Merge pull request #540 from GetStream/feat/channel-pagination-error-retry

fix: channel pagination error retry

packages/stream_chat_flutter/lib/src/channel_list_view.dart

@@ -202,6 +202,7 @@ class _ChannelListViewState extends State<ChannelListView> {
   final _slideController = SlidableController();
 
   late final _defaultController = ChannelListController();
+
   ChannelListController get _channelListController =>
       widget.channelListController ?? _defaultController;
 
@@ -237,11 +238,8 @@ class _ChannelListViewState extends State<ChannelListView> {
   }
 
   Widget _buildListView(BuildContext context, List<Channel> channels) {
-    late Widget child;
-
-    if (channels.isNotEmpty) {
     if (widget.crossAxisCount > 1) {
-        child = GridView.builder(
+      return GridView.builder(
         padding: widget.padding,
         gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
           crossAxisCount: widget.crossAxisCount,
@@ -251,12 +249,12 @@ class _ChannelListViewState extends State<ChannelListView> {
         itemBuilder: (context, index) =>
             _gridItemBuilder(context, index, channels),
       );
-      } else {
+    }
-        child = ListView.separated(
+    return ListView.separated(
       padding: widget.padding,
       physics: const AlwaysScrollableScrollPhysics(),
-          itemCount:
+      // all channels + progress loader
-              channels.isNotEmpty ? channels.length + 1 : channels.length,
+      itemCount: channels.length + 1,
       separatorBuilder: (_, index) {
         if (widget.separatorBuilder != null) {
           return widget.separatorBuilder!(context, index);
@@ -267,10 +265,6 @@ class _ChannelListViewState extends State<ChannelListView> {
           _listItemBuilder(context, index, channels),
     );
   }
-    }
-
-    return child;
-  }
 
   Widget _buildEmptyWidget(BuildContext context) => LayoutBuilder(
         builder: (context, viewportConstraints) {
@@ -486,11 +480,14 @@ class _ChannelListViewState extends State<ChannelListView> {
 
   Widget _listItemBuilder(BuildContext context, int i, List<Channel> channels) {
     final channelsBloc = ChannelsBloc.of(context);
+
+    if (i == channels.length) {
+      return _buildQueryProgressIndicator(context, channelsBloc);
+    }
+
     final onTap = _getChannelTap(context);
     final chatThemeData = StreamChatTheme.of(context);
     final backgroundColor = chatThemeData.colorTheme.inputBg;
-
-    if (i < channels.length) {
     final channel = channels[i];
 
     return StreamChannel(
@@ -588,9 +585,6 @@ class _ChannelListViewState extends State<ChannelListView> {
         ),
       ),
     );
-    } else {
-      return _buildQueryProgressIndicator(context, channelsBloc);
-    }
   }
 
   ChannelTapCallback _getChannelTap(BuildContext context) {
@@ -661,26 +655,31 @@ class _ChannelListViewState extends State<ChannelListView> {
       BetterStreamBuilder<bool>(
         stream: channelsProvider.queryChannelsLoading,
         initialData: false,
-          errorBuilder: (context, err) => Container(
+        errorBuilder: (context, err) {
-                color: StreamChatTheme.of(context)
+          final theme = StreamChatTheme.of(context);
-                    .colorTheme
+          return Container(
-                    .accentError
+            color: theme.colorTheme.textLowEmphasis.withOpacity(0.9),
-                    .withOpacity(.2),
+            child: Padding(
-                child: const Padding(
+              padding: const EdgeInsets.all(16),
-                  padding: EdgeInsets.symmetric(vertical: 16),
+              child: Text(
-                  child: Center(
+                'Error loading channels',
-                    child: Text('Error loading channels'),
+                style: theme.textTheme.body.copyWith(
+                  color: Colors.white,
                 ),
               ),
             ),
-          builder: (context, data) => data
+          );
-              ? const Center(
+        },
+        builder: (context, showLoading) {
+          if (!showLoading) return const Offstage();
+          return const Center(
             child: Padding(
               padding: EdgeInsets.all(16),
               child: CircularProgressIndicator(),
             ),
-                )
+          );
-              : const Offstage());
+        },
+      );
 
   Widget _separatorBuilder(context, i) {
     final effect = StreamChatTheme.of(context).colorTheme.borderBottom;

packages/stream_chat_flutter_core/lib/src/channels_bloc.dart

@@ -146,6 +146,8 @@ class ChannelsBlocState extends State<ChannelsBloc>
         _paginationEnded = true;
       }
     } catch (e, stk) {
+      // reset loading controller
+      _queryChannelsLoadingController.sink.add(false);
       if (_channelsController.hasValue) {
         _queryChannelsLoadingController.addError(e, stk);
       } else {

packages/stream_chat_flutter_core/lib/src/lazy_load_scroll_view.dart

@@ -85,6 +85,7 @@ class _LazyLoadScrollViewState extends State<LazyLoadScrollView> {
       final extentBefore = notification.metrics.extentBefore;
       final extentAfter = notification.metrics.extentAfter;
       final scrollingDown = _scrollPosition < pixels;
+      _scrollPosition = pixels;
 
       if (scrollingDown) {
         if (extentAfter <= scrollOffset) {
@@ -97,8 +98,6 @@ class _LazyLoadScrollViewState extends State<LazyLoadScrollView> {
           return true;
         }
       }
-
-      _scrollPosition = pixels;
     }
     if (notification is OverscrollNotification) {
       if (notification.overscroll > 0) {

packages/stream_chat_flutter_core/lib/src/message_search_bloc.dart

@@ -98,6 +98,8 @@ class MessageSearchBlocState extends State<MessageSearchBloc>
         _queryMessagesLoadingController.add(false);
       }
     } catch (e, stk) {
+      // reset loading controller
+      _queryMessagesLoadingController.add(false);
       if (_messageResponses.hasValue) {
         _queryMessagesLoadingController.addError(e, stk);
       } else {

packages/stream_chat_flutter_core/lib/src/users_bloc.dart

@@ -96,6 +96,8 @@ class UsersBlocState extends State<UsersBloc>
         _queryUsersLoadingController.add(false);
       }
     } catch (e, stk) {
+      // reset loading controller
+      _queryUsersLoadingController.add(false);
       if (_usersController.hasValue) {
         _queryUsersLoadingController.addError(e, stk);
       } else {