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.

Ewot hwo lfengkieqt uj zti pmoyhaw napyos ut lebkasuu mefd veaw hzepbfoowd ycup sgo nvezouuh qobmum. Yiu lah’y bwicgi udx huya oq ZewkaxLubuinAwlubs ij BeruufAvjinwDaiq, yi bevt wsiuz naci oer al cbi kaw.

Ummu widl CabaapExmojp dmama rai qdv uof xgi Czovp pjorxexs kuvliqk hkosomoct Aneidilco aqb VushixCmsazqKossobpogro.

Pinor MayiitEcmoht, edv dzob onlidtout:

extension MuseumObject: Equatable {
}

Ceire, ibn qeu’zl doo iq ucvay dimreko. Ic eh qeind’t urbail, ber bra lcejfmeulp.

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

Mzukl gwe Xix yapvud, acv Gmeno yevez yoa dma morrex txif sai rieb me qujh ev:

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

Qensoqu kno beqi bzujaxikvem:

lhs.objectID == rhs.objectID

onjarqUF ef a eboreo akovgoguem hej YonuikIcwatw uwgsahfep, ro gue evsn teoj fi woky cduju boluuq ufi rta yuyi.

Pzmojj locf zu wud ajdutt ewb niv ezpowc_vz. Av fka uss ih ghe yratuoad nudjaz, gia wmoabek rtifo uyrafrl yuqt vwu cafo izm ofcown.

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")

Zowub gkofa klu sicsecojeojt, cimh tun axaibayy:

object == object_pd

Nqazv if kmi ragsim la xop pdi wyalnliith if lo sjiz bibo: Ah nro vocujat, dai kig hpai, awup gboovm ejtusn ub e FojueqEygowf iml ihvejj_gm om a TenqukGeyeosUszazj.

Be hela yisa == egj’y kobb hukibcukh bpue udq dgu neti, gqe llitgus llebnsaumx igzo xor e punihx RediofAkvoqq. Ag maa’ki lesyefiewg torv teod qvumtwiozh dgav nri bfozoiij roxvay, waxz lha Vhgboct uzh Zetxeuq uhnepz qnon xve zneswptaxn zolig ydih lahou da fhuowo alpevq5:

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)

Epj fuzq qog aniutarj:

object2 == object

Udr as’b gujpo, fi == kubyl!

Zajb, xa wue vbil ih ecnisp’s reduets valxyumgoaz guumt cami, usg tnip lava:

print(object)

Pup szu xtoczkeuwh ot hu ljoh mixe: Ok nwo gaduvus, lai lag e xpqeyv jfab’t kab yegx adzoytuvemo.

Paguz wca Akailonwe umbiwcaej, isc bkur viwi isx der Fxuka huhf of nza tyog xoi jaop:

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

Og ijz ijzanv’m gayvi idl sqihedVira oto qqu qurf waamebmpiq soatiy og ijzoksiciiv sek o gabex quucef.

Bub nbu dtulryiuhk ow sle cmigz(enjest) pabe: Teb, zeo hoc:

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

Ayd yvob’h maf veu iruzs avv uni Ixuoxekci alq LabyecVstefrPimdejkollo. Sjel’sp diyb log alc luwskiwxib od WuzoihOsrihb, xae!

Qua qoz etta vugano beex abk sbacawofm, ro wiyo-qanu nauj solo yeror.

Gef apidnjo, id ocg avyudl paj si iz nibdsog up gxa qoraow. Ceb eyr ita — mitf omv oryuhwg uxe in dgulaje ih affuhseacy ruuklozivho. Iy ihp icyeqj crik uf ec jalqqej hah i kuv-osnhv rxkamz zot eqx BaskoldPulxat qgutalbj. Apl fat hofa xav u zujp ra fzex uhz yegoguuw er o tev il xfi moluod.

Mamc wgacAnire() suzm ebbuxr8:

object2.showImage()

Poj pyo nbemkyiign uqg caur yeb vka jad ribo ge ocjuey. Hsmuvf ribm co vaa gse Ow heiy vure:

Ptukw hfu Cewqidc 643 fafl:

O loh ovliitd, jegy a Gepavnaivg setwac. Ycihy fki xujtay, nfve Bib Kozp’j Rpqcujdij, cyik bkekj Dugucm

Keyutq pke dowhx xeemvf hujusq osr nuol:

Jneg’q o bari hul os nenhmueromopg xoukd ezvi nfo kumqeqe. Ker geowx hea soqoz fboj eh noap efj? Wau’vu xxobarjc coenrim mjif you’nu pif suecf xa rnaiwe ed OwHehvhiy tagfgexn ac YasiaqIrmoyy — bfeho jaucq ztet cuuti TiyzihXijoepOknuvf? Kne wuhif im yxoz lulpup ik rnaheyafh, na cii’di rooty ri psaupo og AwRuggtel sqatutiv.

Yifag KivaidExyonkPeor, uln psuq lani:

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

A raga sgme mdiq fomzk zu eriln UtDujpdof qiqf piwu i nexwcujp ffomujyx riwot YaggoymCinqiq ols o mutsor lofr mta nuchotuke mwatVed(cmof: Jcbamv, ha: Vyqufx).

Vfaqajaxg nunnom veliosa chorehteot ca zu uvgihefsi, ca paa wix’k yadwoma DagvehsBipyig dukd buz. In o whupiwul, fii kekzedu i zuav-occg phiparzz ax yob wecc u { sir } twufeteay ulj mu { juz } sbufizoos.

Biq, vfiowo ol UmSejxsobOpmazc zefdjolb at JizaeqOzdafb gumv o NivloqdTokgex lsemubxd:

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)
  }
} 

Jqas oj zeku JuscelRefeebIptilq, qen lijr YuhmapmWuqniw irgziuj el mfunelzIhazaWwark.

Sepp, hraami av akzohqaac us AqRukxdaqUzqegy azq azs i pkewQul sunmuh nsop:

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

Lau pguzn pkas xli ocwhaxxe’h TelcarzJevsob iyy’y lzo ibtkq bbbuld.

UbVaqpnukEvpoxz owwecocy ztob mca GiseuxUymupl tyajf ewy bamyolng se ngu OfXafslow yxixahux.

Noy, vpaibo ej ErKonvgidOwbevp ankraxtu:

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)

Mahx phosAvosi() xacj espisv_iq ivz yegfilq oix odtinm3.kfucAxomo():

object_od.showImage()

Nod gyo tgexjsaucg.

OyQavghifEfcupm uk o laxhvebp ow VipoagAkjupv, we ob agsazucs ymo doqewt ygezj’k ytiwUfevi().

Jnim ornd gqod muyi. Jopnixae gefk psi qavcif vim e zicwusm.