API Design in Swift

#WWDCPAD の発表資料です http://connpass.com/event/6877/

Transcript

1. API Design In Swift
   #WWDCPAD
   FUJI Goro (@__gfx__), a software engineer in COOKPAD
   WWDC2014 reports at COOKPAD, 2014/6/20
   

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2. FUJI Goro (@__gfx__)
   • Software engineer @ COOKPAD Inc.
   • Development common libraries for Android / iOS
   

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3. We are hiring!
   https://info.cookpad.com/jobs/
   

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4. Comparison of Swift and Objective-C
   

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5. Swiftݴޠ࢓༷ͷৄࡉʹ͸৮Ε·ͤΜ
   

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6. SwiftͱObjective-Cͷൺֱ
   • ΞΫηε੍ޚ
   • ϝιουݺͼग़͠ߏจ
   • Φʔόʔϩʔυͱ໊લ෇͖Ҿ਺
   • ૯শతϓϩάϥϛϯά
   

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7. ΞΫηε੍ޚ
   • Objective-C͸ެ։ϝιουͷΈϔομϑΝΠϧʹ
   ॻ͘
   • ϑΟʔϧυʹ௚઀ΞΫηε͢Δͷ͸ݪଇېࢭ
   • Swift͸͢΂͕ͯpublicͰϑΟʔϧυΞΫηε΋ࣗ༝
   • ΞΫηείϯτϩʔϧΛ͢Δʹ͸interfaceͱ࣮૷Ϋ
   ϥεΛ෼͚Δ͜ͱͰରԠͰ͖Δ͕࣮૷ίετ͕ߴ͍
   

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8. ϝιουݺͼग़͠ߏจ
   • Objective-C: [[receiver method1] method2]
   • Swift: receiver.method1().method2()
   • ϝιουνΣΠϯ͕΍Γ΍͍͢
   • ࠷ޙͷҾ਺͕ؔ਺ܕͩͱಛघͳߏจ͋Γ
   • “trailing closures”
   • receiver.method() { params-> Type in … }
   

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9. Φʔόʔϩʔυͱ໊લ෇͖Ҿ਺
   • γάωνϟ͕ҧ͑͹ಉ໊͡લͷϝιουΛෳ
   ਺ఆٛͰ͖Δ
   • ύϥϝλͷ਺΍ܕ͕ҧ͑͹OK
   • Ҿ਺ͷܕ͕ҧͬͯ΋OK
   • ໊લ෇͖ΦϓγϣφϧҾ਺΋ఆٛՄೳ
   

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10. ૯শతϓϩάϥϛϯά
    • ܕύϥϝʔλΛͱΔΫϥε΍ϝιουΛఆٛ
    Ͱ͖Δ
    • δΣωϦΫεͱ͔ςϯϓϨʔτͱ͔͍ΘΕ
    Δ΋ͷ
    • ͨͱ͑͹ Array ͸ʮ೚ҙͷܕTͷ഑ྻʯ
    

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11. ͦͷଞ
    • Ϋϥεϝιουʢstatic methodʣ͸ଘࡏ͠ͳ͍
    • ൃදͰ͸ఆٛͰ͖ͳ͍ͱݴͬͯ͠·͍·͕ͨ͠ɺ
    class funcͰఆٛͰ͖·͢ʢthanks to @corosuke_kʣ
    • ԋࢉࢠΦʔόʔϩʔυ͕͋Δ
    • nilΛσϑΥϧτͰڐ༰͠ͳ͍
    • nilڐ༰ܕ͸ T? ͱ T!
    

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12. Swiftʹ͋Δ੍ݶ
    • ϦϑϨΫγϣϯAPI
    • ͦΕΒ͖͠API͸͋ΔͷͰɺਖ਼نϦϦʔε·
    Ͱʹ௥Ճ͞ΕΔՄೳੑ͸͋Γ
    • performSelectorܥͷಈతϝιουݺͼग़͠
    • ObjCʹexportͨ͠Ϋϥεʹରͯ͠ͷΈՄೳ
    

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13. Interoperability of Swift and Objective-C
    

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14. ՝୊
    • Objective-C੡ΞϓϦͰSwift੡ϥΠϒϥϦΛ࢖͑
    Δ͔ɺ࢖͑Δͱͨ͠ΒͲ͏͍͏޻෉͕ඞཁ͔
    • Swift੡ΞϓϦͰObjective-C੡ϥΠϒϥϦΛ࢖͑
    Δ͔ɺ࢖͑Δͱͨ͠ΒͲ͏͍͏޻෉͕ඞཁ͔
    

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15. ૬ޓӡ༻ͷݪଇ
    • Swift͔ΒObjective-Cͷݺͼग़͠: Մೳ
    • Objective-C͔ΒSwiftͷݺͼग़͠: Մೳ
    • ͍ͣΕ΋ઃఆ͕ඞཁ
    • ΠϯλʔϑΣΠε͸100%ޓ׵Ͱ͸ͳ͍
    

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16. Objective-C from Swift
    • Objective-C APIΛSwift͔Β࢖͏ͨΊͷϒϦο
    δ͸Xcode͕ࣗಈతʹੜ੒ͯ͘͠ΕΔ
    • Swift͔Βݟ͑ΔCocoa APIͷ΄ͱΜͲ͸ͦͷ
    ··࢖͏͜ͱ͕Ͱ͖Δ
    • String, Array, Dictionary΋ObjCͦͷ··
    

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17. Blocks
    • ObjCͷblocks΋Swiftͷؔ਺ܕʹͳΔ
    • ϝιου΍ؔ਺ͷ࠷ޙͷҾ਺͕blocksͩͱɺ
    trailing closuresߏจ͕࢖͑Δ
    • RubyͰಋೖ͞Εͯ޿͘஌ΒΕΔΑ͏ʹͳͬ
    ͨϒϩοΫϝιουߏจͱ͓ͳ͡
    

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18. Example
    func dispatch_async(queue: dispatch_queue_t!, block: dispatch_block_t!)
    !
    // trailing closures (຤ඌΫϩʔδϟʣ
    !
    dispatch_async(dispatch_get_main_queue()) {
    NSLog(“foo”)
    }
    !
    // ௨ৗͷߏจͰ΋࢖͑Δ
    !
    dispatch_async(dispatch_get_main_queue(), {
    NSLog("foo")
    })
    !
    

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19. Objective-CͷͨΊͷSwift
    • SwfitͰఆٛͨ͠ΫϥεΛObjective-CͰ࢖͏ͨ
    ΊͷϒϦοδ͸Xcode͕ࣗಈੜ੒͢Δ
    • @objc ΞϊςʔγϣϯΛ͚ͭΔɺ·ͨ͸
    NSObjectΛܧঝͨ͠Ϋϥε͕ࣗಈతʹObjC
    ଆʹexport͞ΕΔ
    

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20. ஫ҙ఺
    • ϝιουͷΦʔόʔϩʔυ΍ԋࢉࢠΦʔόʔ
    ϩʔυͳͲɺObjCͰ࣮ݱͰ͖ͳ͍ػೳ͸ΤΫ
    εϙʔτͰ͖ͳ͍
    • ʮObjCରԠSwiftϥΠϒϥϦʯ͸ಛผͷରԠ͕
    ඞཁͰɺͦΕʹΑͬͯSwiftຊདྷͷύϑΥʔϚ
    ϯεΛൃشͰ͖ͳ͍Մೳੑ͕͋Δ
    

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21. API Design
    

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22. Swift࣌୅ͷAPIઃܭ
    • Swift͸Objective-CΑΓڧྗ͕ͩɺશ໘తʹ
    SwiftʹҠߦ͢Δʹ͸·ͩ਺೥͔͔ΔͩΖ͏
    • ͜Ε͔Βͷ਺೥ॏཁͳͷ͸ɺʮObjective-C͔
    Β࢖͑ΔSwiftϥΠϒϥϦʯ͓ΑͼʮSwiftͰ΋
    ࢖͍΍͍͢Objective-CϥΠϒϥϦʯͩʂ
    

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23. SwiftϥΠϒϥϦΛॻ͘ݪଇ
    • public classΛObjCʹexport͢Δ
    • 3จࣈϓϨϑΟΫε͸ґવͱͯ͠ඞཁͱࢥΘΕΔ
    • export͢ΔclassͰ͸੍ݶ͕͋Δ͜ͱʹ஫ҙ
    • ΦʔόʔϩʔυΛ࢖͑ͳ͍
    • δΣωϦΫεΛ࢖͑ͳ͍
    

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24. Objective-CΛॻ͘ݪଇ
    • มߋ఺͸ͦΕ΄Ͳͳ͍
    • Cocoaࢿ࢈Λͦͷ··͔ͭ͏ͨΊʹ͔ͳΓ޻෉͍ͯ͠Δҹ৅
    • ෳ਺ͷblocksΛड͚औΔͷͰ͸ͳ͘ɺ࠷ޙͷҾ਺ͰҰ͚ͭͩ
    blocksΛड͚औΔΑ͏ʹ͢Δ
    • ެ։APIͰͷϦϑϨΫγϣϯ͸ආ͚Δ
    • ͨͱ͑͹SELΛड͚औͬͯϝιουΛൃߦ͢ΔͷͰ͸ͳ͘ɺ
    blocksΛ࢖͏
    

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25. ஫ҙ
    • ਖ਼ن൛Ͱ͸طଘͷ੍ݶʹ͍ͭͯมߋ͕͋Δͱ
    ࢥΘΕΔͷͰɺಛʹϦϑϨΫγϣϯ΍ϒϦο
    δ·ΘΓ͸ݱࡏͷ࢓༷Λ৴͗͢͡ͳ͍΄͏͕
    Α͍͔΋
    

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26. Show Notes
    • Welcome Swift
    • The Swfit Programming Language
    • Using Swift with Cocoa and Objective-C
    

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27. ͝੩ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠
    

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