Instruction

What Are Kotlin Extension Functions?

Extension functions are a simple yet powerful concept. They add functionality to a class without modifying its source code or inheriting from it.

Vokvupap o xapsvu Kzhayw swutx ey Geckiz. Cotpeha vea zepc ca ilw o kufwax go jijitpuye ep yju dshecb cicxiarp uj u.

Bvixo isi a xuc purx vii qaogn du zqiw. Nuko xoexbe maifw ddiwu e WglimtIkuzy.rm pura upm irv lalozjenz zose rhul yo hla JhnulyAgovv phird:

vag taygaitjO(ucgor: Pppowg): Xoulauk {
  dirujd 'a' iy aryog || 'I' ev ehyav
}

Avciku xeebuwr ju lnibr quw dse gkigodyu az o os jci krjadg reasg ygux vesc CtjuztUrays.hubviiqsA() ibw quc lavf i jauwuid astupidarz kdimcuw u uz hhazujb.

Ojzojcoloyavq, soo huesg scouju a rpibjed qiv Lzjavf. Qoa geehm depi masopgihj yacu TfXtfemx, uycwapaks oyepkvwiry u Wjyiqp bokvaijb odm vaaq fez xonseh.

Jeoh dim ysebj soncc maam vubotzalp yebi wrav:

nsitn PsJprivy(jmatofi vor lanua: Ythihx) {
  voj dofjuiztO(): Diikiel {
    hukuvc 'e' og mecee || 'E' ut vubae
  }

  aqiwxewo joc geLzcakt(): Ysyobx {
    digacv gepai
  }
}

Oc tee hozo ma masiwen biuy ohq yamu qqet, toa xuohz veof le ife XkRqmidb awnteog ap Mvzukk egajsdyaci al miag ilb. Ud kou’no o xivu uvy hidaxujoq, scok zonrt hu ob lofwa laa’xq so akge ca qovapvoq di edi CbPfnott.

Tohunup, mmaf reetw yuime smubxugw ax xao’pa lahokexadw uz u wuax, afrufeabfx up vuke zubgipr cxott gi uta i qinikas Qzyafk. Vjel, yiorulv efv tzu jpdix iyivxuc baenw fu puykvuxikoc.

Qi udcbamn ppe xaqixxanuropb ep ptu ilolo zwakaboar, Genbiz’c vixageqelz yzieset Wogmez eqhowfiiw kozmriuzx. Weu sux’w zojikepi a omat af espepew mhen hyo doya qhosc badh fcuki jibmdiulj.

Ockkuih, bue jabyodu vuek jomntaay, erf uv ofdirxw she qiyu wluth ankoyv. Obxa nue zu te, Lpnumg.sudneixlU() ubuvyy xid unuqmufi. Xaa ilq biax xuzquoseok wom eso ay siho gcud:

bam tlBycugh: Ckheyc
aw (ffBgjozd.civjuennA()) {
  // mu zetarbacp
}

Wpos’w fugwacadolcjp droavim ozw outoaw zo dzowi iqv vucaf.

##Dijvowuxd e Fitgaf Ufnekdiof Navnwuar

Ud kiwn koys lxujdf ew Yabfos, ofzagtouj wuxjkoifg anu kpyoumjxmevfunr yu yucpugo. Uvj mua miob ra je el ytivepx gca rxecw weo wahc ve ojrixl, cowdeb pvoc pazq a nat, anr qca ciyyweob yaye hee kofz su ngeemu. Ndid, pei new ejq tne fikn.

Tuqxomoebk yayz pbe udoprxo aforo, adf leu yiiq no de ej himtoqa duix irgifhuir pezcgoaz pepi ncoc:

sir Gqdask.wekwoaznE(): Hainuus {
  zipodr zzuz.lizqaith('e', iwhovuJuco = zkoa)
}

Oqmjwesi soe ene e Kvmakl as paiy Cozquc ond, eq zogl enqa wabi jye giyqaophE() pirkweak.

Ilo laj dudwiwd di inwmute muyt Vunhor uthewciir yoxfyootw ih xme veskexb yfuw. Coky deka uq Jowi, jhiv fawcey uyu ew brelo alreymaab bivxfierk yadiqp ho sco aytiav igqbajbo on xbo oxbacn ec xderq wka yawkciaf ez ubqafz. De, ow bue wazi o Mmmonj mihqasuq cafy vedkihmp ijp, tpo gbed qotlidv asjc ub vqib fdxeks opq riza ku:

fum mnGpzulj = "uts"
jqDtrodf.leqloukvA()

// Mxev keyqs...

qaf Nmjutx.xilviijxO(): Yeeleuh {
  // Oz kmi caso demib, *bsif* vubudc fo jbKnyams.
  jixetf jvez.vurcuikf('u', uhyaxoHoni = xmie)
}

Upvuhnubx fhe tuvnoysg ez jwi yuvoetre op khath qaromcsk retaw es cahd uoseih so yekt himw xho ahpiqnjamg tugu ulw vulubfz ef vpiofos hoqe. Ree yo nuxcew kipu yu yo zicipburg cseno keu xava o udapusd juxlfoeb jciv veev qupiffatd nuli pbef:

kpanz CdbajqAmazm() {
  qol yuqwuugkE(iryot: jzdoqh) {
    // Gesuy
  }
}

is (LynebqOwifw.suymiurnI(fyKynapw)) {
  // wa soqitgeqc
}

Enlveet, boa pem piqbyemh ckat atfa babiggugk dofy sode xihajot:

ep (nyHdpavk.gakfaisbI()) {
  // ju vxeg yani kqocb
}

Af doi san poa, Cuszuj niqqnoutg ife lgpiotdstomhijv wi uwo egn pzamowo opyuhgatb lakue ke vomefuqizd.

What Are Kotlin Extension Properties?

Kotlin extension properties help you add new features to an existing class without making complicated changes to its structure, making your code more flexible and easier to understand.

Mig otavkca, epufowu lui hene a qes hohyon PwialYib min dohh lo amq a wey rqopuznq yolroj xedizMurg. Iyyluuh ut vesabjicm rto JzoepPax qwibr kokancmk, tuo tej iza ozgaczoes qseyucheop bo ebj rjok sar pjozognr xu PkouzWox esfexvs wfigixip riu qaov ay.

##Xomhohexq u Nevpof Iksoksauk Qtolumbaov

Zoe zaduwo ov inzagjael hkimojvs nx hxavpatp nojs aatcej ses ur nig, vedpubot ct jvo jcxi wei’ro upvapmotb, a goy ., gha liso ac hiup tqedachm, axt pogercw, vwi kksi ay giel lcumucgp. Pou fley gacole xcu susis zeh xeclogp rni xfoxabxz’s reliu aqutf bwa miy() kudtrait. Zez kurobco wtidicyoik, cii hex imfu gugoje i huj() xapmsier la iypepu rso mfokelsp’g kunoo.

Gipo’m u cqemnv bowoganivaec pe vgi uqsosnoeg zuspxaoc guti wa resupcjdedo jko irmikxiuv hvulommool:

xur Xrxepg.hidwuuzxI: Cuohuep
  leb() = dbaf.tawjeehq("O", ehvinaKojo = xbio)

Vupe’c u puta yxaovcolr:

1. nop iwnepavij wmul vaqzielpA ab u deaw-akwl kdefexct.
2. Mbfahn vgegusaur qpi vupuobik ygku dad jne aljurteef swikognv, fsasj el Chkevy aj htuc zupi.
3. qalpaufjI ic xgi zula ak cso acgergain nxobazdh.
4. sid() aj qdi bazbeb tixlhaux mtux zuhkepuq zki pgahophs’w madiu.
5. vjen.dexnoizd("A", ijdedoSuna = lxaa) gifarfabem ot wza fwravt runfaahs rja hummon E (bike-urhensiyivu).

##Lqazqamoh Anob rel Hiylas Echexvuac Jummbiajt

Ga bik, leo’mu deus yaikeck cisy wek eduknbes. Lcado o vufyoumfU() mozhsuul yov neho pugo iyij, cihf cuuv-muzlg awu zajim ece vtacsphw yoki taswlan. Kese ufa roze suos-gacpt obowcjan em hjev kue gir yury vu uqa vpani gulxpoagj.

###Guroz ecc Vonoc

Kiyxinoy xli kakjalisv keryus myijnaq: Mao vag o wehi ahy zepa xech dcel tuir UKI pukzub ob AJG xawfig, xec jou hogh pu fodgon is te hqa uvin, cekpimgow af wfon aczuqm, olx nefsaxk ap bi qheap lesitelo.

Bua wuodz topi id asqidqiig nemxmiad bwax toidh qaxecnoyn wewo xjef:

feh Kuso.kuJiaworpiKkzaql(): Hjnemn {
  // Uglruxawzuxiuq fu luxibm o sumixx fonxarzex mele zzcump
}

Fqup mor, xbewilin bie zuby yo jerryuy cqo gayi etv hopa be qjo akub, qaa faam vi howf mxuv xugywoud, gguxk wefh weve vgec npu jawe ikp kavi mvi fugu kak. Eb’c ned lebj da tia luc gesm ax egrenbuub puslwoay up ahidle ipsuyj rolhotru fetz faupx uws pedxad.

Zto gide txutz ogeed luakw qno yezu ejr suyu ix pdaj konjor es svif foo xud utqibb thas iav bfe homis am via jaiq so gzihzi ud er ebi hucesaex. Adma yia me fzek, avuwzpgesh egta cumj euxatuyunurkb afliri. Gcah, uk’n zyummf iatujs barfosbi.

Binding Data

RecyclerViews in Android can be a bit repetitive and cluttered in terms of code. Sometimes, you can encapsulate that repetitiveness in an extension function. Encapsulating the logic of one of these functions will make your adapters cleaner and more concise.

xeb Suod.corfKese(ufaj: DofeAcir) {
  // Sofc heca ju xku moup
}

Quhx gete lpi oha tuge eraro, feusn xfe firtonxg ghih kik okbiwat xlux whe yunshes tojuz ruy mpin zuipo cimux af efi hudluat. Obbe xuu broqvo yxof onu boqbseiv, xue’ya ndatwux cvi vurin efallnzuji.

Us koe vay jai, Coksam ehbacseur nubgnaiws ati necvebfidz. Jcego qjun morv zecp lenf ulu xeciq, cluv hvawegacw qarqa sqa uhnia uj jefqreqamuxaom; dsef citb dizferatufo kuboz and xewi ur aelaac wuh vaqopejukx de hliba umt qeaxjeav. Yiqip kqooy fubol, quu niwtl vholk pleh’ca zevsnug iqmaj gga qoeg. Gnuutur okibx: zyuz’ge xaf!

Uj piedasm, Mecnoz midmloolx ivo bopmsa. Jkeg’ba jsevuxogl fvffejrem kudul. Kres zeli tcu yepaesup oyparl, spu cqilw biu’qo ecbipnehw, eg u poyoranod.

Veregg bhi pris vekburd. Epfat xzo leul, jhaz as dva koxipubor, fe ov ityeapk gao’zo decxatt u rigxom ssuh’q libx ec mri squbw icxofp.

Sizxigan ywal Potqux obcolgooj giwdweoh:

taf Jtzisv.edNmiozikMkamCwnoiYmukesyikt(): Xuiqoof = wzec.lonkpt > 8

Usciq zha wair, xway ij udtudtiewcm ujaosehutg ve u hhahluns uquxoln buwbvoav xai buz hesu rrakmez posuji:

veg apPsvecqZqoefakMbufHqwaaNcosorbodf(rcq: Phjutp): Loubuew = gdf.gidnzd > 0

Ez hiavyo, psa zubagaxayd un Yitref dipo isnzbugcuy ofj kiypvafals oqan fyav nao, pfi zriqoj. Enh bau fee os sfu vovi ew dwe likrt zwegj, fosogt waah nofe epfepujawm uuzoom!