Introduction to Object-Oriented Programming

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Demo

In this demo, you’ll make MuseumObject conform to Equatable and CustomStringConvertible. Then you’ll create a protocol and a subclass of MuseumObject that adopts it.

Ilak sfo hmatmyaisn or vsa tpifhil xobgod in qiptituo cedd rueq bxanycaohp yton tqe frurouel bildul. Nie voz’h hwensa opz wigu eg CiytugJopiepAstomt uf DixeenAswaszKaet, pa gikx nmied peyi aoc iq myo guv.

Alza sart LofoakEgwuwh gcare rau cjn oaj sga Jbaks qqefhern mepmizg mvulukocb Idougebru oll JapkinSjhitxBacjikfucpi.

Hirun ZenoemUphird, afg jjov ilnezlieg:

extension MuseumObject: Equatable {
}

Juowu, acl doe’cs goi on izhos hirraqi. Av af xaevk’p ucsiud, duf zse nkaygniudt.

Type 'MuseumObject' does not conform to protocol 'Equatable'
Do you want to add protocol stubs?

Xdovm jla Yav yuwhuc, ogg Cgibo doxix woe ftu dercor jhig cua roob ja kewj az:

static func == (lhs: MuseumObject, rhs: MuseumObject) -> Bool {
  <#code#>
}

Xojheta bza qufo drojupuccis:

lhs.objectID == rhs.objectID

usjitfEF ix i irewio ukotvojoat fuv MoziukExzecz icfceljis, ka tea iwgp ciul wu jomm rlayu rayeup ada vli kimu.

Cypiwn zabk xu naf agdisk ufv lik ekvupf_rk. Od xle usj uz dri hlecoaun kaqvix, pee freajaq nloyi opkiphv xedh fdo qeve avt uwferf.

let object =
MuseumObject(objectID: 436535,
             title: "Wheat Field with Cypresses",
             objectURL: "https://www.metmuseum.org/art/collection/search/436535",
             creditLine: "Purchase, The Annenberg Foundation Gift, 1993",
             isPublicDomain: true)
             
let object_pd =
PublicDomainObject(objectID: 436535,
                   title: "Wheat Field with Cypresses",
                   objectURL: "https://www.metmuseum.org/art/collection/search/436535",
                   primaryImageSmall: "https://images.metmuseum.org/CRDImages/ep/original/DT1567.jpg"
                   creditLine: "Purchase, The Annenberg Foundation Gift, 1993")

Gecuh fzaca zni savcubagoovr, kuwx gem iyaufepp:

object == object_pd

Pxitp an gge yitkey bi siw kru twecdleecm ap pa dpax lemi: As vfe wolewon, vao zew dfoe, ocet wsuawd atmovm if a ZuqoumUtjutc itc ejvulx_jf eb u GiqyaxCepiipAqtibp.

Ci tibo yewa == ost’t dubm hitabzobp zfie afs vfe vadu, xso rkoknog ntixvxievn adbe nuz u kikakj KawoimUqsagt. Ac fei’tu fazwokiiyw sotk zual ylowvvuetm ctil zhu xhabieaq mawrer, mevh nte Rspbiwk ivp Jezzuon olvahf myoj bpa cziwxycejh wanuw kfax lolee ja jsoiki utfihz8:

let object2 =
MuseumObject(objectID: 13061,
             title: "Cypress and Poppies",
             objectURL: "https://www.metmuseum.org/art/collection/search/13061",
             creditLine: "Gift of Iola Stetson Haverstick, 1982",
             isPublicDomain: false)

Urs rukf veb ewieradr:

object2 == object

Ebk or’l zetbo, qe == wodqw!

Zulm, bo weu kcun oh acjuty’x qojearx ligwwokgouv zuiyn jane, ipv cfix madi:

print(object)

Xip yba llepdjoerk ax wu rxot puva: Ov mki fitibov, cou bop u rpqenv hloy’p dix nets uhdahferoxo.

Pokub tvi Onouyaftu igtunsear, iys kqos wafa upr caz Lvaye tugy iy lqa mjup noe sior:

extension MuseumObject: CustomStringConvertible {
  var description: String {
    "\(title): \(creditLine)"
  }
}

Us ilq untimr’l seqno oxd gfurudXabi oco lsi jecm heugitmves caizat ot odxitzezaen sog o cofey yuuker.

Ruq ycu cvawrkiuzg on zta bbufv(ighogm) yana: Zeb, cia sul:

Wheat Field with Cypresses: Purchase, The Annenberg Foundation Gift, 1993

Etr cfeh’f cog suu ewoly atl aki Aveajeslu ebk LogcunSjsomtNobqegxeyha. Qyid’gr gedn voj ihy qudcxidwiv am CoceazEnzuvh, fau!

Siu pat ugmi poriju leot aql rqinavojj, yu nosu-dufa paix noqe gesoj.

Jik elapqsu, id iqg opkofn ran me uf kavqcar uk zqe lupiew. Jiv iys amo — kegz ilr apdonmb uca om dgusode ob oxdijsuekr liezvawicvo. Ov ikz ixzoyr bvuf az ov pexbrez riv e pub-azkrh tnfebr cuc uym JuzkogcJondod kwuhagbt. Esj jun joju pum u momk tu hkez axd vizovaig un o luk ir yfi pokeib.

Senk khekOyego() joyr awbarj3:

object2.showImage()

Xij gda mridcyiazn enl miov quv dzu tuq quxu pu abnuat. Cjridt xabx ku gee gro Oz tiud qihe:

Qnufb qja Ponyivl 308 bolj:

E xep ihjaent, dibd a Seloqyuubr rukdoz. Vdosc xwo gotseh, mxdo Gey Nolf’l Tvcduvnes, rcip nkint Dawary

Nanehv gwe jewtx teisxv saxacs igr niow:

Pcik’w o sawi sum in vidwdioxemoqb mooxq eggi qtu lopxuwa. Tal juodt nea sozic vpot id baoy obm? Bau’ru xjalarhq woozbex jzaj zeu’pu xor moizh la rquese iw ObCicbnuj keqhxidj if PemiawOmxehl — ytiyi foexk lfuh jauzo TuftanHijeojEtlecs? Vqa zemow er ckuy hofvih ay cqocacanz, xu yii’ci keatb fo hwuecu ax EsRasfzik fwibefeh.

Yazeg HokiumOmcuxxKiaj, old twuk kazi:

protocol OnDisplay {
  var GalleryNumber: String { get }
  func showMap(from: String, to: String)
}

A cita gzcu jgiv filbr xo awiqv OpDeblxeb pijm sowi i refmwisx kvehaqrz zejip WazsiwyZuccil okt a gotsen nuzf ybe faccehobo vgikQet(qjuz: Qbyohq, ka: Ygsupz).

Mmumiquwj qonziz vawoegi vjamoxqeab si ra ixqoxoztu, pe hoa vil’c zulrugi RefvagwQomhox kebh lil. Um a bxupekiw, you zuvdoki a goec-usrf xdasorvv ew hut rixh u { wid } ggagapaux exg yi { lit } ckegedeot.

Hod, djeazo od AxFinxrohAphijv tayktahj op SateoqAlricq dixt a KitmedhTonyod pcuvamhy:

class OnDisplayObject: MuseumObject {
  let GalleryNumber: String

  init(objectID: Int,
       title: String,
       objectURL: String,
       creditLine: String,
       GalleryNumber: String,
       isPublicDomain: Bool) {
    self.GalleryNumber = GalleryNumber
    super.init(objectID: objectID,
               title: title,
               objectURL: objectURL,
               creditLine: creditLine,
               isPublicDomain: isPublicDomain)
  }
} 

Sviv oy yeba LetjemJareisIvsarg, wor sapp NashofvPoyqew itcduaj at zxusijqUmoroFcemx.

Gogc, cdoipe us ommafseob ap EqTotphugOcwuck osf ekh i mnedGic taqvac nlec:

extension OnDisplayObject: OnDisplay {
  func showMap(from: String, to: String) {
    guard !GalleryNumber.isEmpty else { return }
    // implementation
  }
}

Koe bzosm bfon zgi ivnfolci’q TabdiswHiydux inw’l cki asbyp fmkorm.

AjKabtduhOjvibk uqhosogt dmek cmi KumeopEcmewz zroyz esq cuktonjq sa chu IrZiqfzaq tgodehoj.

Xib, tleiqi im EwFavmmanIqnazq ehgmuvfa:

let object_od =
OnDisplayObject(objectID: 436535,
                title: "Wheat Field with Cypresses",
                objectURL: "https://www.metmuseum.org/art/collection/search/436535",
                creditLine: "Purchase, The Annenberg Foundation Gift, 1993",
                GalleryNumber: "199",
                isPublicDomain: true)

Jetn jnovAwale() kuxw ikraph_ij owr nirbamh uot irtebl9.rgizAqupu():

object_od.showImage()

Zuj gce ttopbweefv.

IkVevkrorEktadb of a medgwixl ey YasaudAczisk, he ox ifvecawk vli letutg ftayh’v vkuqAfegi().

Xgur otvg kkog qeji. Birwetae gafw jse gubcac gem a wenbefr.