アニメリストのフェッチ方法 (#77)

[KOU050223]

GitHub issue #77: 初回のみフェッチするようにする
現在はアニメ一覧を取得しようとして10000件くらいのfirestoreの情報を毎回とってしまうのでDBにすごいダメージが出てしまう

Summary by CodeRabbit

• Refactor

  • Centralized anime list state into an application-wide provider, removing local view-model instantiation and simplifying lifecycle.
  • View now binds to the shared state and triggers a one-time fetch on first display to avoid redundant loads.

• New Features

  • Added a fetch-control flag and a public indicator to allow forced refreshes and to track whether an initial server fetch has occurred.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[coderabbitai]

📝 Walkthrough

Walkthrough

Promotes AnimeListViewModel to an application-wide ChangeNotifierProvider at app root; AnimeListPage now accesses the shared view model and triggers a one-time post-frame fetch (calling fetchFromServer(force:true) when needed). ViewModel adds _hasFetchedFromServer flag and a force parameter to fetchFromServer.

Changes

Cohort / File(s)	Summary
Provider setup & app root lib/app.dart	Wraps MaterialApp in MultiProvider, registering a global ChangeNotifierProvider<AnimeListViewModel>; adds imports for anime_list_view_model and provider.
Page-level access & fetch trigger lib/ui/animes/view/anime_list_page.dart	Removes local provider creation; uses Provider.of(context, listen: false) to obtain shared view model. Adds post-frame callback to call fetchFromServer(force: true) on first build when list is empty. Removes unused imports.
ViewModel API & fetch state lib/ui/animes/view_model/anime_list_view_model.dart	Adds private _hasFetchedFromServer and public bool get hasFetchedFromServer. Changes Future<void> fetchFromServer({bool force = false}) to skip when already fetched unless force is true; sets _hasFetchedFromServer = true on successful or fallback fetch paths.

Sequence Diagram

sequenceDiagram
    participant App as App
    participant Provider as MultiProvider
    participant Page as AnimeListPage
    participant VM as AnimeListViewModel
    participant Server as Server

    App->>Provider: Initialize MultiProvider with AnimeListViewModel
    Provider->>VM: Create shared instance (_hasFetchedFromServer = false)

    Page->>Provider: Provider.of(context, listen:false)
    Provider-->>Page: Shared ViewModel instance

    Page->>Page: Build -> detect empty list & not loading
    Page->>Page: Schedule post-frame callback
    Page->>VM: fetchFromServer(force: true)
    alt !_hasFetchedFromServer or force==true
        VM->>Server: Request anime data
        Server-->>VM: Return data / error
        VM->>VM: _hasFetchedFromServer = true
        VM-->>Page: notifyListeners (data available)
    else _hasFetchedFromServer == true and force==false
        VM-->>Page: Return early (skip fetch)
    end

    Page->>Page: Rebuild with updated state

Loading

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐇 A provider hopped into the app today,
Shared my list so all could play 🎬
Fetched once, or forced when called,
Carrots of state, never stalled 🥕
Hop happy, view synced all the way ✨

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description is incomplete compared to the template. It lacks sections for '変更内容' (detailed changes), テスト (test checklist), and other template sections, containing only a brief explanation of the issue.	Expand the description to follow the repository template structure: add '変更内容' section with specific changes, complete the '関連Issue' section, and fill in the テスト checklist with test verification status.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'アニメリストのフェッチ方法' accurately summarizes the main change of refactoring how anime list data is fetched to optimize Firestore queries, with issue reference #77.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

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[coderabbitai]

Actionable comments posted: 0

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

lib/ui/animes/view/anime_list_page.dart (1)

273-274: Fix syntax error causing pipeline failure.

The pipeline reports a Dart format parse error at lines 273-274. There appears to be an extra closing parenthesis. The Scaffold widget should close after the floatingActionButton parameter, but the current structure has unbalanced delimiters.

🐛 Proposed fix

             ),
           ),
-        ),
-      ),
+        )
     );
   }

Trace the widget tree: Scaffold opens at line 25 and takes body: and floatingActionButton:. After the FAB's Consumer closes at line 272, only one ); is needed to close the Scaffold and return statement.

🧹 Nitpick comments (1)

lib/ui/animes/view/anime_list_page.dart (1)

15-23: Consider using hasFetchedFromServer in the fetch condition.

The current condition !viewModel.isLoading && viewModel.animeList.isEmpty could trigger redundant addPostFrameCallback calls on rebuilds before data loads. While the ViewModel's _hasFetchedFromServer flag prevents actual Firestore reads, it would be cleaner to use this flag in the UI condition as well.

♻️ Proposed fix

     // 初回のみフェッチ
-    if (!viewModel.isLoading && viewModel.animeList.isEmpty) {
+    if (!viewModel.hasFetchedFromServer && !viewModel.isLoading) {
       WidgetsBinding.instance.addPostFrameCallback((_) {
         viewModel.fetchFromServer();
       });
     }

This directly leverages the caching flag and avoids repeated callback scheduling when the list happens to be empty for other reasons.

[coderabbitai]

Actionable comments posted: 1

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

lib/ui/animes/view/anime_list_page.dart (1)

230-274: Fix syntax error around floatingActionButton (CI parse failure).

There’s an extra closing parenthesis after the Consumer, which matches the formatter error (Line 273–274). Remove the stray ) so the Scaffold closes correctly.

🐛 Proposed fix

       floatingActionButton: Consumer<AnimeListViewModel>(
         builder: (context, viewModel, child) {
           ...
         },
       ),
-      ),
     );

🤖 Fix all issues with AI agents

In `@lib/ui/animes/view/anime_list_page.dart`:
- Around line 15-23: The initial fetch scheduling should be guarded by a new
hasFetchedFromServer flag on AnimeListViewModel so empty results or failures
don't cause repeated DB reads; modify the condition around
WidgetsBinding.instance.addPostFrameCallback to check
!viewModel.hasFetchedFromServer in addition to !viewModel.isLoading and
viewModel.animeList.isEmpty, and ensure fetchFromServer sets
hasFetchedFromServer = true (or set it immediately inside the post-frame
callback before/after calling fetchFromServer) so subsequent rebuilds won't
re-schedule the fetch; update AnimeListViewModel to expose and persist
hasFetchedFromServer accordingly.

[github-actions]

Visit the preview URL for this PR (updated for commit 53079d9):

https://animeishi-73560--pr164-vk-fe75-77-yddxa2nc.web.app

_{(expires Sun, 01 Feb 2026 19:22:25 GMT)}

_{🔥 via Firebase Hosting GitHub Action 🌎}

_{Sign: f1f494a67df8ccbb2232f73b6ccab4934a51e505}

[coderabbitai]

Actionable comments posted: 0

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

lib/ui/animes/view/anime_list_page.dart (1)

530-548: Using context after Navigator.pop() may cause a "deactivated widget" error.

After Navigator.of(context).pop() is called, the dialog's context is no longer mounted. Calling AnimeNotification.showSuccess/showError with this context will fail at runtime.

Capture the outer context or show the notification before popping, or use mounted check (though that requires a StatefulWidget).

Proposed fix: Show notification after returning from dialog

 confirmDismiss: (direction) async {
-  return await _showUnregisterDialog(
+  final result = await _showUnregisterDialog(
       context,
       viewModel,
       tid,
       anime['title'] ?? 'タイトル不明');
+  // Handle notification in the parent context after dialog closes
+  return result;
 },

Then move the notification logic to confirmDismiss or onDismissed callback where the parent context is still valid, or restructure _showUnregisterDialog to return a result and let the caller show the notification.

Alternatively, capture the ScaffoldMessenger before the async gap:

 onPressed: () async {
+  final messenger = ScaffoldMessenger.of(context);
+  final navigator = Navigator.of(context);
   try {
     viewModel.selectAnime(tid);
     await viewModel.deleteSelectedAnime();
-    Navigator.of(context).pop(true);
-    AnimeNotification.showSuccess(
-      context,
+    navigator.pop(true);
+    // Note: AnimeNotification needs refactoring to accept messenger
     ...