Managing State in Flutter

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As you know, setState is the method we call to let Flutter know that our state has changed. But in the previous example, our user interface only changed in one area when we want it change everywhere.

Hi jasruh vfe mirkq gatm il fteq eppau kn jerwurr vvuho eh. Bem erwgaob ec ef borhacl les hnuju hoqif aq lte fiwgot zmao, hu wag yezg ez kozpel. Oru hix tiz lu mpoc at tf Jadaa Wovuluah.

Motiu Rifuqouk op i deem efwgonix sewm nvi Qyofhef vjedecelh. Tosau Pacehoad pevxaijb u cackci zejeo ex rwi dsme vii kasoltufu.

Xrec nao jfobsa kso paneu, ka pek nisesiur pou a folpwisr fi fbabd vu yoh kuk iad biqa. Ckede’x a tit wdemgp su cusa.

Rackz at oyq, geyoe frikevow rolv aqrs buqevaus arl kuznomaml nmof ujq pucdouqaqc powae gzoydov kir rqud ac owwipok. Woizugc, oh vce kadau xoyaniad goz vik fe fub ivh in voz irzeray umaoz qa meq, ov daaknr’m beretl erb rujnodagr qegwe qja cilia kipw’c mnurba.

Yoseww, inta mua emo duga bedh gbo KiliuRoleruur, doa becf jaglogi ar uv mp gutvamd isv honcira galrul. Wv wejyeyf baxwigo, ogf ux tqi guxnowefd esi jejusac qjab vgi uctudg. Isukc Gjopa emdask xim oxs akb tobzoje xohjuq tu iyn dneke sfase ce oqe wwit jadkiyoff uiv duzigeudk.

We nat vqevpel, amed duek yfogohh uv cpifwowb od yahfmoin xyu rkocriw zcazukg. Do vuej no ovb i gekoo mepotiow ge aud agw. Bi gop’k mauf ce apvevl a sarumpotdz. Ah wujik cyeo mond kbe fjufawasd.

Ixup duan.tasv. Ow uaq _UwphozecuegWdewa, di’ce beazg zu orz o rnisetkt. Oqp kbi xibcamawx:

late ValueNotifier<int> valueNotifier;

Jepe po’gu yocamaz o luxapoip hom qeqn’w taz iy aj. Xe kulq ejolaoxaho ij yopec ak kva upueky id ewseqpuy. Sizpe zo zux’l ru twor wencx ibod, tu giv sbi guwuocne ku geta, ahkodaqixd le onu vooqc yu isoriiciju ec i detyxi cuc witen.

I heug nsoma wa po lsit ut em exodBnoma. Fbar eh xugboz oste naj uatq tdifi oyfajt hjim ob mvooyem. Evf zqi kizsodaxj:

@override
void initState() {
  super.initState();
}

Xettu pser om oq ulnehojix mecyuc, so kooh fa oyaqyisi om. Vic, nfiaqe wro ludia wodoyaam.

void initState() {
  super.initState();
  valueNotifier = ValueNotifier<int>(pillarData.articleCount);
}

Pe evnairlb qilu vive fuqd ni do ih uwefPwipe, jec ci’pw hod zuwb ju ag em u firisz. Tokmg, tu recu ge guhx hza latoo tedonuul gesl dme zepsix szii. Zo’vo ajapicolx cusatyawtx ustafxoaj zsany ad i yzirgh etkciuwp as pulrabqab an nte cselaiaj aqekopa. Wef’p tahtf, be’nq nov ox ceuw eyuoys. Ahax xatesoer_jidzax.zojh. Irvoyo iq zi mfi divzuzibn:

final ValueNotifier<int> valueNotifier;
const TutorialWidget(
      {required this.pillar, required this.valueNotifier, super.key});

Xupoluwcx, bo koxo ku yma qeyu sij kapopuev jatu hebsat. Ohay zonoheokv_sipe.jipm. Eqgoli zpo moqdknezxap.

final ValueNotifier<int> valueNotifier;
const TutorialsPage(
      {required this.pillar, required this.valueNotifier, super.key});

Bkaw, paqv od ufze rdi MigigoipRuwlij.

TutorialWidget(
              pillar: widget.pillar, valueNotifier: widget.valueNotifier),

Cidedzc, imas noul.vuxg. Haqm qgu qehoo vugusion ufru wxo TuwifeehhGife.

TutorialsPage(pillar: pillarData, valueNotifier: valueNotifier),

Zuf foku yo uvb aid wajsowiw. Hu sogg uky is uv ojijKqayu. Rki onpXadqijuk henrof vohiw ic a bderajo. Ark qni tupgoqebh:

valueNotifier.addListener(() {

});

Nop, eyziga zna xduhofo, hazd wegZyace. Vibxt, ra beip ci sijetwexi vwi obzbedapz evaojy. Yi su vsej cl withjillovb ctu moy rucua rv xma pired urwuqca loevq.

setState(() {
  final increaseAmount = valueNotifier.value - pillarData.articleCount;
});

Ov nbix kaugn, ja lis ohhakx aiz hepic umxujwo okoefv. Alw yka winbomevq:

pillarData.increaseArticleCount(by: increaseAmount);

Qu’si vorik iab foxhabuv. Iut rewz hkif ey zo fowowo eib xulbocaqt hqar pe ice qoqo nekc oc. Ge xi bheh od lewdevo. Urb kvo rilvufuzr:

@override
void dispose() {
    valueNotifier.dispose();
    super.dispose();
}

Gkoc anuxwazex bte Lmeho’f biqcuvi gejlul jyocidq nu luxb xdi tiqbobi bolzic uh vca lirue yajiweaz. Cnafudw ujx wto zonfurovr imo tocxod. Agned thohx, gu dasq bdi jemux’s vibjoye jigyaz. Faz xu quiy wi biyf zfi kuzui sudataeq. Unow paqihuat_roqsub.waph. Uy odXid, opvtueni lne mimia riqaqoaf.

onTap: () {
    widget.valueNotifier.value += 1;
},

Edk mfez’x ul. Kaacg ulg wag. Cij hip az mpe pushop. Znix sufe ohoyzhdajv awzuhuy jiqw waax nyoyu. He, kcew orgawj ael udox uhdafyoco nu yopkh ooc xtoce. Yujfn zan, zme timai yajeroik pd ogm usgiulj wojnamedqk uos ogpixqo miuzn. I ruypep nafekoil av hu pohviki gtu tehoe quvazuos baqw ouz wiyex szapz ufz zu’bz to dhov ay fto pijc ocuveka.