[UI-Kit -> ChannelListCore] Replace ChannelListController function signature with AsyncCallback for better refreshIndicator support.

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

packages/stream_chat_flutter/lib/src/channel_list_view.dart

@@ -180,15 +180,13 @@ class _ChannelListViewState extends State<ChannelListView> {
 
     if (widget.pullToRefresh) {
       child = RefreshIndicator(
-        onRefresh: () async => _channelListController.loadData(),
+        onRefresh: () => _channelListController.loadData(),
         child: child,
       );
     }
 
     return LazyLoadScrollView(
-      onEndOfPage: () async {
-        _channelListController.paginateData();
-      },
+      onEndOfPage: () => _channelListController.paginateData(),
       child: child,
     );
   }
@@ -451,9 +449,7 @@ class _ChannelListViewState extends State<ChannelListView> {
             style: Theme.of(context).textTheme.headline6,
           ),
           FlatButton(
-            onPressed: () {
-              _channelListController.loadData();
-            },
+            onPressed: () => _channelListController.loadData(),
             child: Text('Retry'),
           ),
         ],

packages/stream_chat_flutter_core/lib/src/channel_list_core.dart

@@ -159,10 +159,9 @@ class _ChannelListCoreState extends State<ChannelListCore> {
     return widget.errorBuilder(context, snapshot.error);
   }
 
-  void loadData() {
+  Future<void> loadData() {
     final channelsBloc = ChannelsBloc.of(context);
-
-    channelsBloc.queryChannels(
+    return channelsBloc.queryChannels(
       filter: widget.filter,
       sortOptions: widget.sort,
       paginationParams: widget.pagination,
@@ -170,10 +169,9 @@ class _ChannelListCoreState extends State<ChannelListCore> {
     );
   }
 
-  void paginateData() {
+  Future<void> paginateData() {
     final channelsBloc = ChannelsBloc.of(context);
-
-    channelsBloc.queryChannels(
+    return channelsBloc.queryChannels(
       filter: widget.filter,
       sortOptions: widget.sort,
       paginationParams: widget.pagination.copyWith(
@@ -229,10 +227,10 @@ class _ChannelListCoreState extends State<ChannelListCore> {
 class ChannelListController {
   /// This function calls Stream's servers to load a list of channels. If there is existing data,
   /// calling this function causes a reload.
-  VoidCallback loadData;
+  AsyncCallback loadData;
 
   /// This function is used to load another page of data. Note, [loadData] should be
   /// used to populate the initial page of data. Calling [paginateData] performs a query
   /// to load subsequent pages.
-  VoidCallback paginateData;
+  AsyncCallback paginateData;
 }