今日こそ理解するHot変換@社内RxSwift勉強会

今日こそ理解するHot変換

Transcript

1. ࠓ೔ͦ͜ཧղ͢Δ
   Hotม׵
   @ࣾ಺RxSwiftษڧձ
   

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2. https://speakerdeck.com/ukitaka/cold-at-she-nei-rxswiftmian-qiang-hui
   લճͷଓ͖
   

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3. Hotม׵
   

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4. Cold → Hot
   

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5. (෮श)Hotʹؔ࿈͢ΔΦϖϨʔλ
   Hotʹؔ࿈͢ΔΦϖϨʔλ͸ҎԼͷΈɻ
   ͜ΕΒ͕ಛʹݺ͹Εͯͳ͚Ε͹Hotʹม׵͞ΕΔ͜ͱ΋ͳ͍ɻ
   • multicast / publish
   • replay / replayAll
   • connect / refCount
   • share / shareReplay
   • shareReplayLatestWhileConnected
   

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6. ·͊ͱΓ͋͑ͣ࢖ͬͯΈΔ͔
   

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7. publish()
   

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8. Question1
   ͳΜͱදࣔ͞ΕΔͰ͠ΐ͏ʁ
   

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10. ͜Μͳͷ؆୯͡ΌΜʂ
    1,2,3Ͱ͠ΐʂ
    

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11. ͜Μͳͷ؆୯͡ΌΜ
    Sequence Map Hot
    subscribe
    Քಇ
    

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12. ͜Μͳͷ؆୯͡ΌΜ
    Sequence Map Hot
    subscribe
    Քಇ
    

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13. Answer
    ਖ਼ղ͸…
    

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14. A. ͳʹ΋දࣔ͞Εͳ͍
    

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15. !?
    

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16. (෮श)Hotʹؔ࿈͢ΔΦϖϨʔλ
    Hotʹؔ࿈͢ΔΦϖϨʔλ͸ҎԼͷΈɻ
    ͜ΕΒ͕ಛʹݺ͹Εͯͳ͚Ε͹Hotʹม׵͞ΕΔ͜ͱ΋ͳ͍ɻ
    • multicast / publish
    • replay / replayAll
    • connect / refCount
    • share / shareReplay
    • shareReplayLatestWhileConnected
    ؚΈͷ͋Δݴ͍ํ
    

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17. Hotม׵ ϙΠϯτͦͷ1
    ConnectableObservable
    

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18. ͭ͡͸publish()ͷฦΓ஋…
    

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19. ConnectableObservable
    • connect() ϝιουΛ࣋ͭ
    • connect() ΛݺͿ͜ͱͰHotʹม׵׬ྃ͢Δ
    • connect() ΛݺͿ·ͰObserver͕͍Α͏͕͍
    ·͍͕ಈ࡞͠ͳ͍
    

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20. ConnectableObservable
    

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21. ͳΜͰඞཁͳͷʁ
    • ྫ͑͹ɺෳ਺ͷobserver͕Hotม׵͞Εͨετ
    ϦʔϜͷ஋Λ࠷ॳ͔ΒͪΌΜͱड͚औΓ͍ͨ
    ࣌ɻconnect()ΛݺͿ·Ͱಈ࡞͠ͳ͍ͷͰɺͦ
    ͷؒʹશͯͷobserverΛsubscribe͓ͤͯ͘͞
    ͜ͱ͕Ͱ͖Δɻ
    

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22. ͳΜͰඞཁͳͷʁ
    (ConnectableObservable͕ແ͍ͱͲ͏ͳΔ͔͸ߟ͑ͯΈ͍ͯͩ͘͞)
    

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23. ConnectableObservableΛฦ͢Operator
    • multicast()
    • publish()
    • replay(bufferSize:)
    • replayAll()
    

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24. multicast()
    • ͦ΋ͦ΋Hotม׵ͱ͸ɺ಺෦తʹSubjectΛར
    ༻͍ͯ͠Δ͚ͩͰ͋Δɻ
    • multicast()͸SubjectΛࢦఆͯͦ͜͠ͰҰ୴Π
    ϕϯτΛड͚ΔΑ͏ʹ͢ΔOperator
    

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25. multicast()
    

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26. publish()
    • PublishSubjectʹmulticast͢Δ
    

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27. • ReplaySubjectʹmulticast͢Δ
    replay(bufferSize:) / replayAll()
    

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28. ConnectableObservable·ͱΊ
    • ColdͳObservableʹରͯ͠ɺmulticast() /
    publish() / replay(bufferSize:) / replayAll() Λݺͼ
    ग़͢͜ͱͰ ConnectableObservableʹม׵Ͱ͖
    Δɻ
    • ConnectableObservableʹରͯ͠connect()Λݺͼ
    ग़͢͜ͱͰHotͳObservableʹม׵͕׬ྃ͢Δɻ
    

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29. ࣍΁…
    

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30. ConnectableObservable
    ཧղͨ͠
    

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31. ଞͷHotؔ࿈ͷOperator͸ʁ
    

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32. (෮श)Hotʹؔ࿈͢ΔΦϖϨʔλ
    Hotʹؔ࿈͢ΔΦϖϨʔλ͸ҎԼͷΈɻ
    ͜ΕΒ͕ಛʹݺ͹Εͯͳ͚Ε͹Hotʹม׵͞ΕΔ͜ͱ΋ͳ͍ɻ
    • multicast / publish
    • replay / replayAll
    • connect / refCount
    • share / shareReplay
    • shareReplayLatestWhileConnected
    

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33. ͱΓ͋͑ͣshare()Ͱ΋
    ࢖ͬͯΈΔ͔
    

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34. share()
    ConnectableObservable͡Όͳͯ͘
    ObservableͰฦ͖ͬͯͯΔ͠
    ͖ͬͱHot΍Ζʂʂʂ
    

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35. Question2
    ͳΜͱදࣔ͞ΕΔͰ͠ΐ͏ʁ
    

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37. Answer
    ਖ਼ղ͸…
    

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38. A. ͳʹ΋දࣔ͞Εͳ͍
    

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39. ƅЧƅ)Űō?
    

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40. Hotม׵ ϙΠϯτͦͷ2
    ۂऀ: RefCount
    

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41. share()
    

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42. refCount()
    • refCount() ͸ ConnectableObservableʹର͠
    ͯݺ΂Δ΋͏ҰͭͷOperatorͰ͋Δɻ
    

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43. refCount()
    • Hotͷ֓೦Λ෴͢ΊΜͲ͍͘͞ศརͳ΍ͭ
    • Hotͷੑ࣭ͱͯ͠ʮsubscribe͠ͳͯ͘΋ಈ࡞
    ͢Δʯͱ͍͏ͷ͕͋Δ͕ɺrefCount͕ڬ·Δ
    ͱʮHot͕ͩɺ࠷ॳʹsubscribe͞ΕΔ·Ͱಈ
    ࡞͠ͳ͍ʯΈ͍ͨͳڍಈʹͳΔɻ
    

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44. refCount()
    • ࡞Γ͸୯७Ͱɺ࠷ॳʹsubscribe͞Εͨ࣌఺Ͱ
    ಺෦తʹconnect()ΛݺͿɻ
    

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45. Question3
    ͳΜͱදࣔ͞ΕΔͰ͠ΐ͏ʁ
    

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47. Answer
    ਖ਼ղ͸…
    

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48. A. 1,2,3
    

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49. ͪΌΜͱHotม׵͞Εͯͨ
    (ͳΜͰʁʂͱࢥͬͨํ͸લճͷεϥΠυ΋ΈͯΈ·͠ΐ͏)
    

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50. ࢒ΓͷOperator
    

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51. shareReplay(bufferSize:)
    • ໊લͷ௨Γɺshare + replay
    • share = publish + refCount
    • shareReplay = publish + refCount + replay
    • ʮHot͕ͩɺ࠷ॳʹsubscribe͞ΕΔ·Ͱಈ࡞͠ͳ
    ͍ʯΛकΓͭͭࢦఆ͞Εͨݸ਺͚ͩ஋Λreplay͢
    Δ
    

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52. shareReplay(bufferSize:)
    • ࣮͸ΊͬͪΌॏཁͰɺRxSwiftͷExampleͰ΋Α͘ʢʁʣ࢖
    ΘΕ͍ͯΔɻ
    • ม਺తʹѻ͍ͭͭɺ࠶ܭࢉͤ͞ͳ͍Α͏ʹ͢Δͱ͖ʹ
    shareReplay(1)Λ͚ͭΔͱΑ͍ (͜Εʹ͍ͭͯ͸ผ్ൃද͠
    ·͢ɻ)
    • RxSwift v2.5.0࣌఺Ͱ͸shareReplayʹ1Ҏ֎Λ౉͢ͱ࠶ܭࢉ
    ͕૸Δόάʁ࢓༷ʁ͕͋Δɻshare΋ಉ༷ͷݱ৅༗Γɻ
    

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53. shareReplayLatestWhileConnected()
    • ໊લ͕ΊͬͪΌ௕͍
    • ͜Μͳͷ࢖͏ػձ͋Δͷʁͱࢥ͏͔΋͠Εͳ͍͕ɺ
    RxSwift(RxCocoa)Ͱఏڙ͞Ε͍ͯΔ Driver͸σϑΥϧτͰ͜Εͱಉ
    ͡ڍಈΛ͢ΔɻͳͷͰڍಈ͸ཧղ͓ͯ͘͠΂͖ɻ
    • ShareReplay1 ͱͷҧ͍͸ɺconnect தͰͳ͍ͱ࠷ޙͷ஋͕औΕͳ͍
    ͜ͱɻͭ·Γ1౓ .Completed ͕ྲྀΕͨΒͦͷ͋ͱʹ͸replay͞Ε
    ͣɺ.Completed ͔͠ྲྀΕͯ͜ͳ͍ɻ
    • ڍಈͷৄࡉͳྫ͸Driverͷͱ͖ʹઆ໌͢ΔͷͰ͜͜Ͱ͸ׂѪɻ
    

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54. Hotม׵·ͱΊ
    Hotʹม׵͢Δʹ͸
    • ConnectableObservableʹม׵ޙɺconnect()
    ΛݺͿ
    • RefCountʹରͯ͠1ͭҎ্subscribeΛߦ͏
    

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55. Ҏ্ʂʂ
    

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