TCA v0.19.0からのSwitchStore/CaseLetが良い

Transcript

1. TCA v0.19.0͔Βͷ SwitchStore/CaseLet͕ྑ͍ QPUBUPUJQT
   
    @yimajo ͞Β͹͢΂ͯͷ
   *G-FU4UPSF
   ʹΑΔը໘දࣔ੾Γସ͑

2. ࣗݾ঺հ

3. w ిࢠॻ੶
   $PNCJOF
   ΨΠυϒοΫΛ ॻ͖·ͨ͠ͷͰങ͍ͬͯͩ͘͞
   w IUUQTTXJGUCPPUIQN
   w 5$"Λ࢓ࣄͰ΍ͬͯͯɺ΋ͬͱ஌ Γ͍ͨͱ͔ɺ৽͘͠΍͖͍ͬͯͨͱ ͍͏૊৫ͷਓ͸
   !ZJNBKP
   ·Ͱ%. ͔ϝʔϧΛ͍ͯͩ͘͠͞

4. ຊ୊

5. Effect View Store DI Environment TCA ( The Composable Architecture

   )ͱ͸ w J04ΞϓϦ։ൃͷͨΊͷ3FEVY෩ ຯͳ044
   w "QQMFͷެࣜϦΞΫςΟϒϓϩά ϥϛϯάϑϨʔϜϫʔΫͰ͋Δ $PNCJOFΛར༻͍ͯ͠Δ Reducerʢؔ਺ʣ State Action Combine @Published Combine Publisher

6. v0.19.0 w FOVNͳ4UBUFʹରԠ͢ΔDBTF
   QBUIͷ 3FEVDFSQVMMCBDL͕௥Ճ
   w FOVNͳ4UBUFΛݸʑͷ4UBUFʹม׵͢Δ 4XJUDI4UPSFͷ௥Ճ
   w & ff

   FDUUJNFS͕DBODFM*O'MJHIU
   USVFΛݺͼग़ͤΔΑ ͏ʹͳΓɺࣗಈతʹDBODFMMBCMF
   JE͕ಉ͡ͳΒ DBODFMͰ͖Δɻ
   w 'PS&BDI4UPSF͕վྑ

7. v0.19.0ͷ SwichStoreͱCaseLetʹ͍ͭͯ ExampleͷTicTacToeͰઆ໌

8. -PHJO
   7JFX /FX
   (BNF
   7JFX ىಈ ϩάΠϯ׬ྃ TicTacToeʢ3໨ฒ΂ʣήʔϜ

9. public enum AppState: Equatable { case login(LoginState) case newGame(NewGameState) public

   init() { self = .login(.init()) } } public struct AppState: Equatable { public var login: LoginState? = LoginState() public var newGame: NewGameState? public init() {} } public var body: some View { SwitchStore(self.store) { CaseLet( state: /AppState.login, action: AppAction.login ) { store in NavigationView { LoginView(store: store) } .navigationViewStyle(StackNavigationViewStyle()) } CaseLet( state: /AppState.newGame, action: AppAction.newGame ) { store in NavigationView { NewGameView(store: store) } .navigationViewStyle(StackNavigationViewStyle()) } } @ViewBuilder public var body: some View { IfLetStore( self.store.scope(state: \.login, action: AppAction.login) ) { store in NavigationView { LoginView(store: store) } .navigationViewStyle(StackNavigationViewStyle()) } IfLetStore( self.store.scope(state: \.newGame, action: AppAction.newGame) ) { store in NavigationView { NewGameView(store: store) } .navigationViewStyle(StackNavigationViewStyle()) } } Ҏલͷ΍Γํ 4XJUDI4UPSF$BTF-FU
   Ͱͷ΍Γํ 4XJGU6*7JFX 4XJGU6*7JFX 4UBUF 4UBUF

10. SwitchStore/CaseLet ͸ case͕໢ཏ͞Εͯͳ͚Ε͹ Τϥʔը໘Λදࣔͯ͘͠ΕΔ

11. SwitUI.View্Ͱ CaseLetͰ໢ཏͰ͖͍ͯ ͳ͍caseʹͳͬͨͱ͖ ਅͬ੺ͳը໘Ͱ
    $BTF-FUهࡌ͢Δ͔%FGBVMUΛ࢖͑
    ͱܯࠂ͞ΕΔ

12. public var body: some View { SwitchStore(self.store) { CaseLet( state:

    /AppState.login, action: AppAction.login ) { store in NavigationView { LoginView(store: store) } .navigationViewStyle(StackNavigationViewStyle()) } CaseLet( state: /AppState.newGame, action: AppAction.newGame ) { store in NavigationView { NewGameView(store: store) } .navigationViewStyle(StackNavigationViewStyle()) } Default { Text(“ະ࣮૷: ͋ͱͰ͍͍ײ͡ʹCaseLetॻ͘”) } } 4XJGU6*7JFX DefaultΛ࢖ͬͯΈΔྫ %FGBVMU͸։ൃ࣌͘Β͍ʹ࢖ͬͯجຊతʹ͸$BTF-FUͰ໢ཏ͠Α͏ public enum AppState: Equatable { case login(LoginState) case newGame(NewGameState) case foo(FooState) public init() { self = .login(.init()) } } 4UBUF

13. SwitchStore/CaseLetͷ Ԡ༻Λߟ͑ͯΈΔ

14. લఏ
    ϩάΠϯը໘͸
    ϩάΠϯࡁΈͳΒ
    දࣔ͠ͳ͍ -PHJO
    7JFX /FX
    (BNF
    7JFX ϩάΠϯ൑ఆ

    ͯ͠ ϩάΠϯͯͨ͠Β NewGameView ىಈ

15. -PHJO
    7JFX /FX
    (BNF
    7JFX ىಈ public enum AppState: Equatable

    { case launch(LaunchState) case login(LoginState) case newGame(NewGameState) public init() { self = .launch(.init()) } } -BVODI
    7JFX ϩάΠϯ ͯ͠ͳ͚Ε͹ LoginView ϩάΠϯͯ͠Ε͹ NewGameView Ԡ༻ྫ1 LaunchViewͰΞχϝʔγϣϯͱ͔Ͱ͖Δ

16. ىಈ public struct AppState: Equatable { enum Scene: Equatable {

    case login(LoginState) case newGame(NewGameState) } var scene: Scene var flag: Bool // ڞ௨ͳԿ͔ public init( scene: Scene = .loginCore(.init()) flag: Bool = false ) { self.scene = scene self.flag = flag } } 4UBUF -PHJO
    7JFX /FX
    (BNF
    7JFX ϩάΠϯ൑ఆ ͯ͠ NewGameView Ԡ༻ྫ2 ୹ॴ: CathPathͷ࢓༷Λཧղ͠ͳ͍ͱೲಘͰ͖ͳ͍΍ΓํʹͳΔ

17. ىಈ public struct RootState: Equatable { var appCore: AppCoreState var

    flag: Bool // ڞ௨ͳԿ͔ public init( appCore: AppCoreState = .loginState(.init()) flag: Bool = false ) { self.appCore = appCore self.flag = flag } } let reducer = Reducer.combine( appCoreReducer( // … ), Reducer { // … } ) 4UBUF -PHJO
    7JFX /FX
    (BNF
    7JFX ϩάΠϯ൑ఆ ͯ͠ NewGameView Ԡ༻ྫ2.1 public enum AppCoreState: Equatable { case login(LoginState) case newGame(NewGameState) } public enum AppCoreAction: Equatable { case login(LoginAction) case newGame(NewGameAction) } $PSFͱͯ͠FOVN
    4UBUFʹ͢Δ͕3PPU͸TUSVDU

18. ൃද͸Ҏ্Ͱ͢🙇 ʮ͞Β͹͢΂ͯͷ*G-FU4UPSFʹΑΔը໘දࣔ੾Γସ͑ʯ
    ͱ͍͏αϒλΠτϧͰ͕ͨ͠ɺ
    $BTF-FUͷͳ͔Ͱ͸*G-FU4UPSF͕࢖ΘΕ͍ͯ·͢ɻ