudtavb qjacner.