show error on channel loading

lib/src/channel_list_view.dart

@@ -125,7 +125,7 @@ class _ChannelListViewState extends State<ChannelListView> {
                 return widget.errorBuilder(snapshot.error);
               }
 
-              String message = snapshot.error.toString();
+              var message = snapshot.error.toString();
               if (snapshot.error is DioError) {
                 final dioError = snapshot.error as DioError;
                 if (dioError.type == DioErrorType.RESPONSE) {
@@ -287,6 +287,17 @@ class _ChannelListViewState extends State<ChannelListView> {
         stream: streamChat.queryChannelsLoading,
         initialData: false,
         builder: (context, snapshot) {
+          if (snapshot.hasError) {
+            return Container(
+              color: Color(0xffd0021B).withAlpha(26),
+              child: Padding(
+                padding: const EdgeInsets.symmetric(vertical: 16.0),
+                child: Center(
+                  child: Text('Error loading messages'),
+                ),
+              ),
+            );
+          }
           return Container(
             height: 100,
             padding: EdgeInsets.all(32),

lib/src/channel_preview.dart

@@ -118,7 +118,7 @@ class ChannelPreview extends StatelessWidget {
           return SizedBox();
         }
 
-        String text = lastMessage.text;
+        var text = lastMessage.text;
         if (lastMessage.isDeleted) {
           text = 'This message was deleted.';
         } else if (lastMessage.attachments != null) {

lib/src/message_widget.dart

@@ -95,7 +95,7 @@ class _MessageWidgetState extends State<MessageWidget>
     final alignment =
         _isMyMessage ? Alignment.centerRight : Alignment.centerLeft;
 
-    List<Widget> row = <Widget>[
+    var row = List<Widget>.from([
       Column(
         crossAxisAlignment:
             _isMyMessage ? CrossAxisAlignment.end : CrossAxisAlignment.start,
@@ -113,7 +113,7 @@ class _MessageWidgetState extends State<MessageWidget>
               width: 40,
             )
           : _buildUserAvatar(),
-    ];
+    ]);
 
     if (!_isMyMessage) {
       row = row.reversed.toList();
@@ -309,7 +309,7 @@ class _MessageWidgetState extends State<MessageWidget>
             []);
 
     if (widget.message.text.trim().isNotEmpty) {
-      String text = widget.message.text;
+      var text = widget.message.text;
       text = _replaceMentions(text);
 
       column.addAll(

lib/src/stream_chat.dart

@@ -197,20 +197,23 @@ class StreamChatState extends State<StreamChat> {
     PaginationParams paginationParams,
     Map<String, dynamic> options,
   }) async {
-    if (_queryChannelsLoadingController.value) {
+    if (_queryChannelsLoadingController.value == true) {
       return;
     }
     _queryChannelsLoadingController.sink.add(true);
 
     try {
-      widget.client.queryChannels(
+      await widget.client.queryChannels(
         filter: filter,
         sort: sortOptions,
         options: options,
         paginationParams: paginationParams,
       );
-    } finally {
       _queryChannelsLoadingController.sink.add(false);
+    } catch (err, stackTrace) {
+      _queryChannelsLoadingController.addError(err, stackTrace);
+    } finally {
+//      _queryChannelsLoadingController.sink.add(false);
     }
   }