[#439] MainView의 destination ViewModel 생성 및 생명주기를 개선한다

.github/pull_request_template.md

@@ -3,10 +3,12 @@
 <!-- 이슈가 완전히 해결되었다면 아래에 예약어를 남겨주세요. -->
 - closed #이슈번호
 
+## 🎯 의도
+
 ## 📝 작업 내용
 
 ### 📌 요약
 
 ### 🔍 상세
 
-## 📸 영상 / 이미지 (Optional)
+## 📸 영상 / 이미지 (Optional)

DevLog/Presentation/ViewModel/TodoDetailViewModel.swift

@@ -40,11 +40,11 @@ final class TodoDetailViewModel: Store {
     }
 
     private(set) var state: State = .init()
+    let todoId: String
     let showEditButton: Bool
     private let fetchTodoUseCase: FetchTodoByIdUseCase
     private let fetchReferenceItemsUseCase: FetchReferenceItemsUseCase
     private let upsertUseCase: UpsertTodoUseCase
-    private let todoId: String
     private let loadingState = LoadingState()
 
     init(

DevLog/Presentation/ViewModel/TodoListViewModel.swift

@@ -13,7 +13,6 @@ final class TodoListViewModel: Store {
         var todos: [TodoListItem] = []
         var searchText: String = ""
         var searchResults: [TodoListItem] = []
-        let category: TodoCategory
         var showEditor: Bool = false
         var showAlert: Bool = false
         var alertTitle: String = ""
@@ -81,6 +80,7 @@ final class TodoListViewModel: Store {
         case request
     }
 
+    let category: TodoCategory
     private(set) var state: State
     private let fetchTodosUseCase: FetchTodosUseCase
     private let fetchTodoByIdUseCase: FetchTodoByIdUseCase
@@ -106,8 +106,8 @@ final class TodoListViewModel: Store {
         self.upsertTodoUseCase = upsertTodoUseCase
         self.deleteTodoUseCase = deleteTodoUseCase
         self.undoDeleteTodoUseCase = undoDeleteTodoUseCase
+        self.category = category
         self.state = State(
-            category: category,
             query: TodoQuery(category: category)
         )
     }
@@ -191,7 +191,7 @@ final class TodoListViewModel: Store {
                             self.endLoading(.immediate)
                         }
                     }
-                    let query = TodoQuery(category: state.category, keyword: keyword)
+                    let query = TodoQuery(category: category, keyword: keyword)
                     let page = try await fetchTodosUseCase.execute(query, cursor: nil)
                     if Task.isCancelled { return }
                     send(.fetchSearchResults(page.items.compactMap { TodoListItem(from: $0) }))
@@ -307,7 +307,7 @@ private extension TodoListViewModel {
             self.nextCursor = nil
             return [.fetch]
         case .resetFilters:
-            state.query = TodoQuery(category: state.category)
+            state.query = TodoQuery(category: category)
             self.nextCursor = nil
             return [.fetch]
         case .setIsSearching(let value):

DevLog/UI/Home/TodoListView.swift

@@ -45,7 +45,7 @@ struct TodoListView: View {
                     prompt: Text(
                         String.localizedStringWithFormat(
                             String(localized: "todo_list_search_prompt_format"),
-                            TodoCategoryItem(from: viewModel.state.category).localizedName
+                            TodoCategoryItem(from: viewModel.category).localizedName
                         )
                     )
                 )
@@ -71,14 +71,14 @@ struct TodoListView: View {
         ) {
             Label(viewModel.state.toastMessage, systemImage: "arrow.uturn.left")
         }
-        .navigationTitle(TodoCategoryItem(from: viewModel.state.category).localizedName)
+        .navigationTitle(TodoCategoryItem(from: viewModel.category).localizedName)
         .fullScreenCover(isPresented: Binding(
             get: { viewModel.state.showEditor },
             set: { viewModel.send(.setShowEditor($0)) }
         )) {
             TodoEditorView(
                 viewModel: TodoEditorViewModel(
-                    category: viewModel.state.category,
+                    category: viewModel.category,
                     fetchPreferencesUseCase: container.resolve(FetchTodoCategoryPreferencesUseCase.self),
                     fetchReferenceItemsUseCase: container.resolve(FetchReferenceItemsUseCase.self)
                 ),
@@ -222,7 +222,7 @@ struct TodoListView: View {
                 prompt: Text(
                     String.localizedStringWithFormat(
                         String(localized: "todo_list_search_prompt_format"),
-                        TodoCategoryItem(from: viewModel.state.category).localizedName
+                        TodoCategoryItem(from: viewModel.category).localizedName
                     )
                 )
             )
@@ -240,7 +240,7 @@ struct TodoListView: View {
             Text(
                 String.localizedStringWithFormat(
                     String(localized: "todo_list_search_instruction_format"),
-                    TodoCategoryItem(from: viewModel.state.category).localizedName
+                    TodoCategoryItem(from: viewModel.category).localizedName
                 )
             )
                 .foregroundStyle(Color.gray)

DevLog/UI/Main/MainView.swift

@@ -13,13 +13,11 @@ struct MainView: View {
     @State private var homeViewCoordinator: HomeViewCoordinator
     @State private var todayViewCoordinator: TodayViewCoordinator
     @Binding var selectedTab: MainTab
-    private let container: DIContainer
 
     init(
         container: DIContainer,
         selectedTab: Binding<MainTab>
     ) {
-        self.container = container
         self._coordinator = State(initialValue: MainViewCoordinator(container: container))
         self._homeViewCoordinator = State(initialValue: HomeViewCoordinator(container: container))
         self._todayViewCoordinator = State(initialValue: TodayViewCoordinator(container: container))
@@ -117,7 +115,7 @@ struct MainView: View {
                     Group {
                         if let todoId = coordinator.todoIdToPresent?.id {
                             TodoDetailView(
-                                viewModel: makeTodoDetailViewModel(
+                                viewModel: coordinator.todoDetailViewModel(
                                     todoId: todoId,
                                     showEditButton: false
                                 )
@@ -235,11 +233,11 @@ struct MainView: View {
         switch homeRoute {
         case .category(let item):
             TodoListView(
-                viewModel: makeTodoListViewModel(category: item.todoCategory)
+                viewModel: coordinator.todoListViewModel(category: item.todoCategory)
             )
             .id(item.id)
         case .todo(let item):
-            TodoDetailView(viewModel: makeTodoDetailViewModel(todoId: item.id))
+            TodoDetailView(viewModel: coordinator.todoDetailViewModel(todoId: item.id))
             .id(item.id)
         case .webPage(let item):
             WebView(url: item.url)
@@ -302,7 +300,7 @@ struct MainView: View {
     private func todayDestinationView(_ todayRoute: TodayRoute) -> some View {
         switch todayRoute {
         case .todo(let item):
-            TodoDetailView(viewModel: makeTodoDetailViewModel(todoId: item.id))
+            TodoDetailView(viewModel: coordinator.todoDetailViewModel(todoId: item.id))
                 .id(item.id)
         }
     }
@@ -378,29 +376,6 @@ private extension MainView {
         )
     }
 
-    func makeTodoListViewModel(category: TodoCategory) -> TodoListViewModel {
-        TodoListViewModel(
-            fetchTodosUseCase: container.resolve(FetchTodosUseCase.self),
-            fetchTodoByIdUseCase: container.resolve(FetchTodoByIdUseCase.self),
-            upsertTodoUseCase: container.resolve(UpsertTodoUseCase.self),
-            deleteTodoUseCase: container.resolve(DeleteTodoUseCase.self),
-            undoDeleteTodoUseCase: container.resolve(UndoDeleteTodoUseCase.self),
-            category: category
-        )
-    }
-
-    func makeTodoDetailViewModel(
-        todoId: String,
-        showEditButton: Bool = true
-    ) -> TodoDetailViewModel {
-        TodoDetailViewModel(
-            fetchTodoUseCase: container.resolve(FetchTodoByIdUseCase.self),
-            fetchReferenceItemsUseCase: container.resolve(FetchReferenceItemsUseCase.self),
-            upsertUseCase: container.resolve(UpsertTodoUseCase.self),
-            todoId: todoId,
-            showEditButton: showEditButton
-        )
-    }
 }
 
 private enum MainTabSplitStyle {

DevLog/UI/Main/MainViewCoordinator.swift

@@ -14,8 +14,14 @@ final class MainViewCoordinator {
     let pushNotificationListViewModel: PushNotificationListViewModel
     let profileViewModel: ProfileViewModel
     var todoIdToPresent: TodoIdItem?
+    private let diContainer: DIContainer
+    @ObservationIgnored
+    private var todoListViewModel: TodoListViewModel?
+    @ObservationIgnored
+    private var todoDetailViewModel: TodoDetailViewModel?
 
     init(container: DIContainer) {
+        self.diContainer = container
         self.mainViewModel = MainViewModel(
             unreadPushCountUseCase: container.resolve(ObserveUnreadPushCountUseCase.self)
         )
@@ -36,4 +42,43 @@ final class MainViewCoordinator {
             updateHeatmapActivityTypesUseCase: container.resolve(UpdateHeatmapActivityTypesUseCase.self)
         )
     }
+
+    func todoListViewModel(category: TodoCategory) -> TodoListViewModel {
+        if let todoListViewModel,
+           todoListViewModel.category == category {
+            return todoListViewModel
+        }
+
+        let todoListViewModel = TodoListViewModel(
+            fetchTodosUseCase: diContainer.resolve(FetchTodosUseCase.self),
+            fetchTodoByIdUseCase: diContainer.resolve(FetchTodoByIdUseCase.self),
+            upsertTodoUseCase: diContainer.resolve(UpsertTodoUseCase.self),
+            deleteTodoUseCase: diContainer.resolve(DeleteTodoUseCase.self),
+            undoDeleteTodoUseCase: diContainer.resolve(UndoDeleteTodoUseCase.self),
+            category: category
+        )
+        self.todoListViewModel = todoListViewModel
+        return todoListViewModel
+    }
+
+    func todoDetailViewModel(
+        todoId: String,
+        showEditButton: Bool = true
+    ) -> TodoDetailViewModel {
+        if let todoDetailViewModel,
+           todoDetailViewModel.todoId == todoId,
+           todoDetailViewModel.showEditButton == showEditButton {
+            return todoDetailViewModel
+        }
+
+        let todoDetailViewModel = TodoDetailViewModel(
+            fetchTodoUseCase: diContainer.resolve(FetchTodoByIdUseCase.self),
+            fetchReferenceItemsUseCase: diContainer.resolve(FetchReferenceItemsUseCase.self),
+            upsertUseCase: diContainer.resolve(UpsertTodoUseCase.self),
+            todoId: todoId,
+            showEditButton: showEditButton
+        )
+        self.todoDetailViewModel = todoDetailViewModel
+        return todoDetailViewModel
+    }
 }