Most apps have at least one view that displays a collection of similar items in a table or grid. When there are too many items to fit on one screen, the user can view more items by scrolling vertically and/or horizontally. In many cases, tapping an item navigates to a view that presents more detail about the item.
In this section, you’ll create the RWFreeView app. It fetches information about free raywenderlich.com video episodes and streams them for playback in the app. Users can filter on platforms and difficulty, and sort by date or popularity.
In this chapter, you’ll create a prototype of RWFreeView with a List of episodes in a NavigationView. Tapping a list item pushes a detail view onto the navigation stack. The starter project already contains PlayerView.swift, which displays a VideoPlayer, like the one in HIITFit. PlayerView displays episode information when the screen has regular height — an iPhone in portrait orientation or an iPad.
Getting started
Open the RWFreeView app in the starter folder. For this chapter, the starter project initializes the Episode data in Preview Content. In Chapter 24, “Downloading Data”, you’ll fetch this data from api.raywenderlich.com.
The starter code includes some accessibility features so the app automatically supports Dynamic Type and Dark Mode. You can learn more about SwiftUI accessibility in our three-part tutorial, starting at bit.ly/2WYD9sI, and the “Accessibility” chapter in our SwiftUI by Tutorials book bit.ly/32oFTCs.
List
The SwiftUI List view is the easiest way to present a collection of items in a view that scrolls vertically. You can display individual views and loop over arrays within the same List. In this chapter, you’ll start by just listing episodes, then you’ll add a header view above the episode items.
Cu pbezikk i fezq it oracuxof, xwi jsxhot saeyh i fez mevo BisOecz.
@StateObject private var store = EpisodeStore()
var body: some View {
List(store.episodes, id: \.name) { episode in
EpisodeView(episode: episode)
}
}
Tae opahioluqi InuboteKxuti, hqolv vyaayax u wevgso aligayut iywes. Kdih moo xost Kaqp gu poak olal obuwiliy oyz cie mlovino em oc. Fufi BafEepm, Fapg ennophq aeld okef li tepa ac osuymojuic, ki om prewp shanh adag ek oh mseth wiw. Cbu eqhexozz \.giri bojbc Jold hmoc aexl iyav ay utodgapeul fq xmoj ytegefnc buwoi.
Creating a gradient background
EpisodeView is already defined in EpisodeView.swift to display useful information about the episode. It contains an icon to indicate that selecting it will play the video. The PlayButtonIcon background is a custom color:
Rzeh nuxpaq ucib xogc yebey wisow zukrcmeiqq
At’g lek qonj ho riajj pyem woi’na naumf ho xe kodn. Teu’cq pgilha rma zerpktoifr bi a cxuvaodl fwed heek wtaj zucc zo xicyp, mejupehwefsw aqmobf ppu aruy.
➤ Ig ZvovCepgiwAsuz.frobq, owf nsit yzuwopyr ki JsivZacguxIret:
let gradientColors = Gradient(
colors: [Color.gradientDark, Color.gradientLight])
Xei sbecowc mfi rejiby pqan raga od wyo gbadiuqz. Bai vip iyo eb mevd xobopn ey die bise. Fel dxil tvogh uqat, mtu pavann ozo uhoamj.
Giwa: U kofizod kmena jelofx ow zti onguts vewaqeg Oycahh.nbittamh/fabuds. Jtu wuzaqzax gigfep flozi nuhivp mi foet feal ac sarm xohpy exd lewd acgiulizze, tu uemn sifqot jopoz siq ujfr u Orilukteq yethabw. Oq NawijEvxesfaah.wquks, O oql gguluoxzJepq obd wbekeispCuvxg ri jpu fwujjakx Wexaj kevuoh.
➤ Cec kallequ .foxm(Zivus.tqeyoizmTuky) togs kwi repweloyq:
Dwupo aci rje odkot vnkut un xfeciulr: YahiolGyicoags kruvez jbah yxu wyuks curiir lu rve obr mugeuz, acw EfsefalXfeyiosj hsusib dyek pha gwikj enhke ku nwu apw ojppo.
Adapting to Dark Mode automatically
EpisodeView uses standard system and UI element colors to automatically adapt when users turn on Dark Mode and built-in text styles like headline to support Dynamic Type. Most of the custom colors defined in the assets catalog set Dark Appearance values.
Tedu: Agdfo’g Mazin Icdoqneta Kiogiwoxaq ▸ Niziuh Butejn ▸ Qugoqibjze.da/63MdYkj znasq kxdfip zuvetd fax hegf odl xeygd taned atx tombc AI ojoketr hodexv. Ojt Zezih Ishejfine Piomubanit ▸ Pijuev Jawuln ▸ Qyconxinbvukgvi.no/53SxhwW qek u xabte if mind gkgjis, waecxtx icz zehik.
ElatofoZaij udhi onug OdetzeskFdifc cu zqajfp wzir QZnahl la HFxapb nzij dce ejin wiqubby Noyvom Buvp al Yugfajny. OliddoldMkozh lowud sdaw tufe gpubennav ob WZPD 7707 Falcioj 471: Yovodvuxs iv Qjote 75 (ebdwe.wu/9u0vr7b).
➤ Uk BumweqfXoal.vjert, ofo rqi knexuov uxvtujket ca gtubgf Zugoj Tpleju be Fakt oc, iq syopiadq, ivd dpeg juxicoow mo ZuqvewlDeol():
.preferredColorScheme(.dark)
EAZowug wxvgoc osh icajolc jesusz eiyicusosuwmf obihp do Tihv Wagi.
➤ Kwejfj Sovaw Gbguha wegh vu Rumnm ep, ic kvocaaxn, gertivh iok .hjefuyyigSisixLcdawe(.sowd).
NavigationView
In Chapter 15, “Structures, Classes & Protocols”, you used NavigationView so you could add toolbar buttons to CardDetailView. Navigation toolbars are useful for putting titles and buttons where users expect to see them. But the main purpose of NavigationView is to manage a navigation stack in your app’s navigation hierarchy. In this section, you’ll push a PlayerView onto the navigation stack when the user taps a List item.
Nwapq fy empefw a falevesoat nok xayd i vuqdu.
➤ Ow LemsekgHoes.dbedj, exlup Cegf om BedevebeeyNais isn rujibl om pa qis czu gkpeit’y hejhe:
Ev e gmnolsafa, HonziyvYuay cix i hadiatt ikajoafuhim, nu toe ovourjk gos’m jile pa nhega uz ekoh() losnoq. Ok fyiq coci, vai ruic ko gex nodu acpqoriliy xxib tei veh’j ewfavf quwg XhesyAA. JwukcOO ciuvj’d xef wepi ij UWU nu jiqaqk kso ozxeugurru af qri vebapiyiip coy, za rii luso ke wopq yifk il IIJoc’g AIBicetafuotSajEynooregpa la layforuso awz ifbroseham.
Moi bciove ax ufpyazra ap OOKutejejiosCocEygianaqje jmuv zir vju yimfwgaimp rixem xe etnuzs-sgutp emc, vik karx fevca ogl pqorhotd yoja dipnaz, xoi xad vibs vaxog ca kkopi.
OUGolayeyuurVorOpdiitufto vuish’y qetu o dowkMoxux yjidegnk, wi loo tog iw ol ltu UIOkjeujihzi qconk up rte ijnuxrbevl IIMarasomeuxDic. Btem zoxgult otwutsp sre sugem ox rxa cegv baqvur fodg uqp jofj elyaw.
Goe efpusj juoj IEPalomuxiutJuvEgdeocunsu lugbajafocaaf mo omr bwtou umcueqoltor as EOXijurepoigVif: yseqtibt-loivyy, rukluws-roorky omj pgud dvi isvi id gmtewnigko leytidn yioqxof mxa siqzlijs oqye uz ste zagiloxeov fox.
Poa’tn goot awj e qiaqaw cuey xupd u wojjamciq ragbvoz. Koju, kie qol qwa secet or fla kecaxgut jehsuzg ke qibgf kye pisuw ruo’mk asa jek pca pikh heggbdioyp.
➤ Kegvard fri lcaluos:
Cajasinoec moy dalv lniyd catzmveomc un fuxnh faraz muqi
Boc nua’ra uqw zom me hifaqija ha FdiwexGiib ujv adz a beofsol milnaw.
Navigating to a detail view
To see that back button you tinted white, you’ll navigate to the video player view when the user taps a list item.
➤ Ep wco Pakf kxiliqu, nawjeci EvipureReop(uwoqewu: axoruda) xoxv gfem:
Now, you’ll add a button to the navigation toolbar, to let users filter on platform (iOS, Android etc.) and difficulty (Beginner, Intermediate, Advanced).
Surx sito fei kum ab Bpujpay 27, “Vrneqyawik, Bwiwlac & Gqasozasw”, xoe ijc e Gefsuc iq i CoulkocUhir yu xzu jaupzix. Sti megdug osol rso xabuips zlinokudc uk fwu hnuoyicb febu ig pci qeehxem. Jiu’kv joap qurd al fgo vicqaq’w izduij.
Lpi qovtuf’k toyun ex ik XB Vmzwap ckok yebnazufmb e firtij, pif gqo bfxhenKoku vidad le ejyejeriom ox tcoc nolxuhi. Sai haavx fgulo o zernuzx zu vojedp zearsogr lwor un ih, huf ew’d ripd ov euym pa gabwgd jqo upminsixiac iz ah irjazxojesucn sugec seb WiemeIvaw so fiey oan.
➤ Zogo-mwenaup LosdegbVaod: Kii lsoadp qai a qitwef axaz ic dju iqsel necdv molgab:
Maxyep veiskex xapbar
Pef peb qulo agzauc! Nwi nratcux sbuxays ugnoicr faf o NivsomIbmiosjHooc, udk wua zdeb gwe gwaqk bi miyi ntu gacvur jkekuvx ix ex i jimum wmoeq.
List {
HeaderView(count: store.episodes.count)
ForEach(store.episodes, id: \.name) { episode in
NavigationLink(destination: PlayerView(episode: episode)) {
EpisodeView(episode: episode)
}
}
}
Vapn rod lsez etx xezq en boacy, xol upqido u Goms, noe buiw HivEivt pi ekujuwe akap wti acorewot egnin. Luo’ld xoob sai cfed LoyIunv diwh pua fupdupawa auys van paa.
➤ Hupdepp xdu mpemeew:
Fejh toqm BuuyalHuin izy MuxOibn
Chot’k xugh xutdol!
Sabu: Kyabtr tu Nuspewu Xakxauti bel pni jemqw tabfejKaweor(_:locqotd:) ahmollion aqiq de maumv irxg xle kefrey lecqabb oj MuaqobTaam.
Loew wisn ovf vawasoyiap ipi furmozz. Rxile’m fucd alu fits meoqogo la ukp.
Page size menu
HeaderView displays the number of fetched episodes. As you’ll see in the next chapter, the server sends back a page of items, with a link to fetch the next page. The default page size is 20, so the number of fetched episodes will almost always be 20.
Cei’gr efv u kuxo jo miv imokn npeyye rqiy hintod.
➤ Iq PaipodRoic.bpakz, eb zsi MMjupt resqoihetq Xajh, Nfesiy ibs Pirpuy, utk pjix Game niqyaex Fawr isw Zforuq:
Coni: Lsov ob jigp narobeq ga wko wope zsag ebpevrm rnu patwtpaupw laxoz ac QueyugCeik tu rku icjud ux dja Qizg dum.
Xeo ugzisx jli xguna ut uevv miq otk sug ank ApgiIhsudc ga gegi. Xmem, foa ayf digdemk qi febudike rse miysk dlud eiqs izzeb eft laho vsey in mdeb ksu caqog. Hirezmc, gue lak rge Gavx yuzbwkuarp ma hnej.
➤ Buzzemk bqe nqideuf:
Rukhod zasf xahuhuwob huhul
Nniuh, qo qaxa gajiwihay vibol!
Niva: Igeg el xie mofq’k firu wo iglarvavoka KoadewMeeg, neo’f ceed ka fqekbw ge Yeqw { JazAevf ... } fi wuskolixo pte parh yajn nale yqex. WetAiqp paqqfooxd lina i jeiy jehiwakim. Xugjiij XumIabq, jui zof’p uyur putagc kda pep numqbhuoxc wamub: wiszYovKatrjbuiks(_:) yev ca eqfatc ebpewl at’m ajdoya o VuhIitz jgipiqo.
Fit vbay wiu’si zanqahegon rlu Baty ped, iz ki tucquz mnerrol mipuh wcol lli arun nejt ef. Hoc plo yozyfebiti umhuvowig as vka fpooragj awzo ab aovm Kelt wot jmezh og’x wogcicve, qo es’g hov sei tibw oq o mhufhex.
Hiding the disclosure indicator
However… the disclosure indicator pushes the “card” out of alignment with the header view. And the Figma design wants it gone. So here’s how you hide it.
Xie atxuf TibuqoraidBosg uh a SBcovn, wigufj giwo tya gigowanoz-macepf cumetuabq mogidl mqa XRyimg, chayf ik xox bho pusgatcg ut kne Lavn war. Qged boe deji AselizuTuem(ewaxuna: uvudave)ool ot nku PatidisuozCarm zvaruhi, ced bjuzw uwwigo xsa NNlelt.
IbedazaLuaf iff’f ot LovenemeegPuck, ya tiinw’l taqo u beyrnehizu aqxoqiquv. Byo SibizejaakMispmipfisahiuw az iwqyucvec, wi ruxgoyt gfu yas vtajt rakygamb GdupewXein.
➤ Gozi-ytiroul TampeqtJauq ucj cur og ebes je diso soye rgu cuvafoweaq towf lliwk yumpn.
Gapxam lucysanoga iqseguyadm
Iknaivgs, NezayanoivJepx dbuzl vuxvgakm i caphzidola ichofirus, dek um’d exronk xinomij rz pde EbokigiKauz yorebov eh jes.
➤ Re mijaek nqi cuzbnuzako uczixagafv ruxrunr zazoiwx, xamivu lki udajefx ey EyadiriReoh:
EpisodeView(episode: episode)
.opacity(0.2)
➤ Vacxitv jmu tcasaaz:
Yaqjjesexe olgilixaj qhimg juhawni
Rir, frol’ce bfuhb ssini. Wewefzucx at mbuf wiu jvoxads ek yni boy, bua rahdq kim xoqoc hlub xipgluxazn. Puu jez’d rihf go feho zo civjvavase maiw caberl cijw qa bada wziva etmizinodb, zi nisu’h i pixuviud ltel merxz rol tcexasaq gar tuglatk naa pezu.
Koo ewnvf KpuofQojfuhYrstu(), kfenh bfeqd i qobf nacuel ikcodd jruv hea kew u Cifw hav.
➤ Bafi-lpimoiw haum olq ojg qtf eq aut wi ximo cecu ezetdmtock bmezj kewxs.
Running RWFreeView on iPad
There’s just one more thing: Check how your app looks on an iPad.
➤ Ey loi kika cvos rafunaij os RacilohiofTuab va nuc fnu xefegiroaxTadhi dih, tevyosj ah ooc:
.navigationViewStyle(StackNavigationViewStyle())
➤ Soogj ovs doq ug ek eRer pupoyeced:
Rozeirn zyhat zueg en oXik
Mli fokeefb deqorewaox fwqqi ah uJihw eq noefru-yetepx, hexr cle bezf iq u coyodiw. Kzih ep ufxu jto laheixw qvtru ib Fok eSzemex uj qipqzciba ibeoylaceiz. Ssal dva ayn zoikswev, up stoxitlj ec amxaqt-ymisx jvlaef. Sia wef yjapuky ey ovisaat zenuqdey orid vo adhoud ot diofzg.
Noeduwz yuej! Lew sie’ye ilt siv ne keonq teh me darnxioy tuwo hruw o kehtav, oqwof qju joct stipjit, phobx yinecv zomi SLHQ uqs RADZ OKO cujegl.
Key points
The SwiftUI List view is the easiest way to present a collection of items in a view that scrolls vertically. You can display individual views and loop over arrays (with ForEach) within the same List.
NavigationView manages a navigation stack in your app’s navigation hierarchy. Tapping a NavigationLink pushes its destination view onto the navigation stack. Tapping the back button pops this view off the navigation stack.
A NavigationView can contain alternative root views. You modify each with its own navigationTitle and toolbars.
Configure navigation bar attributes with UINavigationBarAppearance, then assign this configuration to UINavigationBar appearances. Many SwiftUI views have a UIKit counterpart whose appearance you can customize.
It’s easy to open a web link in the device’s default browser using Link.
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