fix message and user list core controller setup

packages/stream_chat_flutter_core/lib/src/message_search_list_core.dart

@@ -114,15 +114,22 @@ class MessageSearchListCoreState extends State<MessageSearchListCore> {
     if (newMessageSearchBloc != _messageSearchBloc) {
       _messageSearchBloc = newMessageSearchBloc;
       loadData();
-      if (widget.messageSearchListController != null) {
-        widget.messageSearchListController!.loadData = loadData;
-        widget.messageSearchListController!.paginateData = paginateData;
-      }
     }
 
     super.didChangeDependencies();
   }
 
+  void _setupController() {
+    widget.messageSearchListController!.loadData = loadData;
+    widget.messageSearchListController!.paginateData = paginateData;
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    _setupController();
+  }
+
   @override
   Widget build(BuildContext context) => _buildListView(_messageSearchBloc!);
 
@@ -176,6 +183,11 @@ class MessageSearchListCoreState extends State<MessageSearchListCore> {
             oldWidget.paginationParams?.toJson().toString()) {
       loadData();
     }
+
+    if (widget.messageSearchListController !=
+        oldWidget.messageSearchListController) {
+      _setupController();
+    }
   }
 }
 

packages/stream_chat_flutter_core/lib/src/user_list_core.dart

@@ -128,14 +128,21 @@ class UserListCoreState extends State<UserListCore>
     if (newUsersBloc != _usersBloc) {
       _usersBloc = newUsersBloc;
       loadData();
-      if (widget.userListController != null) {
-        widget.userListController!.loadData = loadData;
-        widget.userListController!.paginateData = paginateData;
-      }
     }
     super.didChangeDependencies();
   }
 
+  @override
+  void initState() {
+    super.initState();
+    _setupController();
+  }
+
+  void _setupController() {
+    widget.userListController!.loadData = loadData;
+    widget.userListController!.paginateData = paginateData;
+  }
+
   @override
   Widget build(BuildContext context) => _buildListView();
 
@@ -212,6 +219,10 @@ class UserListCoreState extends State<UserListCore>
             oldWidget.pagination?.toJson().toString()) {
       loadData();
     }
+
+    if (widget.userListController != oldWidget.userListController) {
+      _setupController();
+    }
   }
 }