Slide 1

Slide 1 text

© DeNA Co., Ltd. +BWB͔Β,PUMJOʹ
 ͞Βʹ,PUMJOΒ͘͠ॻ͖׵͑Δ͜ͱͰ
 ίʔυ͕ϦϑΝΫλ͞Ε͍ͯͬͨ࿩ 1 2019 / 09 / 09 Kotlin Fest Reject Conference 2019 Minami Baba
 DeNA Co., Ltd.

Slide 2

Slide 2 text

© DeNA Co., Ltd. ࣗݾ঺հ 2 • അ৔ೆ࣮ • DeNA / ϔϧεέΞࣄۀ • ʮา͍͓ͯτΫʯ • AndroidΞϓϦ։ൃ • @minami1389

Slide 3

Slide 3 text

© DeNA Co., Ltd. Google I/O 2019ʹͯᶃ • Kotlin͸Android։ൃʹ͓͚Δਪ঑ݴޠʹ • ʮ৽نϓϩδΣΫτͰ͸KotlinͰ։ൃΛ࢝ΊΔ΂͖ʯ 3 ࢀরɿh5ps://www.youtube.com/watch?v=ldM6QZy9e0s

Slide 4

Slide 4 text

© DeNA Co., Ltd. Google I/O 2019ʹͯᶄ • ʮطଘϓϩδΣΫτΛKotlinʹҠߦ͢Δ͔Ͳ͏͔͸
 ϓϩδΣΫτͱνʔϜͷঢ়گʹΑͬͯߟ͑Α͏ʯ 4 ࢀরɿh5ps://www.youtube.com/watch?v=ldM6QZy9e0s

Slide 5

Slide 5 text

© DeNA Co., Ltd. ʮา͍͓ͯτΫʯͰͷ࢖༻ݴޠͷي੻ 5 2016/04 ϦϦʔεɹ 2019/09 ݱࡏ 2018/07 KotlinҠߦ։࢝ Java:Kotlin = 100:0 Java:Kotlin = 50:50

Slide 6

Slide 6 text

© DeNA Co., Ltd. KotlinҠߦͷ͖͔͚ͬ 6 ʮKotlin΁Ҡߦͯ͠ΈΑ͏͔ͳʯ ʮίʔυΛͳΜ͔ϦϑΝΫλ͍ͨ͠ʯ

Slide 7

Slide 7 text

© DeNA Co., Ltd. ݱࡏͷײ૝ Java͔ΒKotlin΁ॻ͖׵͑ͯຊ౰ʹྑ͔ͬͨʂ ʰͳΜ͔ϦϑΝΫλ͍ͨ͠ʱͱ͍͏ͱ͖ʹ
 Kotlin΁ͷҠߦ͸ྑ͍બ୒ࢶͷҰͭͰ͢ ͦͷཧ༝͸ɾɾɾ ᶃ࢝ΊΔϋʔυϧ͕௿͍ ᶄ͔ͬ͠ΓޮՌΛಘΒΕΔ 7

Slide 8

Slide 8 text

© DeNA Co., Ltd. ࢝ΊΔϋʔυϧ͕ ௿͍ͬͯຊ౰ʁ ʢ4ͭͷෆ҆ʹ͓౴͑͠·͢ʣ 8

Slide 9

Slide 9 text

© DeNA Co., Ltd. ࢝ΊΔϋʔυϧ͕௿͍ͬͯຊ౰ʁᶃ ᶃJavaϑΝΠϧͨ͘͞Μ͋ΔͷͰ
 ɹશ෦ॻ͖׵͑ΔͳΜͯͦΜͳ࣌ؒऔΕͳ͍… → JavaͱKotlin͕ڞଘ͍ͯ͠Δঢ়ଶͰ΋ΞϓϦ͸ಈ͖·͢ 9 ᶄԿඦߦ΋͋ΔϑΝΠϧΛ1ߦͣͭॻ͖׵͑Δͷେมͦ͏… → Android Studio ͷࣗಈม׵ػೳΛ࢖͏͜ͱ͕Ͱ͖·͢


Slide 10

Slide 10 text

© DeNA Co., Ltd. ࢝ΊΔϋʔυϧ͕௿͍ͬͯຊ౰ʁᶄ ᶅ୯७ͳม׵͚ͩͩͱޮՌͳͦ͞͏ͩ͠·ͣ͸
 ɹKotlinΛ͔ͬ͠Γษڧ͠ͳ͍ͱ… → ୯७ͳม׵͚ͩͰ΋ޮՌ͸͋Γ·͢ʂ
 
 10 ᶆKotlinΒ͍࣮͠૷ͬͯͳ͔ͳ͔೉ͦ͠͏… → ؆୯ʹಋೖ͍͚ͯ͠Δػೳ΋͋Γ·͢ʂ
 
 


Slide 11

Slide 11 text

© DeNA Co., Ltd. ୯७ͳม׵Ͱ΋ ޮՌ͕ಘΒΕΔͬͯຊ౰ʁ ʢ۩ମྫΛ1͚ͭͩ͝঺հʣ 11

Slide 12

Slide 12 text

© DeNA Co., Ltd. ୯७ͳม׵Ͱ΋ಘΒΕΔޮՌ • ϝιουͷఆ͕͖ٛͬ͢Γ͢Δ • “public” / “void” ͕লུͰ͖Δ • 7จࣈ * 5ϝιου/೔ * 240೔ = ೥ؒͰ8,400จࣈઅ໿!! • ʮϝιουʹ੾Γग़͢΂͖ͩͱ໘౗ͩͳʯ
 ͱ͍͏ѱຐͷ੠ʹউͭ෢ثʹͳΔ
 12 Kotlin 11จࣈ Java 18จࣈ -7จࣈ

Slide 13

Slide 13 text

© DeNA Co., Ltd. ؆୯ʹऔΓೖΕΒΕΔ
 Kotlinػೳ͕͋Δͬͯຊ౰ʁ ʢ۩ମྫ1͚ͭͩ͝঺հʣ 13

Slide 14

Slide 14 text

© DeNA Co., Ltd. ؆୯ʹಋೖͰ͖ΔKotlinػೳ • anyϝιου • Ϧετ಺ʹ৚݅Λຬͨ͢ཁૉ͕͋Δ͔Λ൑ఆ • ࣮૷ͷҙਤ͕ඇৗʹ໌֬ʹͳΔ 14 any for in

Slide 15

Slide 15 text

© DeNA Co., Ltd. 15 ڧྗͳػೳ΋ͨ͘͞Μ͋Δ͚Ͳ ͪΓ΋ੵ΋Ε͹ࢁͱͳΔΑ͏ͳ ࡉ͔͍ޮՌ΋,PUMJOͷັྗ

Slide 16

Slide 16 text

16 © DeNA Co., Ltd. ·ͱΊ KotlinΛ
 ΋ͬͱ޷͖ʹͳΓ ίʔυΛ΋ͬͱ
 ͖Ε͍ʹ͠Α͏

Slide 17

Slide 17 text

© DeNA Co., Ltd. એ఻ ٕज़ॻయͰຊΛग़͠·͢ ɾ ೔ !஑ା ʮ+BWBUP,PUMJO
 ɹɹɹUP,PUMJO)BOECPPLʯ ɾࠓ೔ͷ֦େ൛ͷΑ͏ͳຊͰ͢ ɾ୯७ͳม׵ͰಘΒΕΔޮՌ΍
 ɹ؆୯ʹಋೖͰ͖Δػೳ΋
 ɹͨ͘͞Μ͝঺հ͍ͯ͠·͢ 17 ৄ͘͠͸ͪ͜Β↓ h5ps://techbookfest.org/event/tbf07/circle/5733885484728320