Add custom sort support for offline channels

Signed-off-by: Sahil Kumar <[email protected]>

packages/stream_chat_flutter_core/lib/src/channel_list_core.dart

@@ -106,7 +106,7 @@ class ChannelListCore extends StatefulWidget {
   /// Sorting is based on field and direction, multiple sorting options can be provided.
   /// You can sort based on last_updated, last_message_at, updated_at, created_at or member_count.
   /// Direction can be ascending or descending.
-  final List<SortOption> sort;
+  final List<SortOption<ChannelModel>> sort;
 
   /// Pagination parameters
   /// limit: the number of channels to return (max is 30)
@@ -118,8 +118,7 @@ class ChannelListCore extends StatefulWidget {
   _ChannelListCoreState createState() => _ChannelListCoreState();
 }
 
-class _ChannelListCoreState extends State<ChannelListCore>
-    with WidgetsBindingObserver {
+class _ChannelListCoreState extends State<ChannelListCore> {
   @override
   Widget build(BuildContext context) {
     final channelsBloc = ChannelsBloc.of(context);
@@ -133,34 +132,21 @@ class _ChannelListCoreState extends State<ChannelListCore>
     return StreamBuilder<List<Channel>>(
       stream: channelsBlocState.channelsStream,
       builder: (context, snapshot) {
-        var child;
         if (snapshot.hasError) {
-          child = _buildErrorWidget(
-            snapshot,
-            context,
-            channelsBlocState,
-          );
-        } else if (!snapshot.hasData) {
-          child = _buildLoadingWidget();
-        } else {
-          final channels = snapshot.data;
-
-          child = widget.emptyBuilder(context);
-
-          if (channels.isNotEmpty) {
-            return widget.listBuilder(context, channels);
-          }
+          return _buildErrorWidget(snapshot, context, channelsBlocState);
         }
-
-        return child;
+        if (!snapshot.hasData) {
+          return widget.loadingBuilder(context);
+        }
+        final channels = snapshot.data;
+        if (channels.isEmpty) {
+          return widget.emptyBuilder(context);
+        }
+        return widget.listBuilder(context, channels);
       },
     );
   }
 
-  Widget _buildLoadingWidget() {
-    return widget.loadingBuilder(context);
-  }
-
   Widget _buildErrorWidget(
     AsyncSnapshot<List<Channel>> snapshot,
     BuildContext context,
@@ -197,39 +183,21 @@ class _ChannelListCoreState extends State<ChannelListCore>
     );
   }
 
-  StreamSubscription _subscription;
+  StreamSubscription<Event> _subscription;
 
   @override
   void initState() {
     super.initState();
-
-    WidgetsBinding.instance.addObserver(this);
-
-    final channelsBloc = ChannelsBloc.of(context);
-    channelsBloc.queryChannels(
-      filter: widget.filter,
-      sortOptions: widget.sort,
-      paginationParams: widget.pagination,
-      options: widget.options,
-    );
-
+    loadData();
     final client = StreamChatCore.of(context).client;
-
     _subscription = client
         .on(
-      EventType.connectionRecovered,
-      EventType.notificationAddedToChannel,
-      EventType.notificationMessageNew,
-      EventType.channelVisible,
-    )
-        .listen((event) {
-      channelsBloc.queryChannels(
-        filter: widget.filter,
-        sortOptions: widget.sort,
-        paginationParams: widget.pagination,
-        options: widget.options,
-      );
-    });
+          EventType.connectionRecovered,
+          EventType.notificationAddedToChannel,
+          EventType.notificationMessageNew,
+          EventType.channelVisible,
+        )
+        .listen((event) => loadData());
 
     if (widget.channelListController != null) {
       widget.channelListController.loadData = loadData;
@@ -246,20 +214,13 @@ class _ChannelListCoreState extends State<ChannelListCore>
         widget.pagination?.toJson()?.toString() !=
             oldWidget.pagination?.toJson()?.toString() ||
         widget.options?.toString() != oldWidget.options?.toString()) {
-      final channelsBloc = ChannelsBloc.of(context);
-      channelsBloc.queryChannels(
-        filter: widget.filter,
-        sortOptions: widget.sort,
-        paginationParams: widget.pagination,
-        options: widget.options,
-      );
+      loadData();
     }
   }
 
   @override
   void dispose() {
     _subscription.cancel();
-    WidgetsBinding.instance.removeObserver(this);
     super.dispose();
   }
 }

packages/stream_chat_flutter_core/lib/src/channels_bloc.dart

@@ -84,7 +84,7 @@ class ChannelsBlocState extends State<ChannelsBloc>
   /// Calls [client.queryChannels] updating [queryChannelsLoading] stream
   Future<void> queryChannels({
     Map<String, dynamic> filter,
-    List<SortOption> sortOptions,
+    List<SortOption<ChannelModel>> sortOptions,
     PaginationParams paginationParams,
     Map<String, dynamic> options,
     bool onlyOffline = false,
@@ -102,21 +102,21 @@ class ChannelsBlocState extends State<ChannelsBloc>
           paginationParams.offset == null ||
           paginationParams.offset == 0;
       final oldChannels = List<Channel>.from(channels ?? []);
-      final _channels = await client.queryChannels(
+      await for (final channels in client.queryChannels(
         filter: filter,
         sort: sortOptions,
         options: options,
         paginationParams: paginationParams,
-        onlyOffline: onlyOffline,
-      );
-
-      if (clear) {
-        _channelsController.add(_channels);
-      } else {
-        final l = oldChannels + _channels;
-        _channelsController.add(l);
+        preferOffline: onlyOffline,
+      )) {
+        if (clear) {
+          _channelsController.add(channels);
+        } else {
+          final l = oldChannels + channels;
+          _channelsController.add(l);
+        }
+        _queryChannelsLoadingController.sink.add(false);
       }
-      _queryChannelsLoadingController.sink.add(false);
     } catch (err, stackTrace) {
       print(err);
       print(stackTrace);