♻️ Post list controller layer

lib/controllers/post_list_controller.dart

@@ -0,0 +1,109 @@
+import 'package:get/get.dart';
+import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
+import 'package:solian/models/pagination.dart';
+import 'package:solian/models/post.dart';
+
+import '../providers/content/posts.dart';
+
+class PostListController {
+  /// The polling source modifier.
+  /// - `0`: default recommendations
+  /// - `1`: shuffle mode
+  RxInt mode = 0.obs;
+
+  /// The paging controller for infinite loading.
+  /// Only available when mode is `0`.
+  PagingController<int, Post> pagingController =
+  PagingController(firstPageKey: 0);
+
+  PostListController() {
+    _initPagingController();
+  }
+
+  /// Initialize a compatibility layer to paging controller
+  void _initPagingController() {
+    pagingController.addPageRequestListener(_onPagingControllerRequest);
+  }
+
+  Future<void> _onPagingControllerRequest(int pageKey) async {
+    try {
+      final result = await loadMore();
+
+      if (result != null && hasMore.value) {
+        pagingController.appendPage(result, nextPageKey.value);
+      } else if (result != null) {
+        pagingController.appendLastPage(result);
+      }
+    } catch (e) {
+      pagingController.error = e;
+    }
+  }
+
+  void _resetPagingController() {
+    pagingController.removePageRequestListener(_onPagingControllerRequest);
+    pagingController.nextPageKey = nextPageKey.value;
+    pagingController.itemList?.clear();
+  }
+
+  RxBool isBusy = false.obs;
+
+  RxList<Post> postList = RxList.empty(growable: true);
+  RxInt nextPageKey = 0.obs;
+  RxBool hasMore = true.obs;
+
+  Future<void> reloadAllOver() async {
+    nextPageKey.value = 0;
+    hasMore.value = true;
+    _resetPagingController();
+    final result = await loadMore();
+    if (result != null && hasMore.value) {
+      pagingController.appendPage(result, nextPageKey.value);
+    } else if (result != null) {
+      pagingController.appendLastPage(result);
+    }
+    _initPagingController();
+  }
+
+  Future<List<Post>?> loadMore() async {
+    final result = await _loadPosts(nextPageKey.value);
+
+    if (result != null && result.length >= 10) {
+      nextPageKey.value = nextPageKey.value + result.length;
+      hasMore.value = true;
+    } else if (result != null) {
+      nextPageKey.value = nextPageKey.value + result.length;
+      hasMore.value = false;
+    }
+
+    return result;
+  }
+
+  Future<List<Post>?> _loadPosts(int pageKey) async {
+    isBusy.value = true;
+
+    final PostProvider provider = Get.find();
+
+    Response resp;
+    try {
+      resp = await provider.listRecommendations(
+        pageKey,
+        channel: mode.value == 0 ? null : 'shuffle',
+      );
+    } catch (e) {
+      rethrow;
+    } finally {
+      isBusy.value = false;
+    }
+
+    final PaginationResult result = PaginationResult.fromJson(resp.body);
+    final out = result.data?.map((e) => Post.fromJson(e)).toList();
+
+    if (out != null) postList.addAll(out.cast<Post>());
+
+    return out;
+  }
+
+  void dispose() {
+    pagingController.dispose();
+  }
+}

lib/screens/home.dart

@@ -1,10 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:get/get.dart';
-import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
+import 'package:solian/controllers/post_list_controller.dart';
-import 'package:solian/models/pagination.dart';
-import 'package:solian/models/post.dart';
 import 'package:solian/providers/auth.dart';
-import 'package:solian/providers/content/posts.dart';
 import 'package:solian/router.dart';
 import 'package:solian/screens/account/notification.dart';
 import 'package:solian/theme.dart';
@@ -22,48 +19,21 @@ class HomeScreen extends StatefulWidget {
 
 class _HomeScreenState extends State<HomeScreen>
     with SingleTickerProviderStateMixin {
-  final PagingController<int, Post> _pagingController =
+  final PostListController _postController = PostListController();
-      PagingController(firstPageKey: 0);
 
   late final TabController _tabController;
 
-  int mode = 0;
-
-  getPosts(int pageKey) async {
-    final PostProvider provider = Get.find();
-
-    Response resp;
-    try {
-      resp = await provider.listRecommendations(
-        pageKey,
-        channel: mode == 0 ? null : 'shuffle',
-      );
-    } catch (e) {
-      _pagingController.error = e;
-      return;
-    }
-
-    final PaginationResult result = PaginationResult.fromJson(resp.body);
-    final parsed = result.data?.map((e) => Post.fromJson(e)).toList();
-    if (parsed != null && parsed.length >= 10) {
-      _pagingController.appendPage(parsed, pageKey + parsed.length);
-    } else if (parsed != null) {
-      _pagingController.appendLastPage(parsed);
-    }
-  }
-
   @override
   void initState() {
     super.initState();
-    _pagingController.addPageRequestListener(getPosts);
     _tabController = TabController(length: 2, vsync: this);
     _tabController.addListener(() {
       switch (_tabController.index) {
         case 0:
         case 1:
-          if (mode == _tabController.index) break;
+          if (_postController.mode.value == _tabController.index) break;
-          mode = _tabController.index;
+          _postController.mode.value = _tabController.index;
-          _pagingController.refresh();
+          _postController.reloadAllOver();
       }
     });
   }
@@ -84,11 +54,8 @@ class _HomeScreenState extends State<HomeScreen>
             );
           },
         ),
-        body: RefreshIndicator(
+        body: NestedScrollView(
-          onRefresh: () => Future.sync(() => _pagingController.refresh()),
+          headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
-          child: NestedScrollView(
-            headerSliverBuilder:
-                (BuildContext context, bool innerBoxIsScrolled) {
             return [
               SliverAppBar(
                 title: AppBarTitle('home'.tr),
@@ -116,23 +83,25 @@ class _HomeScreenState extends State<HomeScreen>
           body: TabBarView(
             controller: _tabController,
             children: [
-                CustomScrollView(slivers: [
+              RefreshIndicator(
-                  FeedListWidget(controller: _pagingController),
+                onRefresh: () => _postController.reloadAllOver(),
+                child: CustomScrollView(slivers: [
+                  FeedListWidget(controller: _postController.pagingController),
                 ]),
+              ),
               CustomScrollView(slivers: [
-                  FeedListWidget(controller: _pagingController),
+                FeedListWidget(controller: _postController.pagingController),
               ]),
             ],
           ),
         ),
       ),
-      ),
     );
   }
 
   @override
   void dispose() {
-    _pagingController.dispose();
+    _postController.dispose();
     super.dispose();
   }
 }

lib/screens/posts/post_editor.dart

@@ -105,7 +105,7 @@ class _PostPublishScreenState extends State<PostPublishScreen> {
   void syncWidget() {
     if (widget.edit != null) {
       _contentController.text = widget.edit!.body['content'];
-      _attachments = widget.edit!.body['attachments'] ?? List.empty();
+      _attachments = widget.edit!.body['attachments']?.cast<int>() ?? List.empty();
       _isDraft = widget.edit!.isDraft ?? false;
     }
   }

lib/translations/en_us.dart

@@ -95,7 +95,7 @@ const messagesEnglish = {
   'postEdited': 'Edited at @date',
   'postNewCreated': 'Created at @date',
   'postAttachmentTip': '@count attachment(s)',
-  'postInRealm': 'In realm @realm',
+  'postInRealm': 'In @realm',
   'postDetail': 'Post',
   'postReplies': 'Replies',
   'postPublish': 'Post a post',

lib/widgets/posts/post_item.dart

@@ -86,7 +86,7 @@ class _PostItemState extends State<PostItem> {
     }
     if (widget.item.realm != null) {
       labels.add('postInRealm'.trParams({
-        'realm': '#${widget.item.realm!.id}',
+        'realm': widget.item.realm!.alias,
       }));
     }