Xcode Previewを気軽に利用するためのDI戦略

Xcode Previewでは静的なUIだけでなく、実際にUIを操作して簡単な動作確認ができます。

Xcode Previewを本格的に使うにはDependency Injection(DI)をする必要がありますが、SwiftUIのViewへのDIはアプリのトップレベルから依存をパスする、所謂バケツリレーが必要で、実装コストが大きくなってしまいます。
一方@Environment(Object)だとバケツリレーせずにDIできますが、コンパイラの力を借りることができず、Xcode Previewへのハードルが上がります。
そこでこのトークでは、Xcode Previewのことを最優先に考え、開発者が「いつでも」「気軽に」「安全に」Xcode Previewを利用できるDI戦略を紹介します。

このトークを通じて、みなさんがもっと気軽にXcode Previewを使い倒せることを目指します。

Transcript

1. View Slide

2. Xcode Preview
   1
   

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3. 1 Xcode PreviewͰͷDIઓུͱͦͷ՝୊
   2 ண؟఺ͱղܾํ๏
   

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4. 1 Xcode PreviewͰͷDIઓུͱͦͷ՝୊
   2 ண؟఺ͱղܾํ๏
   

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5. Qiita Viewer
   QiitaͷهࣄΛݕࡧͯ͠ɺ୺຤ʹอଘ͢ΔΞϓϦ
   https://github.com/mtj0928/QiitaViewer
   4
   

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6. View Slide

7. App
   อଘࡁΈهࣄͷҰཡ
   ΞΧ΢ϯτઃఆ
   هࣄͷݕࡧ
   هࣄͷৄࡉ
   6
   

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8. App
   อଘࡁΈهࣄͷҰཡ
   ΞΧ΢ϯτઃఆ
   هࣄͷݕࡧ
   هࣄͷৄࡉ
   6
   

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9. struct ItemListView: View {
   @StateObject let viewModel = ItemListViewModel()
   var body: some View {
   // viewModelͷitemsΛ࢖ͬͯϦετΛදࣔ͢Δ
   }
   }
   class ItemListViewModel: ObservableObject {
   @Published var items: [Item] = []
   func fetchItems() async throws {
   items = try await APIClient.share.getItems()
   }
   }
   7
   

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10. struct ItemListView: View {
    @StateObject let viewModel = ItemListViewModel()
    var body: some View {
    // viewModelͷitemsΛ࢖ͬͯϦετΛදࣔ͢Δ
    }
    }
    class ItemListViewModel: ObservableObject {
    @Published var items: [Item] = []
    func fetchItems() async throws {
    items = try await APIClient.share.getItems()
    }
    }
    ViewModelΛ
    StateObjectͰ؅ཧ
    7
    

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11. struct ItemListView: View {
    @StateObject let viewModel = ItemListViewModel()
    var body: some View {
    // viewModelͷitemsΛ࢖ͬͯϦετΛදࣔ͢Δ
    }
    }
    class ItemListViewModel: ObservableObject {
    @Published var items: [Item] = []
    func fetchItems() async throws {
    items = try await APIClient.share.getItems()
    }
    }
    ViewModelΛ
    StateObjectͰ؅ཧ
    APIܦ༝ͰitemsΛऔಘ
    7
    

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12. struct ItemListView_Previews: PreviewProvider {
    static var previews: some View {
    ItemListView()
    }
    }
    8
    

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13. Xcode PreviewΛ࢖͏্Ͱͷ໰୊఺
    // ViewModelͷதͷؔ਺
    func fetchItems() async throws {
    items = try await APIClient.share.getItems()
    }
    9
    

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14. Xcode PreviewΛ࢖͏্Ͱͷ໰୊఺
    // ViewModelͷதͷؔ਺
    func fetchItems() async throws {
    items = try await APIClient.share.getItems()
    }
    ຖճAPIͷݺͼग़͕͠૸ͬͯ͠·͏
    9
    

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15. Xcode PreviewΛ࢖͏্Ͱͷ໰୊఺
    // ViewModelͷதͷؔ਺
    func fetchItems() async throws {
    items = try await APIClient.share.getItems()
    }
    ຖճAPIͷݺͼग़͕͠૸ͬͯ͠·͏
    UIͷεςʔλεͷίϯτϩʔϧ͕Ͱ͖ͳ͍
    APIͷݺͼग़͠ʹ੒ޭͨ࣌͠ͷUI
    APIͷݺͼग़͠ʹࣦഊͨ࣌͠ͷUI
    APIΛݺͼग़͍ͯ͠ΔؒͷUI
    9
    

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16. Dependency Injection
    

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17. Initializer Injection
    

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18. protocol APIClientProtocol {
    func getItems() async throws -> [Item]
    }
    class ItemListViewModel: ObservableObject {
    @Published var items: [Item] = []
    let apiClient: APIClientProtocol
    init(apiClient: APIClientProtocol) {
    self.apiClient = apiClient
    }
    func fetchItems() async throws {
    items = try await apiClient.getItems()
    }
    }
    12
    

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19. protocol APIClientProtocol {
    func getItems() async throws -> [Item]
    }
    class ItemListViewModel: ObservableObject {
    @Published var items: [Item] = []
    let apiClient: APIClientProtocol
    init(apiClient: APIClientProtocol) {
    self.apiClient = apiClient
    }
    func fetchItems() async throws {
    items = try await apiClient.getItems()
    }
    }
    APIClient༻ʹprotocolΛఆٛ
    12
    

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20. protocol APIClientProtocol {
    func getItems() async throws -> [Item]
    }
    class ItemListViewModel: ObservableObject {
    @Published var items: [Item] = []
    let apiClient: APIClientProtocol
    init(apiClient: APIClientProtocol) {
    self.apiClient = apiClient
    }
    func fetchItems() async throws {
    items = try await apiClient.getItems()
    }
    }
    APIClient༻ʹprotocolΛఆٛ
    protocolΛinitͰࠩ͠ࠐΉ
    12
    

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21. protocol APIClientProtocol {
    func getItems() async throws -> [Item]
    }
    class ItemListViewModel: ObservableObject {
    @Published var items: [Item] = []
    let apiClient: APIClientProtocol
    init(apiClient: APIClientProtocol) {
    self.apiClient = apiClient
    }
    func fetchItems() async throws {
    items = try await apiClient.getItems()
    }
    }
    APIClient༻ʹprotocolΛఆٛ
    protocolΛinitͰࠩ͠ࠐΉ
    γϯάϧτϯͷ୅ΘΓʹ
    DI͞ΕͨAPIClinetΛ࢖͏
    12
    

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22. struct ItemListView: View {
    @StateObject let viewModel: ItemListViewModel
    var body: some View {
    // viewModelͷitemsΛ࢖ͬͯϦετΛදࣔ͢Δ
    }
    }
    13
    

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23. struct ItemListView: View {
    @StateObject let viewModel: ItemListViewModel
    var body: some View {
    // viewModelͷitemsΛ࢖ͬͯϦετΛදࣔ͢Δ
    }
    }
    ViewModelΛ֎͔Βࠩ͠ࠐΉ
    13
    

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24. private struct MockAPIClient: APIClientProtocol {
    func getItems() async throws -> [Item] {
    // ϞοΫ͍ͨ͠ॲཧΛ͜͜ʹೖΕΔ
    }
    }
    struct ItemListView_Previews: PreviewProvider {
    static var previews: some View {
    let apiClient = MockAPIClient()
    let viewModel = ItemListViewModel(apiClient: apiClient)
    ItemListView(viewModel: viewModel)
    }
    }
    14
    

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25. Initializer Injection
    Ұ൪҆શͳDIख๏
    ίϯύΠϧ࣌ʹDI͞Ε͍ͯΔ͜ͱΛอূͰ͖Δ
    ґଘͷόέπϦϨʔ͕ඞཁ
    15
    

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26. Initializer Injection
    Ұ൪҆શͳDIख๏
    ίϯύΠϧ࣌ʹDI͞Ε͍ͯΔ͜ͱΛอূͰ͖Δ
    ґଘͷόέπϦϨʔ͕ඞཁ
    15
    

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27. App
    อଘࡁΈهࣄͷҰཡ
    ΞΧ΢ϯτઃఆ
    هࣄͷݕࡧ
    هࣄͷৄࡉ
    16
    

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28. App
    อଘࡁΈهࣄͷҰཡ
    ΞΧ΢ϯτઃఆ
    هࣄͷݕࡧ
    هࣄͷৄࡉ
    APIClient͕ඞཁ
    16
    

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29. App
    อଘࡁΈهࣄͷҰཡ
    ΞΧ΢ϯτઃఆ
    هࣄͷݕࡧ
    هࣄͷৄࡉ
    APIClient͕ඞཁ
    DB͕ඞཁ
    16
    

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30. App
    อଘࡁΈهࣄͷҰཡ
    ΞΧ΢ϯτઃఆ
    هࣄͷݕࡧ
    هࣄͷৄࡉ
    APIClientͱDBΛ౉͢
    APIClient͕ඞཁ
    DB͕ඞཁ
    16
    

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31. όέπϦϨʔͷ՝୊
    ݕࡧը໘͸APIΛୟ͚ͩ͘ͳͷʹɺDBͷ৘ใ΋౉͢ඞཁ͕͋Δ
    ItemListView(
    viewModel: ItemListViewModel(apiClient: MockAPIClient()),
    db: MockDatabase()
    )
    17
    

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32. όέπϦϨʔͷ՝୊
    ݕࡧը໘͸APIΛୟ͚ͩ͘ͳͷʹɺDBͷ৘ใ΋౉͢ඞཁ͕͋Δ
    ItemListView(
    viewModel: ItemListViewModel(apiClient: MockAPIClient()),
    db: MockDatabase()
    )
    ͜Εඞཁ...ʁ
    17
    

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33. όέπϦϨʔͷ՝୊
    ݕࡧը໘͸APIΛୟ͚ͩ͘ͳͷʹɺDBͷ৘ใ΋౉͢ඞཁ͕͋Δ
    ItemListView(
    viewModel: ItemListViewModel(apiClient: MockAPIClient()),
    db: MockDatabase(),
    keychain: MockKeychain(),
    fileManager: MockFileManager(),
    userDefaults: MockUserDefaults(),
    authManager: MockAuthManager(),
    logger: MockLogger(),
    ...
    )
    17
    

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34. όέπϦϨʔͷ՝୊
    ݕࡧը໘͸APIΛୟ͚ͩ͘ͳͷʹɺDBͷ৘ใ΋౉͢ඞཁ͕͋Δ
    ItemListView(
    viewModel: ItemListViewModel(apiClient: MockAPIClient()),
    db: MockDatabase(),
    keychain: MockKeychain(),
    fileManager: MockFileManager(),
    userDefaults: MockUserDefaults(),
    authManager: MockAuthManager(),
    logger: MockLogger(),
    ...
    )
    ը໘਺͕૿͑Ε͹૿͑Δ΄ͲXcode Previewʹ౉͢ґଘ͕૿͑Δ
    17
    

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35. όέπϦϨʔͷ՝୊
    ը໘ͷ਺͕૿͑Δ΄Ͳඞཁͳґଘ͕૿͑ͯɺXcode PreviewΛ
    ؾܰʹࢼͤͳ͘ͳΔ
    18
    

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36. όέπϦϨʔͷ՝୊
    ը໘ͷ਺͕૿͑Δ΄Ͳඞཁͳґଘ͕૿͑ͯɺXcode PreviewΛ
    ؾܰʹࢼͤͳ͘ͳΔ
    ର৅ͷView͕ͲͷґଘΛ࣮ࡍʹૢ࡞͢Δͷ͔ݺͼग़͠ଆ͸Θ͔Βͳ͍
    DBΛ৮Δͷ͔ɺͦΕͱ΋APIΛୟ͘ͷ͔
    Xcode Preview࣌ʹԿΛϞοΫ͢ΔͱͲ͏൓ө͞ΕΔͷ͔ͷ೺Ѳ͕೉͘͠ͳΔ
    18
    

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37. @Environment
    @EnvironmentObject
    

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38. RootView()
    .environment(\.apiClient, APIClient())
    .environment(\.database, Database())
    struct ItemListView: View {
    @Environment(\.apiClient) var apiClient: APIClientProtocol
    }
    20
    

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39. @Environmentͷ՝୊
    1. ඞཁͳґଘ͕Θ͔Βͳ͍
    struct ItemListView_Previews: PreviewProvider {
    static var previews: some View {
    ItemListView()
    .environment(\.apiClient, MockAPIClient())
    }
    }
    21
    

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40. @Environmentͷ՝୊
    1. ඞཁͳґଘ͕Θ͔Βͳ͍
    struct ItemListView_Previews: PreviewProvider {
    static var previews: some View {
    ItemListView()
    .environment(\.apiClient, MockAPIClient())
    }
    }
    ͜ΕΛ๨Εͯ΋ίϯύΠϧΤϥʔʹͳΒͳ͍
    21
    

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41. @Environmentͷ՝୊
    2. initͰΞΫηε͕Ͱ͖ͳ͍
    struct ItemListView: View {
    @Environment(\.apiClient) var apiClient: APIClientProtocol?
    @StateObject var viewModel: ItemListViewModel
    init() {
    self.viewModel = ItemListViewModel(apiClient: apiClient)
    }
    var body: some View { ... }
    }
    22
    

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42. @Environmentͷ՝୊
    2. initͰΞΫηε͕Ͱ͖ͳ͍
    struct ItemListView: View {
    @Environment(\.apiClient) var apiClient: APIClientProtocol?
    @StateObject var viewModel: ItemListViewModel
    init() {
    self.viewModel = ItemListViewModel(apiClient: apiClient)
    }
    var body: some View { ... }
    }
    initͰEnvironmentͷ஋ʹΞΫηεͰ͖ͣ
    ViewModel͕࡞Εͳ͍
    22
    

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43. ՝୊ͷཁ໿
    Initializer Injection
    ը໘ͷ਺͕૿͑Δ΄Ͳ౉͢ґଘ͕૿͑ͯɺXcode PreviewΛࢼ͠ʹ͘͘ͳΔ
    Ͳͷґଘ͕Xcode Previewʹ࣮ࡍʹඞཁͳґଘ͔ᐆດʹͳΔ
    @Environment
    ԿΛDI͢Δ΂͖͔ɺίϯύΠϥ͸Θ͔Βͳ͍
    initͰ͸ΞΫηεͰ͖ͳ͍ͷͰɺObservableObjectΛ࡞Δʹ͸޻෉͕ඞཁ
    23
    

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44. 1 Xcode PreviewͰͷDIઓུͱͦͷ՝୊
    2 ண؟఺ͱղܾํ๏
    

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45. Xcode Previewͷؔ৺ൣғ
    Xcode Preview࣌ͷؔ৺͸ର৅ͷը໘͚ͩͰ͋Γɺଞͷը໘ʹؔ৺͸ͳ͍
    struct ItemListView: View { ... }
    struct ItemListView_Previews: PreviewProvider {
    static var previews: some View {
    ItemListView(viewModel: ...)
    }
    }
    25
    

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46. Xcode Previewͷؔ৺ൣғ
    Xcode Preview࣌ͷؔ৺͸ର৅ͷը໘͚ͩͰ͋Γɺଞͷը໘ʹؔ৺͸ͳ͍
    struct ItemListView: View { ... }
    struct ItemListView_Previews: PreviewProvider {
    static var previews: some View {
    ItemListView(viewModel: ...)
    }
    }
    ItemListViewʹ͚ͩڵຯ͕͋Γ
    ભҠઌͷը໘ʹڵຯ͸ͳ͍
    25
    

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47. App
    هࣄͷݕࡧ
    อଘࡁΈهࣄͷҰཡ
    ΞΧ΢ϯτઃఆ
    هࣄͷৄࡉ
    26
    

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48. App
    ؔ৺಺
    هࣄͷݕࡧ
    ؔ৺಺
    อଘࡁΈهࣄͷҰཡ
    ؔ৺಺
    ΞΧ΢ϯτઃఆ
    ؔ৺಺
    هࣄͷৄࡉ
    26
    

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49. App
    ؔ৺֎ ؔ৺಺
    هࣄͷݕࡧ
    ؔ৺಺
    อଘࡁΈهࣄͷҰཡ
    ؔ৺಺
    ΞΧ΢ϯτઃఆ
    ؔ৺಺
    هࣄͷৄࡉ
    ؔ৺֎
    26
    

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50. App
    ؔ৺֎ ؔ৺಺
    هࣄͷݕࡧ
    Initializer Injection
    ؔ৺಺
    อଘࡁΈهࣄͷҰཡ
    ؔ৺಺
    ΞΧ΢ϯτઃఆ
    ؔ৺಺
    هࣄͷৄࡉ
    ؔ৺֎
    26
    

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51. App
    ؔ৺֎ ؔ৺಺
    هࣄͷݕࡧ
    Initializer Injection
    ؔ৺಺
    อଘࡁΈهࣄͷҰཡ
    ؔ৺಺
    ΞΧ΢ϯτઃఆ
    ؔ৺಺
    هࣄͷৄࡉ
    ؔ৺֎
    @Environment
    26
    

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52. Dependency Provider
    27
    

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53. DependencyProvider
    1. DI͍ͨ͠ΦϒδΣΫτΛ·ͱΊͨstructΛ࡞Δ
    struct AppDependency {
    let apiClient: APIClientProtocol
    let database: DatabaseProtocol
    }
    28
    

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54. DependencyProvider
    2. AppDependencyΛEnvironmentʹ౉͢
    let dependency = AppDependency(
    apiClient: APIClient(),
    database: Database()
    )
    AppRootView()
    .environment(\.dependency, dependency)
    29
    

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55. DependencyProvider
    3. Environment͔ΒґଘΛऔΓग़͠ɺunwrap͢ΔViewΛ࡞Δ
    struct DependencyProvider: View {
    @Environment(\.dependency) var dependency: AppDependency?
    let childView: (AppDependency) -> ChildView
    var body: some View {
    if let dependency {
    childView(dependency)
    } else {
    #if DEBUG
    Text("Dependency is not set.")
    // ...
    .background(.red)
    #endif 30
    

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56. DependencyProvider
    3. Environment͔ΒґଘΛऔΓग़͠ɺunwrap͢ΔViewΛ࡞Δ
    struct DependencyProvider: View {
    @Environment(\.dependency) var dependency: AppDependency?
    let childView: (AppDependency) -> ChildView
    var body: some View {
    if let dependency {
    childView(dependency)
    } else {
    #if DEBUG
    Text("Dependency is not set.")
    // ...
    .background(.red)
    #endif
    Environment͔Β
    ґଘΛऔΓग़͢
    30
    

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57. DependencyProvider
    3. Environment͔ΒґଘΛऔΓग़͠ɺunwrap͢ΔViewΛ࡞Δ
    struct DependencyProvider: View {
    @Environment(\.dependency) var dependency: AppDependency?
    let childView: (AppDependency) -> ChildView
    var body: some View {
    if let dependency {
    childView(dependency)
    } else {
    #if DEBUG
    Text("Dependency is not set.")
    // ...
    .background(.red)
    #endif
    ChildViewΛ֎͔Βࠩ͠ࠐΉ
    30
    

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58. DependencyProvider
    3. Environment͔ΒґଘΛऔΓग़͠ɺunwrap͢ΔViewΛ࡞Δ
    struct DependencyProvider: View {
    @Environment(\.dependency) var dependency: AppDependency?
    let childView: (AppDependency) -> ChildView
    var body: some View {
    if let dependency {
    childView(dependency)
    } else {
    #if DEBUG
    Text("Dependency is not set.")
    // ...
    .background(.red)
    #endif
    ґଘ͕஫ೖ͞Ε͍ͯΕ͹
    ґଘͱڞʹChildViewΛग़͢
    30
    

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59. DependencyProvider
    3. Environment͔ΒґଘΛऔΓग़͠ɺunwrap͢ΔViewΛ࡞Δ
    struct DependencyProvider: View {
    @Environment(\.dependency) var dependency: AppDependency?
    let childView: (AppDependency) -> ChildView
    var body: some View {
    if let dependency {
    childView(dependency)
    } else {
    #if DEBUG
    Text("Dependency is not set.")
    // ...
    .background(.red)
    #endif
    }
    ґଘ͕஫ೖ͞Ε͍ͯͳ͔ͬͨΒ
    ͦͷ͜ͱΛදࣔ͢Δ
    30
    

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60. DependencyProviderͷ࢖͍ํ
    1. ֤ViewͷinitͰ͸ͦͷView͕ඞཁͳґଘ͚ͩΛએݴ͢Δ
    struct ItemListView: View {
    init(viewModel: ItemListViewModel) {
    ...
    }
    }
    31
    

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61. DependencyProviderͷ࢖͍ํ
    1. ֤ViewͷinitͰ͸ͦͷView͕ඞཁͳґଘ͚ͩΛએݴ͢Δ
    struct ItemListView: View {
    init(viewModel: ItemListViewModel) {
    ...
    }
    }
    struct ItemListView_Previews: PreviewProvider {
    static var previews: some View {
    let viewModel = ItemListViewModel(apiClient: MockAPIClient())
    ItemListView(viewModel: viewModel)
    }
    }
    31
    

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62. DependencyProviderͷ࢖͍ํ
    2. ଞͷViewΛදࣔ͢Δ࣌ɺDependency ProviderΛڬΜͰґଘΛղܾ͢Δ
    var body: some View {
    ...
    .navigationDestination(for: Item.self) { item in
    }
    }
    32
    

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63. DependencyProviderͷ࢖͍ํ
    2. ଞͷViewΛදࣔ͢Δ࣌ɺDependency ProviderΛڬΜͰґଘΛղܾ͢Δ
    var body: some View {
    ...
    .navigationDestination(for: Item.self) { item in
    DependencyProvider {
    }
    }
    }
    ·ͣDependencyProviderΛݺͿ
    32
    

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64. DependencyProviderͷ࢖͍ํ
    2. ଞͷViewΛදࣔ͢Δ࣌ɺDependency ProviderΛڬΜͰґଘΛղܾ͢Δ
    var body: some View {
    ...
    .navigationDestination(for: Item.self) { item in
    DependencyProvider { dependency in
    }
    }
    }
    ґଘ͕౉͞ΕΔ
    32
    

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65. DependencyProviderͷ࢖͍ํ
    2. ଞͷViewΛදࣔ͢Δ࣌ɺDependency ProviderΛڬΜͰґଘΛղܾ͢Δ
    var body: some View {
    ...
    .navigationDestination(for: Item.self) { item in
    DependencyProvider { dependency in
    ItemDetailView(
    item,
    database: dependency.database
    )
    }
    }
    }
    ౉͞ΕͨґଘΛ࢖ͬͯ
    Child ViewΛ࡞Δ
    32
    

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66. View Slide

67. DependencyProviderͷԿ͕خ͍͔͠
    1. ͲͷView͔ΒͰ΋ґଘ͕औΓग़ͤΔ
    non-optionalͳ஋ͱͯ͠औΓग़ͤΔ
    struct FooView: View {
    var body: some View {
    NavigationLink("࣍ͷը໘΁") {
    DependencyProvider { dependency in
    NextView(database: dependency.database)
    }
    }
    }
    }
    34
    

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68. DependencyProviderͷԿ͕خ͍͔͠
    2. ֤View͸ඞཁͳґଘ͚ͩΛinitͰએݴͰ͖Δ
    ભҠઌͷը໘ͷͨΊͷґଘ͸ඞཁͳ͍
    Xcode PreviewΛར༻͢ΔͨΊͷඞཁे෼ͳґଘΛίϯύΠϥ͕஌ΕΔ
    ݺͼग़͠ଆ͕ͲͷΑ͏ʹґଘղܾΛ͍ͯ͠Δͷ͔஌Δඞཁ͸ͳ͍
    35
    

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69. DependencyProviderͷԿ͕خ͍͔͠
    3. EnvironmentͷઃఆΛ๨ΕΔ͜ͱ͕ͳ͍
    AppDependencyͷઃఆ͸1ճͰྑ͍
    Ծʹઃఆ͠๨Ε͍ͯͨΒࢸΔͱ͜ΖͰը໘͕ਅͬ੺ʹͳΔͷͰɺ͙͢ʹؾ෇͚Δ
    ґଘΛ௥Ճ͢Δ࣌͸ɺAppDependencyʹϓϩύςΟΛ௥Ճ͢Δ
    AppDependencyΛ࡞͍ͬͯΔՕॴͰઃఆ࿙Ε͕͋ͬͨΒίϯύΠϧΤϥʔʹͳΔ
    36
    

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70. DependencyProviderͷԿ͕خ͍͔͠
    4. DIͷํ๏͕View૚Ͱด͍ͯ͡Δ
    ϓϨθϯςʔγϣϯ૚΍ϏδωεϩδοΫ૚Ͱ͸γϯϓϧͳ
    Initializer InjectionΛҡ࣋Ͱ͖Δ
    ୯ମςετͰ͸DependencyProviderʹґଘ͢Δඞཁ͕ͳ͍
    37
    

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71. Ͱ΋͜ͷํ๏ͬͯSwiftUI͚ͩͰ͢ΑͶʁ
    

    View Slide

72. iOS17͔Β͸UIKitͰ΋Ͱ͖·͢
    UITraitCollectionͰSwiftUIͷEnvironmentͱಉ༷ͷ͜ͱ͕Մೳʹʂ
    ৄ͘͠͸WWDCͷηογϣϯಈըΛࢀর͍ͯͩ͘͠͞
    https://developer.apple.com/videos/play/wwdc2023/10057/
    39
    

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73. ·ͱΊ
    Xcode PreviewΛຊ֨తʹ࢖͏ʹ͸DI͸ॏཁͳςʔϚ
    Initializer Injection΍Environment͸ͦΕͧΕ՝୊͕ଘࡏ
    ͦΕͧΕͷྑ͍ͱ͜ͲΓͳDependencyProviderΛఏҊ
    iOS17͔Β͸UIKitͰಉ༷ͷ͜ͱ͕Ͱ͖Δ͔΋...ʁ
    40
    

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74. ·ͱΊ
    Xcode PreviewΛຊ֨తʹ࢖͏ʹ͸DI͸ॏཁͳςʔϚ
    Initializer Injection΍Environment͸ͦΕͧΕ՝୊͕ଘࡏ
    ͦΕͧΕͷྑ͍ͱ͜ͲΓͳDependencyProviderΛఏҊ
    iOS17͔Β͸UIKitͰಉ༷ͷ͜ͱ͕Ͱ͖Δ͔΋...ʁ
    Ξϯέʔτ/ϑΟʔυόοΫ଴͍ͬͯ·͢ʂ
    40
    

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