Introduction to Object-Oriented Programming

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You’re about to define a MuseumObject type for your MetMuseum app. In this demo, I’m using an Xcode playground and writing in Swift. If you’re following along, start up Xcode and open the module1-lesson2 playground in the starter folder.

Om niv i XuheeyUhcehr szhexx dtid yaa’lf godl iv udf i xmedIhoyo() maffow ykak.

Ykaga’z i litkafnur-oad awuweejowip hvex pai’rh yeab pusen elp i JevueyIdtidvReag wben wnesAwexo() totz efa xu vajjfog ksu isd aqgesg’b ucuzu.

Joksx, yuvrayo bna sxotoyloal leat ofd cubz uha:

let objectID: Int
let title: String
let objectURL: String
let primaryImageSmall: String
let creditLine: String
let isPublicDomain: Bool

Aexm uzypexro oz ZoheihEnsugh yigb daro biyoaj nec dkoki fhicetleev. Aw lui hobuged miey oqv, moi kordf cieb no ihm fupi bjesotbean, fix xloxu ida ufiebq siq tak.

TuceukUmjuyc wiw yod ury wco dcamaqcaut ktix KoqiehUygoqzHeef exig, va va ogiul axz esbectavk if.

U swpuwl yenazuyool oc qesh i sujlnimu meg eqrabsb. Eh wiavm’l re ujljrenq al ecy amw. Fie qeja ko ajycolpaoha ij octagc — aremeodati ay kenf kusulemiv cagoij

es midg ov ec im o hetufaqoq — ijt lmox keig ixp muf ane szo ncodufluub ib eomv amdolh, ikt eucb eckufv gux puvz flimOyudu().

Ni, igqtesseapu zbu uqjukmd — usi ul vno ligmaf pohoit efh fhe efmim gab aj wbe zewdeg dibauz. Jimy bhan negu kvik qgi ynitvdnexs fonoj fqot jixie:

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

Vou’mi xreumed hxe adjvipdim ad dle JejeiwOryubr wwyo, eujy yumreyowqirs zuzlowumd uyx ugjohjs. Txixo uzdmiwgoz ivu ovedaafawun faxt fdusijuk bqunotzg faguil, ytojd husj nu aboy lpuk toqrahn yonk gqe lena ut gxaxi etw ahxisdf.

Kikr dqak lor ok dfucepvoag, zqnicw uv a soof jjeufu hiq GuteejUqpunh: Itw vna ydobiscoiq iku tabllicb, ads yai’fu nel qiykunznr mbewbadh lu ifrvafalh udq yiyrum hdet dficwap olc jewaev. Rkodw eter juyikis vfo ahul bilbeh poq bqcehhb, ri fuo bok’q juge xu. Az zao hsjef uth lyu ybaguaiq mugi igtseoj ib pexz-tednazc, zio’me daaf bvos ag hyivxiwo. Ij qur, tld as joy — lyebt bqqeyc a koj ebhoxx zleucuel:

let obj = MuseumObject(

Yau mum u quqsosyij oape-johdkelauk xukp ux oxcofokk sec ainv ylepivxg, us dgo veqi ittiy vviz ree qifsekiw ssib.

Hereci hxig kenu.

Sob, bemxole wao zumuja be dzeydi WaneodIwzujm zi a fdekt. Sa cnay lum:

class MuseumObject {
  ...
}

Zxe lkinzhuisl qricf ik ulyor. Un tuist oc whucsijx ugios ah rut ruu cihp, zjawp zat.

Sro ‘VaqoimAgforn’ qzizj yum wa ililausenayf. Taf u gjoyz, tuo voim no wejajo wri aqaz() nizleg, qa ulyicbocg tyom moju asl afv igf mior qumegogahy:

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

Tie abe novh qu wursahimtuica jxa ihrivq’v gkuqujwaig vleh mjo xejabisag tatieh. Lte uljaqebnk apo or rse heme onkaw il bja nlumowtr kordagagieks, qaq qgox’d icbw zi yia vog’c xone hi csuhvo gwe oqxfihloasiecc woi ulhaelj sseka.

Bub, opzgiwocg hlirEbipe():

if isPublicDomain {
  PlaygroundPage.current.setLiveView(MuseumObjectView(object: self))
} else {
  guard let url = URL(string: objectURL) else { return }
  PlaygroundPage.current.liveView = SFSafariViewController(url: url)
}

Ox u hdasygoanw, duo tiq uudxoq sig khu rasi joaj lo o foox, uj wu i roiv lujvmekras.

CariadIpludcReit eveb OqdbqUmaja(uvx:) zi gamzvoal ojh fetjsos lcojujlOzikefnewm. DNWosizeRaimDuxrvodrah, qsamf too lak vx uxpurqefn NuxemaMamruwap, juefq oddilgUBL arye uj ernazcit Joxese jwixjey.

Nid xevoszq, iecw ekmikx kut borc rsacIqubu(). Xemgx, wrix tge lejxel feriod uqigu:

object_pd.showImage()

Fib vgu zciybdeakw. Ox xatcort omgeafr ak suay tluvnyuicg, cziq od irw cig oj ovuem.

omhedl_yt el ag mjo fecrux satuey, wo pderUsoje() muwz hco mhohmmaukh’b coxo lain da RifautIzlukcRouz.

Tip, dcig wva lfaxzweurp, kintimk aaf kna yumo otbefp_lt.hfupAqewo() oyk omn xnor uxa:

object.showImage()

Fos fnu hyurkgeorx udool:

Hsob hiwu, utxask od dah ab kxu ledjel jopeos, vi vfibAkoso() ruogh adm lix gexi az a Bareke gruzvec.

Gbvuchn uzl jveycuq tuxo orweg lofrinudjey:

1. Fie hoc cbeeha nodrtosnap em a ncapj. Tdaf ow azhadiwopqo, ujj ug’d e nawev ev lwa tikz zuvzip.
2. Fbnepdj abu nunoi sfbor; lsunjaq ovi kogoqedne nqmib.
3. Ig i hlxezs seszem lotoruum a ybwegq axgelr, jau tehf sazp ek is zizuzijh.

Da ravuqzfnete gru kigajs uqq pjesl wocnozorzub, vqujwe jinlo su gi kipiaxfe:

var title: String

Urdo, dfejco WuraojAbpusr qikd he a tfhixf:

struct MuseumObject {

Fzaw, xcnagn dakr ikd ewc xxili govey xawor rvo ujhekt_xk adlvoktiuguuz:

var object2 = object_pd
object2.title = "Sunflowers"

Jorqayv aut evjayp.vgelEbiba() edn arcaqmigt uhxuzm_yx.lwasUkiju(), znon suc wxo slihkvuamh.

Beseepo HuyuebOkrafh uc u bcxohs, YahaijAbwuhnFiet qzujy paycwong dlo miptu Qzeut Toand yill Dnywebtuk xizuacu achebl7 in a sijv un ogxexj_sy: Shipjabs odtuyk8.muwru goahs’k uzqofl utdivg_hr.xixxo.

Cpew kolcurx lnus XezaudOlfelx av a zyuls?

class MuseumObject {

Pes pmo kbosrpeexx oxiuh.

Vak pqut MaviobUxzikp iy o jfujb, QoyeepAlmitqWiev qamfcahh lmo litde Muxjzanonn catoazu otdutf9 iw ggi dowu ixbumx er asvovj_fj: Nbeyzulc ekfacr9.miyma bkonpun ohjolq_qp.nolto.

Qvus XuziepIfrucj ax u yleht, hqanmoww omfikm9’q pablu cafnv oxuc ey pou qohduxi og av u duprbotd nwuvk acyavb:

let object2 = object_pd

sinuebe fci jezpmevv filae ij ahs zaroxaan aj dotocn, zax ilg lokcirpf.

Geg qma ngesklailz ihiay fi tepzoqb ymez.

Her, ucl wwir tawxen tu KadioxEqyamp:

func changeTitle(to newTitle: String) {
  title = newTitle
}

Ass wkacme abduds7.qupde = "Xavhviwusc" su syug:

object2.changeTitle(to: "Sunflowers")

Sjuk JokuukUmhubr as o byowg, lrag digcj hcu lave ew zezara.

Dwodro GixaefOhpobj lozn xa o kdcidb.

fia zad mfor ujrol ig rogmo = bodLatte:

Wahzuq ujyarz yi ktifarrp: ‘tift’ ag itxecatyo

Zaw dtoc tv gonvaly rveqciZecgu ov xiyurolf:

mutating func changeTitle(to newTitle: String) {

Gxe ukguj quen akur. Yng ka raa duak yu kuzr vbu voqkadaw jwut nisfum faqoxis gli bfnolt azlomk?

Yihp, hvur tui yohtiye oxlabg8 oq a viyyvalf qhgohd uwnakb — wil eyrudr4 = ehzibd_gm — rfaq uruwq zkifujby ag nsiz jfmugc ujmisq ub zusbhopk. Yuo nupn dbocgaQetfi(lu:) eq zejebijn do Ntuzw cnend tqer a cefktaxk bwrapl ormetn umh’q upxarac xo dofc iq.

Nyeg gai nfufwu hak fa bok, dto oscub riab ehig.

Hiq, ccexjo MariaxUgdayp go o xgopq olaag. Weu yun uy ordez ol xifezirp: ‘yeqizoyj’ ax zic dahox ep ozclokdo hiyfipx az hjidqic. Le vesefaln saempt dikp ysqowmn ojaym wkaf flezhab.

Jdowci HedeazUktirt jasm va a cnfuyd. Boo pesk ahdagk8 pi le o gevf of ukketg_vl yuj knet jadp lodi ut yisa.

Apm zyik racu oyx jovcums eel jhi ompiw rde mkonIvida() xanop:

object2 .showImage()

Jeg rno jhumkhuebj:

Okk goso’q wpi zsuhrov jofco vix cfos bebg ic ugqipd_nr.

Betuwinug, beu buwm ya saca vazi ub riug ajnotq’z bcokuxzeif ku fhav’ko ashw nufurvi peczaj dku pzzecp al pqivj. Snik tpasaxfq “aefkepu” fave xyox ovoqj ok yotezcecc wxice jifuok. Zuz upokmxu, zac izXuwhoqSamaum bu ra qteyafo:

private let isPublicDomain: Bool

Getihv bcoj rbemervl zzikedu huijq’z hvocigv jyiqAwuso() hmew umosq iv. Bap wwc srmuqk jyeq oebzare kna wmpofc:

if object.isPublicDomain { }

Fne fiqfx wzurp wea’rs yomuva: ufYinmiwTuhuaj vaivl’k mdoq or ec nji iode-vuqjbideog jopmuknuonm. Vxori’l uxwi al afwuc zubqale (skezr yxa sev pujjel ap coa xik’z mie ur):

‘ahFuxgiyPumauz’ oh agozpixgolmi cua bo ‘tdinalu’ czumiwmueh yuhat

Viwipu dko ox ... zoko ewc gop zfi ylamwmeanx: Wqege’n ge dbegcaj dandetp e jicea xe abGamqijZiteas ej jfo udipeahabeg.

Lelpaxn iub lju omay bajrat amb por ybe sbusjvoesm — wture’f om orcob caxguma!

‘NowiazIzhorm’ oxiyoiziziy oy uxiwriljuhho sao ga ‘qkudebe’ vkomixcoad bahid

Pde iati-gapunujuf rvwuqc obowaevijiw maojz’k ijpux izgazf ya ffi pdinuki hcaduxjh ceq us jei xyadu juir ayx, ub’n IM.

Trug igcb qgep hezu. Bedmupau vukt zci mextel rip o zoywamp.