SwiftUIのpropertyWrapperをふんわり理解する

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1. PROPERTY WRAPPER SwiftUIͷproperty wrapperͷ֓ཁΛ;ΜΘΓཧղ͢Δ
2. ɾνʔϜ͕ྲྀಈతʹมԽͯ͠΋ɺٕज़తʹ֤νʔϜʹೃછΈ΍͘͢͢ΔͨΊ ࣮ࢪ͢Δ໨త ɾੵۃతʹٕज़ΛΩϟονΞοϓ͢Δ͜ͱͰϞόΠϧΤϯδχΞશମͷٕज़ͷఈ্͛Λ͢ΔͨΊ ɾqiita౳Λ༻͍ͨ֎෦΁ͷൃ৴Λߦ͏͜ͱͰ৘ใʹ৮ΕͨਓʹδϟϯϘͷΤϯδχΞͱͯ͠ಇ ͘͜ͱʹڵຯΛ࣋ͬͯ΋Β͏Α͏ʹ͢Δ
3. PROPERTY WRAPPER ϓϩύςΟʔϥούʔͱ͸ɺϓϩύςΟʔʹରͯ͠ಛఆͷৼΔ෣͍ ΍ػೳΛఏڙͯ͘͠ΕΔ΋ͷ ϓϩύςΟʔϥούʔͱ͸…
4. ಛఆͷৼΔ෣͍΍ػೳͱ͍͏ͷ͸ओʹϓϩύςΟʔͷঢ়ଶ؅ཧΛߦ͍·͢ ϓϩύςΟʔͷঢ়ଶ؅ཧɹɹ஋Λ؂ࢹ͠ɺมߋ͕૸ͬͨͱ͖ʹࣗಈͰߋ৽͢Δ͜ͱɺ͢ͳΘͪ※σʔλόΠϯσΟϯά PropertyWrapper͕࢖͑Δͱ͍͏ͷ͸σʔλόΠϯσΟϯά͕Ͱ͖ΔΑ͏ʹͳΔ ࠓճઆ໌͢Δ4XJGU6*ͷQSPQFSUZ8SBQQFS͸ @state @Binding ObservableObject @StateObject ※σʔλͱର৅Λ݁ͼ͚ͭɺσʔλ͋Δ͍͸ର৅ͷมߋΛ҉ࣔతʹ΋͏Ұํͷมߋ΁൓ө͢Δ͜ͱ
5. σʔλόΠϯσΟϯάͰ͖ΔͱԿ͕͏Ε͍͠Ͱ͠ΐ͏͔? গ͠࿩୤ઢ͠·͢
6. ࣭໰Ͱ͢ɻ ීஈAPIΛݺΜͰؼ͖ͬͯͨϨεϙϯεΛͲͷΑ͏ʹView΍Presenterʹ౉͍ͯ͠·͔͢?? 1ɼΫϩʔδϟʔΛ༻͍Δ →ɹMuseνʔϜͷΞϓϦ͸݁ߏ͜Εͩͱࢥ͍·͢ʂ 2ɼasync/awaitΛ༻͍Δ →ɹFocaͰ݁ߏΑ͘ݟ·͢ʂ
7. ShionͷsignInPresenterͷ৽نొ࿥ॲཧͰ͢ɻ(৽نొ࿥ϘλϯԡԼޙʹൃՐ͠·͢) Ϋϩʔδϟʔͷωετ͕͔ͳΓਂ͘ͳ͍ͬͯͯಡΈͮΒ͍Ͱ͢
8. ม਺ʹΞΫηε͢Δ͚ͩͰ࠷৽ͷ৘ใΛऔಘͯ͠Viewͷߋ ৽·ͰͰ͖ͨΒศརͰ͸ͳ͍Ͱ͠ΐ͏͔?? SwiftUIͷpropertyWrapper࢖͑͹˞؆୯ʹ࣮૷ೳͰ͢ʂ ※ݫີʹ͸ɺUIKitͰRXSwiftͳͲͷϥΠϒϥϦΛ࢖͑͹ՄೳͰ͢ʂ͔͠͠SwiftUIͰ͸ඪ४૷උͰ͢ʂ
9. ࿩Λ໭͠·͢ʂ
10. ֤छpropertyWrapperΛઆ໌͍͖ͯ͠·͢ʂ ਖ਼௚গ͠ͱ͖ͬͭʹ͍͘಺༰͔ͱࢥ͍·͢ͷͰɺ؆୯ʹઆ໌Ͱ͖ͨΒ͍͍ͳͱࢥ͍·͢ʂ ࿩͢͜ͱ ɾ֤छϓϩύςΟʔϥούʔͷಛ௃ ɾϓϩύςΟʔϥούʔ֤छͷجຊతͳ࢖༻ํ๏ ɾσʔλόΠϯσΟϯάΛ͢Δͱ͖ͷྲྀΕ ࿩͞ͳ͍͜ͱ ɾCombineʹ͍ͭͯ ɾϥΠϒίʔσΟϯάͰઆ໌(΍Γ͔ͨͬͨΜͰ͚͢Ͳࣗ෼ͷٕज़ྗతʹ·ͩݫ͔ͬͨ͠Ͱ͢স)
11. ˏ4UBUF σʔλ͕஋ܕͰɺσʔλΛߋ৽Λ͠ɺσʔλͷൃੜݯ͕Viewࣗ਎ͷ৔߹͸@State͕࢖͑· ͢ɻ ؆୯ʹݴ͏ͱViewͷதͰ஋Λมߋ͢Δ஋ܕͷม਺ʹ͸࢖͑ΔΑʂ
12. @Binding ஋ܕͷσʔλͰɺσʔλΛߋ৽͠·͕͢ɺσʔλͷൃੜݯ͸਌ViewͳͲ֎͔Β౉͞ΕΔ৔ ߹@Binding͕࢖͑·͢ɻ ؆୯ʹݴ͏ͱσʔλ͕֎͔Β౉͞Ε ͍ͯͯ஋ܕ͔ͩΒ@Binding͕࢖͑ Δʂ
13. ࢖͍ํ ૒ํͰঢ়ଶ؅ཧΛߦ͍͍ͨʂͳ@Stateͱ@BindingΛηοτͰ࢖༻͢Δ
14. ࠓ঺հͨ̎ͭ͠͸஋ܕͷQSPQFSUZ8SBQQFSͰ͢ σʔλΦϒδΣΫτΛѻ͏΋ͷ΋༻ҙ͞Ε͍ͯ·͢ʂ σʔλΦϒδΣΫτͱ͸ʁ JamboͰ͍͏ͱ͜ΖͷTimeLineEntityͱ͔?
15. ObservableObject ͜ΕΒͷσʔλΦϒδΣΫτΛ4XJGU6*͕؂ࢹͰ͖ΔΑ͏ʹ͢Δʹ͸ 0CTFSWBCMF0CKFDUϓϩτίϧʹ४ڌ͢Δඞཁ͕͋Γ·͢ɻ σʔλΦϒδΣΫτΛ؂ࢹ͍ͨ͠৔߹͸ɺ0CTFSWBCMF0CKFDUΛ४ڌ͞ ͤͯ؂ࢹର৅ʹˏ1VCMJTIFEΛ͚ͭΔ
16. @StateObject ObservableObjectΛ४ڌͨ͠ClassΛΠϯελϯεԽ͢Δͱ͖ʹ@StateObjectΛ͚ͭΔ incrementCount()Ͱ@Publishedͷcountͷ஋Λߋ৽͍ͯ͠·͢ @StateObjectͰdataSourceͷˏPublishedͷ஋Λ؂ࢹ͍ͯ͠ΔͷͰ… dataSource.Counter΁ͷΞΫηεͰߋ৽͞ΕͨσʔλΛViewʹ ൓ө͢Δ͜ͱ͕Ͱ͖·͢ɻ observableObjectΛ४ڌͨ͠DateSourceΛ@stateObjectΛ͚ͭ ͯΠϯελϯεԽ͠·͢ʂ ButtonΛԡԼͨ͠ͱ͖ʹdateSourceͷincrementCount()ΛݺΜͰ…
17. ·ͱΊ @state @Binding ͸஋ܕʹ࢖༻͠ɺ૒ํͰσʔλΛؔ͢͠Δͱ͖ʹ࢖༻͢Δ ObservableObject @StateObject ͸σʔλΦϒδΣΫτʹ࢖༻͠ɺ૒ํͰσʔλΛؔ͢͠Δͱ͖ʹ࢖༻͢Δ ͬ͘͟Γ͜͜Λཧղͯ͠΋ΒͬͯɺσʔλόΠϯσΟϯά͕؆୯ʹ࣮૷ՄೳʹͳΔͱ͍͏ ͜ͱΛ͍͚֮͑ͯͨͩΕ͹޾͍Ͱ͢ʂ
18. ͋Γ͕ͱ͏͍͟͝·ͨ͠ʂ