Paging Library は便利だぞ！

#hakata_apk で発表した際のスライドです．
# Android

Transcript

1. Paging Library͸ศརͩͧʂ # # #
2. ࣗݾ঺հ ▪ ;ͳͪʢHana Kondoʣ ▪ ٱཹถߴઐ ੍ޚ৘ใ޻ֶՊ 4೥ʢΪϦΪϦ18ࡀʣ ▪ AndroidΛ৮ΓॳΊͯ໿1.5೥͘Β͍ʁͷ·ͩ·ͩະख़ऀɽ ▪ Kotlin͕޷͖ɽ ▪ ॳΊͯͷ෦֎LTͰ͢ɽ ▪ ·͔͞Γ଴ͬͯ·͢ʂ @Hunachi @_hunachi
3. Paging Library ͱ͸? ▪ RecyclerView
   ඞཁͳ෼͚ͩঃʑʹऔಘͯ͘͠ΕΔɽ Ø εΫϩʔϧ͍ͯͬͯ͠ऴ୺ʹۙͣ͘ͱଓ͖ͷItemΛऔಘͯ͘͠ΕΔɽ ▪ ॳΊͯදʹݱΕͨͷ͸ڈ೥ͷ9݄ɽ ▪ Android JetPackͷҰһʂ ▪ ࠓ೥ͷ Google I/O Ͱ҆ఆ൛͕ϦϦʔε͞Εͨʂʢ͔ͩΒnew!ʣ
5. ▪ ແݶʹ௕͍ListΛऔಘ͍ͨ࣌͠΋ɼද͍ࣔͤͨ͞෼͚ͩ৘ใΛऔಘɽ Ø ແବͳ௨৴΍ϝϞϦΛ࢖Θͳ͍ɽ Ø εϜʔζʹߋ৽͞ΕΔͷͰɼUX͕޲্ɽ ▪ PagingΛࣗ෼Ͱ࣮૷͠ͳ͍͍͔ͯ͘Βָʂ ▪ Roomͱͷ૬ੑൈ܈ʂҰॹʹ࢖͏ͱΊͬͪΌָͰ͖Δʂ ▪  Data   OK Ø NetɼDataBaseɼFileɽɽɽ ࢖͏ར఺
6. ࢖͍ํ ᶃ ListAdapter Λ࢖ͬͨ RecyclerView Λ࡞Δɽ ᶄ ListAdapter -> PagedListAdapterʹ͢Δɽ ᶅ DataSource ͱ DataSource.Factory Λ࡞Δɽ ᶆ BuilderΛ࡞Δɽ ᶇ ViewModelʹLiveData<PagedList>Λ࡞Δɽ ᶈ submitListΛͯ͠׬੒ʂ Ͳ͏͍͏αΠΫϧͰಈ͔͘͸ɼCodelabͷWrap upʹॻ͍ͯ͋Δ ͷͰࠓճ͸࣮૷ํ๏ͷΈ঺հ͠·͢ɽ
7. https://www.youtube.com/watch?v=QVMqCRs0BNA
   
8. ListAdapter -> PagedListAdapterʹ͢Δɽ
9. DataSourceͱDataSource.FactoryΛ࡞Δɽ σʔλݩ͕େ͖͘෼͚Δͱɼ3έʔε͋Δɽ 1. DataBaseʢRoomͱซ༻ʣ 2. DataBase + OtherSourceʢ ྫ: NetWork ʣ 3. OtherSourceʢྫ: NetWork ʣ
10. DataBase
    Room ▪ List<Memo> -> DataSource.Factory<Int, Memo> ʹ͢Δ͚ͩɽ
11. DataBase + OtherSourceʢྫ: NetWork ʣ ▪ DB͔ΒσʔλΛऔಘ͠ɼσʔλ͕଍Γͳ͘ͳͬͨΒBoundaryCallbackʹ௨஌ɽ ▪ σʔλΛAPI౳͔Βऔ͖ͬͯͯɼDBΛߋ৽͢Δɽ ▪ PagingͷCodeLab͕͜ͷܗɽ https://codelabs.developers.google.com/codelabs/android-paging/
    .
12. ଓ͖ ▪ BoundaryCallback͸͜Μͳײ͡ɽ
13. OtherSourceʢྫ: NetWork ʣ ▪ DataSourceΛ͜Μͳײ͡Ͱ࡞Δɽʢ
    σʔλݩ͕ϖʔδϯάʹରԠ͍ͯ͠Δʣ
14. ଓ͖ ▪ DataͷऴΘΓ͸nullͰڭ͑ͯ͋͛Δɽ ▪ ΤϥʔϋϯυϦϯάɼϦτϥΠॲཧ౳͸ɼ Executorͱ͔LiveDataΛ࢖ͬͯؤு ΔʂʢެࣜͷαϯϓϧΛΈΔͱ͍͍ͱࢥ͍·͢ʂʣ ▪ σʔλݩ͕ϖʔδϯάʹରԠ͍ͯ͠Δ৔߹ Ø PageKeyedDataSource Λ࢖͏ɽ Ø callbackͷҾ਺͕ ListͱݱࡏͷPageɽ ▪ σʔλݩ͕ϖʔδϯάʹରԠ͍ͯ͠ͳ͍৔߹ Ø ItemKeyedDataSource Λ࢖͏ɽ Ø callbackͷҾ਺͕ Item ͷΈɽ
15. BuilderΛ࡞Δɽ
16. ࠷ޙʹsubmitList͢Δɽ 
17. ▪ )* Demo,/0 ▪ 5 1   #&-4  6 ! ▪ "$ ▪ https://github.com/Hunachi/wantedly-coding-challenge-publicNetWork ▪ https://github.com/Hunachi/HunaSchedule2 DataBase!%'(+2 3-.
18. ͝੩ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠ɽ