changes

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

example/lib/choose_user_page.dart

@@ -13,13 +13,13 @@ import 'routes/routes.dart';
 const kStreamApiKey = 'STREAM_API_KEY';
 const kStreamUserId = 'STREAM_USER_ID';
 const kStreamToken = 'STREAM_TOKEN';
-const kDefaultStreamApiKey = 'uj7qrdbfrzvg';
+const kDefaultStreamApiKey = 's2dxdhpxd94g';
 
 class ChooseUserPage extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final users = <String, User>{
-      'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VyX2lkIjoidmlzaGFsIn0.lCz-idDgaZ-xszjnuB_hTfeIOhTFmJtTB2fEjhwrcCI':
+      'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VyX2lkIjoidmlzaGFsIn0._JHWzo92fpTWZMZriJHXqOng6ShYVmWrdaIaPwEPKBg':
           User(
         id: 'vishal',
         extraData: {

example/lib/group_chat_details_screen.dart

@@ -133,7 +133,7 @@ class _GroupChatDetailsScreenState extends State<GroupChatDetailsScreen> {
                           context,
                           Routes.CHANNEL_PAGE,
                           ModalRoute.withName(Routes.HOME),
-                          arguments: channel,
+                          arguments: ChannelPageArgs(channel: channel),
                         );
                       },
               ),

example/lib/main.dart

@@ -337,40 +337,14 @@ class _ChannelListPageState extends State<ChannelListPage> {
                               final message = messageResponse.message;
                               final channel = Channel.fromState(
                                 client,
-                                ChannelState(
+                                ChannelState(channel: messageResponse.channel),
-                                  channel: messageResponse.channel,
-                                  messages: [message],
-                                ),
                               );
-                              await Future.wait([
-                                channel.query(
-                                  messagesPagination: PaginationParams(
-                                    lessThan: message.id,
-                                    limit: 25,
-                                  ),
-                                  preferOffline: true,
-                                ),
-                                channel.query(
-                                  messagesPagination: PaginationParams(
-                                    greaterThan: message.id,
-                                    limit: 25,
-                                  ),
-                                  preferOffline: true,
-                                ),
-                              ]);
-                              final messages = channel.state.messages;
-                              final totalMessages = messages.length;
-                              final messageIndex = messages
-                                  .indexWhere((e) => e.id == message.id);
-                              final initialIndex = totalMessages - messageIndex;
-                              final bool isFirstMessage = messageIndex == 0;
                               Navigator.pushNamed(
                                 context,
                                 Routes.CHANNEL_PAGE,
                                 arguments: ChannelPageArgs(
                                   channel: channel,
-                                  initialScrollIndex: initialIndex,
+                                  initialMessage: message,
-                                  initialAlignment: isFirstMessage ? 0 : 0.5,
                                 ),
                               );
                             },
@@ -406,24 +380,24 @@ class _ChannelListPageState extends State<ChannelListPage> {
 
 class ChannelPageArgs {
   final Channel channel;
-  final int initialScrollIndex;
+  final Message initialMessage;
-  final double initialAlignment;
 
   const ChannelPageArgs({
     this.channel,
-    this.initialScrollIndex = 0,
+    this.initialMessage,
-    this.initialAlignment = 0,
   });
 }
 
 class ChannelPage extends StatelessWidget {
   final int initialScrollIndex;
   final double initialAlignment;
+  final bool highlightInitialMessage;
 
   const ChannelPage({
     Key key,
-    this.initialScrollIndex = 0,
+    this.initialScrollIndex,
-    this.initialAlignment = 0,
+    this.initialAlignment,
+    this.highlightInitialMessage = false,
   }) : super(key: key);
 
   @override
@@ -441,6 +415,7 @@ class ChannelPage extends StatelessWidget {
                 MessageListView(
                   initialScrollIndex: initialScrollIndex,
                   initialAlignment: initialAlignment,
+                  highlightInitialMessage: highlightInitialMessage,
                   threadBuilder: (_, parentMessage) {
                     return ThreadPage(
                       parent: parentMessage,
@@ -481,8 +456,8 @@ class ThreadPage extends StatelessWidget {
   ThreadPage({
     Key key,
     this.parent,
-    this.initialScrollIndex = 0,
+    this.initialScrollIndex,
-    this.initialAlignment = 0,
+    this.initialAlignment,
   }) : super(key: key);
 
   @override

example/lib/new_chat_screen.dart

@@ -339,7 +339,7 @@ class _NewChatScreenState extends State<NewChatScreen> {
       context,
       Routes.CHANNEL_PAGE,
       ModalRoute.withName(Routes.HOME),
-      arguments: channel,
+      arguments: ChannelPageArgs(channel: channel),
     );
   }
 }

example/lib/routes/app_routes.dart

@@ -37,9 +37,9 @@ class AppRoutes {
               final arg = args as ChannelPageArgs;
               return StreamChannel(
                 channel: arg.channel,
+                initialMessageId: arg.initialMessage?.id,
                 child: ChannelPage(
-                  initialScrollIndex: arg.initialScrollIndex,
+                  highlightInitialMessage: arg.initialMessage != null,
-                  initialAlignment: arg.initialAlignment,
                 ),
               );
             });

lib/src/lazy_load_scroll_view.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 enum _LoadingStatus { LOADING, STABLE }
@@ -9,10 +10,10 @@ class LazyLoadScrollView extends StatefulWidget {
   final Widget child;
 
   /// Called when the [child] reaches the start of the list
-  final VoidCallback onStartOfPage;
+  final AsyncCallback onStartOfPage;
 
   /// Called when the [child] reaches the end of the list
-  final VoidCallback onEndOfPage;
+  final AsyncCallback onEndOfPage;
 
   /// The offset to take into account when triggering [onEndOfPage] in pixels
   final double scrollOffset;
@@ -38,14 +39,6 @@ class LazyLoadScrollView extends StatefulWidget {
 class _LazyLoadScrollViewState extends State<LazyLoadScrollView> {
   _LoadingStatus _loadMoreStatus = _LoadingStatus.STABLE;
 
-  @override
-  void didUpdateWidget(LazyLoadScrollView oldWidget) {
-    super.didUpdateWidget(oldWidget);
-    if (!widget.isLoading) {
-      _loadMoreStatus = _LoadingStatus.STABLE;
-    }
-  }
-
   @override
   Widget build(BuildContext context) {
     return NotificationListener(
@@ -62,7 +55,11 @@ class _LazyLoadScrollViewState extends State<LazyLoadScrollView> {
         if (_loadMoreStatus != null &&
             _loadMoreStatus == _LoadingStatus.STABLE) {
           _loadMoreStatus = _LoadingStatus.LOADING;
-          widget.onEndOfPage();
+          if (widget.onEndOfPage != null) {
+            widget.onEndOfPage().whenComplete(() {
+              _loadMoreStatus = _LoadingStatus.STABLE;
+            });
+          }
         }
       }
       if (notification.metrics.minScrollExtent < notification.metrics.pixels &&
@@ -71,7 +68,11 @@ class _LazyLoadScrollViewState extends State<LazyLoadScrollView> {
         if (_loadMoreStatus != null &&
             _loadMoreStatus == _LoadingStatus.STABLE) {
           _loadMoreStatus = _LoadingStatus.LOADING;
-          widget.onStartOfPage();
+          if (widget.onStartOfPage != null) {
+            widget.onStartOfPage().whenComplete(() {
+              _loadMoreStatus = _LoadingStatus.STABLE;
+            });
+          }
         }
       }
       return true;
@@ -81,14 +82,22 @@ class _LazyLoadScrollViewState extends State<LazyLoadScrollView> {
         if (_loadMoreStatus != null &&
             _loadMoreStatus == _LoadingStatus.STABLE) {
           _loadMoreStatus = _LoadingStatus.LOADING;
-          widget.onEndOfPage();
+          if (widget.onEndOfPage != null) {
+            widget.onEndOfPage().whenComplete(() {
+              _loadMoreStatus = _LoadingStatus.STABLE;
+            });
+          }
         }
       }
       if (notification.overscroll < 0) {
         if (_loadMoreStatus != null &&
             _loadMoreStatus == _LoadingStatus.STABLE) {
           _loadMoreStatus = _LoadingStatus.LOADING;
-          widget.onStartOfPage();
+          if (widget.onStartOfPage != null) {
+            widget.onStartOfPage().whenComplete(() {
+              _loadMoreStatus = _LoadingStatus.STABLE;
+            });
+          }
         }
       }
       return true;

lib/src/message_input.dart

@@ -21,7 +21,6 @@ import 'package:stream_chat_flutter/src/stream_svg_icon.dart';
 import 'package:stream_chat_flutter/src/user_avatar.dart';
 import 'package:substring_highlight/substring_highlight.dart';
 import 'package:video_compress/video_compress.dart';
-import 'package:photo_manager/photo_manager.dart';
 
 import '../stream_chat_flutter.dart';
 import 'stream_channel.dart';
@@ -436,6 +435,7 @@ class MessageInputState extends State<MessageInput> {
   }
 
   Timer _debounce;
+
   void _onChanged(BuildContext context, String s) {
     if (_debounce?.isActive == true) _debounce.cancel();
     _debounce = Timer(
@@ -1859,7 +1859,8 @@ class MessageInputState extends State<MessageInput> {
     _mentionsOverlay?.remove();
     _mentionsOverlay = null;
 
-    final channel = StreamChannel.of(context).channel;
+    final streamChannel = StreamChannel.of(context);
+    final channel = streamChannel.channel;
 
     Future sendingFuture;
     Message message;
@@ -1885,6 +1886,10 @@ class MessageInputState extends State<MessageInput> {
       message = await widget.preMessageSending(message);
     }
 
+    if (!channel.state.isUpToDate) {
+      await streamChannel.reloadChannel();
+    }
+
     if (widget.editMessage == null ||
         widget.editMessage.status == MessageSendingStatus.FAILED) {
       sendingFuture = channel.sendMessage(message);
@@ -1970,6 +1975,7 @@ class MessageInputState extends State<MessageInput> {
   }
 
   bool _initialized = false;
+
   @override
   void didChangeDependencies() {
     if (widget.editMessage != null && !_initialized) {

lib/src/message_list_view.dart

@@ -1,8 +1,10 @@
 import 'dart:async';
 import 'dart:math';
 
+import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:jiffy/jiffy.dart';
+import 'package:rxdart/rxdart.dart';
 import 'package:scrollable_positioned_list/scrollable_positioned_list.dart';
 import 'package:stream_chat/stream_chat.dart';
 import 'package:stream_chat_flutter/src/lazy_load_scroll_view.dart';
@@ -109,10 +111,11 @@ class MessageListView extends StatefulWidget {
     this.onThreadTap,
     this.dateDividerBuilder,
     this.scrollPhysics = const AlwaysScrollableScrollPhysics(),
-    this.initialScrollIndex = 0,
+    this.initialScrollIndex,
-    this.initialAlignment = 0,
+    this.initialAlignment,
     this.scrollController,
     this.itemPositionListener,
+    this.highlightInitialMessage = false,
   }) : super(key: key);
 
   /// Function used to build a custom message widget
@@ -154,6 +157,11 @@ class MessageListView extends StatefulWidget {
   /// The ScrollPhysics used by the ListView
   final ScrollPhysics scrollPhysics;
 
+  /// If true the list will highlight the initialMessage if there is any.
+  ///
+  /// Also See [StreamChannel]
+  final bool highlightInitialMessage;
+
   @override
   _MessageListViewState createState() => _MessageListViewState();
 }
@@ -166,6 +174,51 @@ class _MessageListViewState extends State<MessageListView> {
   ItemPositionsListener _itemPositionListener;
   int _messageListLength;
 
+  int get _initialIndex {
+    if (widget.initialScrollIndex != null) return widget.initialScrollIndex;
+    final streamChannel = StreamChannel.of(context);
+    if (streamChannel.initialMessageId != null) {
+      final messages = streamChannel.channel.state.messages;
+      final totalMessages = messages.length;
+      final messageIndex = messages.indexWhere((e) {
+        return e.id == streamChannel.initialMessageId;
+      });
+      return totalMessages - messageIndex - 1;
+    }
+    return 0;
+  }
+
+  double get _initialAlignment {
+    if (widget.initialAlignment != null) return widget.initialAlignment;
+    final streamChannel = StreamChannel.of(context);
+    if (streamChannel.initialMessageId != null) {
+      final messages = streamChannel.channel.state.messages;
+      final messageIndex = messages.indexWhere((e) {
+        return e.id == streamChannel.initialMessageId;
+      });
+      final isFirstMessage = messageIndex == 0;
+      return isFirstMessage ? 0 : 0.5;
+    }
+    return 0;
+  }
+
+  bool _isInitialMessage(String id) {
+    final streamChannel = StreamChannel.of(context);
+    return streamChannel.initialMessageId == id;
+  }
+
+  bool get _upToDate => StreamChannel.of(context).channel.state.isUpToDate;
+
+  bool _topPaginationActive = false;
+  bool _bottomPaginationActive = false;
+
+  bool get _paginationActive => _topPaginationActive || _bottomPaginationActive;
+
+  int initialIndex;
+  double initialAlignment;
+
+  List<Message> messages = <Message>[];
+
   @override
   Widget build(BuildContext context) {
     final streamChannel = StreamChannel.of(context);
@@ -176,6 +229,11 @@ class _MessageListViewState extends State<MessageListView> {
             .map((threads) => threads[widget.parentMessage.id])
         : streamChannel.channel.state.messagesStream;
 
+    if (!_paginationActive && !_upToDate) {
+      initialIndex = _initialIndex;
+      initialAlignment = _initialAlignment;
+    }
+
     return StreamBuilder<List<Message>>(
         stream: messagesStream.map((messages) => messages
             .where((e) =>
@@ -190,9 +248,10 @@ class _MessageListViewState extends State<MessageListView> {
             );
           }
 
-          final messages = snapshot.data?.reversed?.toList() ?? [];
+          final messageList = snapshot.data?.reversed?.toList() ?? [];
 
-          if (messages.isEmpty) {
+          if (messageList.isEmpty) {
+            if (_upToDate) {
               return Center(
                 child: Text(
                   'No chats here yet...',
@@ -203,20 +262,27 @@ class _MessageListViewState extends State<MessageListView> {
                 ),
               );
             }
+          } else {
+            messages = messageList;
+          }
 
           final newMessagesListLength = messages.length;
 
+          if (_bottomPaginationActive) {
             if (_itemPositionListener.itemPositions.value?.isNotEmpty == true &&
                 _messageListLength != null) {
               final first = _itemPositionListener.itemPositions.value.first;
               final diff = newMessagesListLength - _messageListLength;
               if (diff > 0) {
-              _scrollController.jumpTo(
+                initialIndex = first.index + diff;
-                index: first.index + diff,
+                initialAlignment = first.itemLeadingEdge;
-                alignment: first.itemLeadingEdge,
-              );
               }
             }
+          } else if (!_topPaginationActive && _upToDate) {
+            // Reset the index in-case we send any new message
+            initialIndex = 0;
+            initialAlignment = 0;
+          }
 
           _messageListLength = newMessagesListLength;
 
@@ -224,28 +290,32 @@ class _MessageListViewState extends State<MessageListView> {
             alignment: Alignment.center,
             children: [
               LazyLoadScrollView(
-                onStartOfPage: () => _paginateData(
+                onStartOfPage: () async {
-                  streamChannel,
+                  if (!_upToDate) {
-                  QueryDirection.bottom,
+                    _topPaginationActive = false;
-                ),
+                    _bottomPaginationActive = true;
-                onEndOfPage: () => _paginateData(
+                    _paginateData(streamChannel, QueryDirection.bottom);
-                  streamChannel,
+                  }
-                  QueryDirection.top,
+                },
-                ),
+                onEndOfPage: () async {
+                  _topPaginationActive = true;
+                  _bottomPaginationActive = false;
+                  _paginateData(streamChannel, QueryDirection.top);
+                },
                 child: ScrollablePositionedList.builder(
+                  key: ValueKey(initialIndex + initialAlignment),
                   itemPositionsListener: _itemPositionListener,
                   addAutomaticKeepAlives: true,
-                  key: Key('messageListView'),
+                  initialScrollIndex: initialIndex ?? 0,
-                  initialScrollIndex: widget.initialScrollIndex,
+                  initialAlignment: initialAlignment ?? 0,
-                  initialAlignment: widget.initialAlignment,
                   physics: widget.scrollPhysics,
                   itemScrollController: _scrollController,
                   reverse: true,
                   itemCount: messages.length +
-                      1 +
+                      2 +
                       (widget.parentMessage != null ? 1 : 0),
                   itemBuilder: (context, i) {
-                    if (i == messages.length + 1) {
+                    if (i == messages.length + 2) {
                       if (widget.parentMessageBuilder != null) {
                         return widget.parentMessageBuilder(
                           context,
@@ -273,16 +343,24 @@ class _MessageListViewState extends State<MessageListView> {
                         );
                       }
                     }
-
+                    if (i == messages.length + 1) {
-                    if (i == messages.length) {
+                      return _buildLoadingIndicator(
-                      return _buildLoadingIndicator(streamChannel);
+                        streamChannel,
+                        QueryDirection.top,
+                      );
                     }
-                    final message = messages[i];
+                    if (i == 0) {
-                    final nextMessage = i > 0 ? messages[i - 1] : null;
+                      return _buildLoadingIndicator(
+                        streamChannel,
+                        QueryDirection.bottom,
+                      );
+                    }
+                    final message = messages[i - 1];
+                    final nextMessage = (i - 1) > 0 ? messages[i - 2] : null;
 
                     Widget messageWidget;
 
-                    if (i == 0) {
+                    if (i == 1) {
                       messageWidget = _buildBottomMessage(
                         context,
                         message,
@@ -339,8 +417,7 @@ class _MessageListViewState extends State<MessageListView> {
                   },
                 ),
               ),
-              if (widget.showScrollToBottom && _showScrollToBottom)
+              if (widget.showScrollToBottom) _buildScrollToBottom(),
-                _buildScrollToBottom(),
               Positioned(
                 top: 20.0,
                 child: ValueListenableBuilder<Iterable<ItemPosition>>(
@@ -380,7 +457,7 @@ class _MessageListViewState extends State<MessageListView> {
     if (widget.parentMessage == null) {
       channel.queryMessages(direction: direction);
     } else {
-      channel.getReplies(widget.parentMessage.id, direction: direction);
+      channel.getReplies(widget.parentMessage.id);
     }
   }
 
@@ -393,6 +470,27 @@ class _MessageListViewState extends State<MessageListView> {
 
   Widget _buildScrollToBottom() {
     final streamChannel = StreamChannel.of(context);
+    return StreamBuilder<Tuple2<bool, int>>(
+      stream: Rx.combineLatest2(
+        streamChannel.channel.state.isUpToDateStream,
+        streamChannel.channel.state.unreadCountStream,
+        (bool isUpToDate, int unreadCount) => Tuple2(isUpToDate, unreadCount),
+      ),
+      builder: (_, snapshot) {
+        if (snapshot.hasError) {
+          return Offstage();
+        } else if (!snapshot.hasData) {
+          return Offstage();
+        }
+        final isUpToDate = snapshot.data.item1;
+        final showScrollToBottom = !isUpToDate || _showScrollToBottom;
+        if (!showScrollToBottom) {
+          return Offstage();
+        }
+        final unreadCount = snapshot.data.item2;
+        final showUnreadCount = unreadCount > 0 &&
+            streamChannel.channel.state.members.any(
+                (e) => e.userId == streamChannel.channel.client.state.user.id);
         return Positioned(
           bottom: 8,
           right: 8,
@@ -407,26 +505,22 @@ class _MessageListViewState extends State<MessageListView> {
                   color: Colors.black,
                 ),
                 onPressed: () {
-              setState(() {
+                  if (!_upToDate) {
-                _showScrollToBottom = false;
+                    _bottomPaginationActive = false;
-              });
+                    _topPaginationActive = false;
+                    streamChannel.reloadChannel();
+                  } else {
+                    setState(() => _showScrollToBottom = false);
                     _scrollController.scrollTo(
                       index: 0,
                       duration: Duration(seconds: 1),
                       curve: Curves.easeInOut,
                     );
+                  }
                 },
               ),
-          if (streamChannel.channel.state.members.any((Member e) =>
+              if (showUnreadCount)
-              e.userId == streamChannel.channel.client.state.user.id))
+                Positioned(
-            StreamBuilder<int>(
-                stream: streamChannel.channel.state.unreadCountStream,
-                initialData: streamChannel.channel.state.unreadCount,
-                builder: (context, snapshot) {
-                  if (!snapshot.hasData || snapshot.data <= 0) {
-                    return Offstage();
-                  }
-                  return Positioned(
                   width: 20,
                   height: 20,
                   left: 10,
@@ -443,20 +537,24 @@ class _MessageListViewState extends State<MessageListView> {
                       ),
                     ),
                   ),
-                  );
+                ),
-                }),
             ],
           ),
         );
+      },
+    );
   }
 
-  Container _buildLoadingIndicator(StreamChannelState streamChannel) {
+  Widget _buildLoadingIndicator(
-    return Container(
+    StreamChannelState streamChannel,
+    QueryDirection direction,
+  ) {
+    final stream = direction == QueryDirection.top
+        ? streamChannel.queryTopMessages
+        : streamChannel.queryBottomMessages;
+    return StreamBuilder<bool>(
         key: Key('LOADING-INDICATOR'),
-      height: 50,
+        stream: stream,
-      width: double.infinity,
-      child: StreamBuilder<bool>(
-          stream: streamChannel.queryMessage,
         initialData: false,
         builder: (context, snapshot) {
           if (snapshot.hasError) {
@@ -468,16 +566,21 @@ class _MessageListViewState extends State<MessageListView> {
             );
           }
           if (!snapshot.data) {
-              return SizedBox();
+            if (direction == QueryDirection.top) {
+              return Container(
+                height: 50,
+                width: double.infinity,
+              );
+            }
+            return Offstage();
           }
           return Center(
             child: Padding(
               padding: const EdgeInsets.all(8.0),
-                child: CircularProgressIndicator(),
+              child: const CupertinoActivityIndicator(),
             ),
           );
-          }),
+        });
-    );
   }
 
   Widget _buildTopMessage(
@@ -544,9 +647,7 @@ class _MessageListViewState extends State<MessageListView> {
           _bottomWasVisible = !isVisible;
         }
         if (mounted) {
-          setState(() {
+          setState(() => _showScrollToBottom = !isVisible);
-            _showScrollToBottom = !isVisible;
-          });
         }
       },
       child: messageWidget,
@@ -602,7 +703,7 @@ class _MessageListViewState extends State<MessageListView> {
     final userId = StreamChat.of(context).user.id;
     final isMyMessage = message.user.id == userId;
     final isNextUser =
-        index - 1 >= 0 && message.user.id == messages[index - 1]?.user?.id;
+        index - 2 >= 0 && message.user.id == messages[index - 2]?.user?.id;
 
     final channel = StreamChannel.of(context).channel;
     final readList = channel.state?.read
@@ -673,24 +774,12 @@ class _MessageListViewState extends State<MessageListView> {
 
     _messageNewListener =
         streamChannel.channel.on(EventType.messageNew).listen((event) {
-      final firstElementInViewport =
-          _itemPositionListener.itemPositions.value.first;
       if (event.message.user.id == streamChannel.channel.client.state.user.id) {
         WidgetsBinding.instance.addPostFrameCallback((_) {
           _scrollController.jumpTo(
             index: 0,
           );
         });
-      } else {
-        if (firstElementInViewport.index != 0) {
-          _scrollController.jumpTo(
-            index: firstElementInViewport.index + 1,
-            alignment: firstElementInViewport.itemLeadingEdge,
-          );
-        }
-      }
-      if (firstElementInViewport.index == 0) {
-        streamChannel.channel.markRead();
       }
     });
 

lib/src/stream_channel.dart

@@ -10,19 +10,23 @@ enum QueryDirection { top, bottom }
 ///
 /// Use [StreamChannel.of] to get the current [StreamChannelState] instance.
 class StreamChannel extends StatefulWidget {
-  StreamChannel({
+  const StreamChannel({
     Key key,
     @required this.child,
     @required this.channel,
     this.showLoading = true,
-  }) : super(
+    this.initialMessageId,
-          key: key,
+  })  : assert(child != null),
-        );
+        assert(channel != null),
+        super(key: key);
 
   final Widget child;
   final Channel channel;
   final bool showLoading;
 
+  /// If passed the channel will load from this particular message.
+  final String initialMessageId;
+
   /// Use this method to get the current [StreamChannelState] instance
   static StreamChannelState of(BuildContext context) {
     StreamChannelState streamChannelState;
@@ -45,135 +49,123 @@ class StreamChannelState extends State<StreamChannel> {
   /// Current channel
   Channel get channel => widget.channel;
 
+  /// InitialMessageId
+  String get initialMessageId => widget.initialMessageId;
+
   /// Current channel state stream
   Stream<ChannelState> get channelStateStream =>
       widget.channel.state.channelStateStream;
 
-  final BehaviorSubject<bool> _queryMessageController = BehaviorSubject();
+  final _queryTopMessagesController = BehaviorSubject.seeded(false);
+  final _queryBottomMessagesController = BehaviorSubject.seeded(false);
 
-  /// The stream notifying the state of queryMessage call
+  /// The stream notifying the state of [_queryTopMessages] call
-  Stream<bool> get queryMessage => _queryMessageController.stream;
+  Stream<bool> get queryTopMessages => _queryTopMessagesController.stream;
+
+  /// The stream notifying the state of [_queryBottomMessages] call
+  Stream<bool> get queryBottomMessages => _queryBottomMessagesController.stream;
 
   bool _topPaginationEnded = false;
   bool _bottomPaginationEnded = false;
 
-  /// Calls [channel.query] updating [queryMessage] stream
+  Future<void> _queryTopMessages({
-  void queryMessages({QueryDirection direction = QueryDirection.top}) {
+    int limit = 20,
-    if (_queryMessageController.value == true ||
+    bool preferOffline = false,
-        (_topPaginationEnded && _bottomPaginationEnded)) {
+  }) async {
+    if (_topPaginationEnded || _queryTopMessagesController?.value == true) {
       return;
     }
+    _queryTopMessagesController.add(true);
 
-    _queryMessageController.add(true);
+    if (channel.state.messages.isEmpty) {
-
+      return _queryTopMessagesController.add(false);
-    String id;
-    PaginationParams params;
-
-    final messageLimit = 25;
-
-    if (channel.state.messages.isNotEmpty) {
-      switch (direction) {
-        case QueryDirection.top:
-          id = channel.state.messages.first.id;
-          params = PaginationParams(
-            lessThan: id,
-            limit: messageLimit,
-          );
-          break;
-        case QueryDirection.bottom:
-          id = channel.state.messages.last.id;
-          params = PaginationParams(
-            greaterThan: id,
-            limit: messageLimit,
-          );
-          break;
-      }
     }
 
-    widget.channel
+    final oldestMessage = channel.state.messages.first;
-        .query(
+
-      messagesPagination: params,
+    try {
-      preferOffline: true,
+      final state = await queryBeforeMessage(
-    )
+        oldestMessage.id,
-        .then((res) {
+        limit: limit,
-      if (res.messages.isEmpty || res.messages.length < messageLimit) {
+        preferOffline: preferOffline,
-        switch (direction) {
+      );
-          case QueryDirection.top:
+      if (state.messages.isEmpty || state.messages.length < limit) {
         _topPaginationEnded = true;
-            break;
+      }
-          case QueryDirection.bottom:
+      _queryTopMessagesController.add(false);
+    } catch (e, stk) {
+      _queryTopMessagesController.addError(e, stk);
+    }
+  }
+
+  Future<void> _queryBottomMessages({
+    int limit = 20,
+    bool preferOffline = false,
+  }) async {
+    if (_bottomPaginationEnded ||
+        _queryBottomMessagesController?.value == true ||
+        channel?.state?.isUpToDate == true) return;
+    _queryBottomMessagesController.add(true);
+
+    if (channel.state.messages.isEmpty) {
+      return _queryBottomMessagesController.add(false);
+    }
+
+    final recentMessage = channel.state.messages.last;
+
+    try {
+      final state = await queryAfterMessage(
+        recentMessage.id,
+        limit: limit,
+        preferOffline: preferOffline,
+      );
+      if (state.messages.isEmpty || state.messages.length < limit) {
         _bottomPaginationEnded = true;
-            break;
+      }
+      _queryBottomMessagesController.add(false);
+    } catch (e, stk) {
+      _queryBottomMessagesController.addError(e, stk);
     }
   }
-      _queryMessageController.add(false);
+
-    }).catchError((e, stack) {
+  /// Calls [channel.query] updating [queryMessage] stream
-      if (!_queryMessageController.isClosed) {
+  Future<void> queryMessages({QueryDirection direction = QueryDirection.top}) {
-        _queryMessageController.addError(e, stack);
+    if (direction == QueryDirection.top) return _queryTopMessages();
-      }
+    return _queryBottomMessages();
-    });
   }
 
   /// Calls [channel.getReplies] updating [queryMessage] stream
   Future<void> getReplies(
     String parentId, {
-    QueryDirection direction = QueryDirection.top,
+    int limit = 50,
+    bool preferOffline = false,
   }) async {
-    if (_queryMessageController.value == true ||
+    if (_topPaginationEnded || _queryTopMessagesController.value) return;
-        (_topPaginationEnded && _bottomPaginationEnded)) {
+    _queryTopMessagesController.add(true);
-      return;
+
+    if (!channel.state.threads.containsKey(parentId)) {
+      return _queryTopMessagesController.add(false);
     }
 
-    _queryMessageController.add(true);
+    final thread = channel.state.threads[parentId];
 
-    String id;
+    if (thread.isEmpty) return _queryTopMessagesController.add(false);
-    PaginationParams params;
 
-    final messageLimit = 50;
+    final message = thread.first;
 
-    if (widget.channel.state.threads.containsKey(parentId)) {
+    try {
-      final thread = widget.channel.state.threads[parentId];
+      final state = await queryBeforeMessage(
-      if (thread != null && thread.isNotEmpty) {
+        message.id,
-        switch (direction) {
+        limit: limit,
-          case QueryDirection.top:
+        preferOffline: preferOffline,
-            id = thread?.first?.id;
-            params = PaginationParams(
-              lessThan: id,
-              limit: messageLimit,
       );
-            break;
+      if (state.messages.isEmpty || state.messages.length < limit) {
-          case QueryDirection.bottom:
-            id = thread?.last?.id;
-            params = PaginationParams(
-              greaterThan: id,
-              limit: messageLimit,
-            );
-            break;
-        }
-      }
-    }
-
-    return widget.channel
-        .getReplies(
-      parentId,
-      params,
-      preferOffline: true,
-    )
-        .then((res) {
-      if (res.messages.isEmpty || res.messages.length < messageLimit) {
-        switch (direction) {
-          case QueryDirection.top:
         _topPaginationEnded = true;
-            break;
-          case QueryDirection.bottom:
-            _bottomPaginationEnded = true;
-            break;
       }
+      _queryTopMessagesController.add(false);
+    } catch (e, stk) {
+      _queryTopMessagesController.addError(e, stk);
     }
-      _queryMessageController.add(false);
-    }).catchError((e, stack) {
-      _queryMessageController.addError(e, stack);
-    });
   }
 
   /// Query the channel members and watchers
@@ -190,41 +182,148 @@ class StreamChannelState extends State<StreamChannel> {
     );
   }
 
+  /// Loads channel at specific message
+  Future<void> loadChannelAtMessage(
+    String messageId, {
+    int before = 20,
+    int after = 20,
+    bool preferOffline = false,
+  }) {
+    return queryAtMessage(
+      messageId: messageId,
+      before: before,
+      after: after,
+      preferOffline: preferOffline,
+    );
+  }
+
+  ///
+  Future<void> queryAtMessage({
+    String messageId,
+    int before = 20,
+    int after = 20,
+    bool preferOffline = false,
+  }) async {
+    if (channel.state == null) return;
+    channel.state.isUpToDate = false;
+    channel.state.truncate();
+
+    if (messageId == null) {
+      await channel.query(
+        messagesPagination: PaginationParams(
+          limit: before,
+        ),
+        preferOffline: preferOffline,
+      );
+      channel.state.isUpToDate = true;
+      return;
+    }
+
+    return Future.wait([
+      queryBeforeMessage(
+        messageId,
+        limit: before,
+        preferOffline: preferOffline,
+      ),
+      queryAfterMessage(
+        messageId,
+        limit: after,
+        preferOffline: preferOffline,
+      ),
+    ]);
+  }
+
+  ///
+  Future<ChannelState> queryBeforeMessage(
+    String messageId, {
+    int limit = 20,
+    bool preferOffline = false,
+  }) {
+    return channel.query(
+      messagesPagination: PaginationParams(
+        lessThan: messageId,
+        limit: limit,
+      ),
+      preferOffline: preferOffline,
+    );
+  }
+
+  ///
+  Future<ChannelState> queryAfterMessage(
+    String messageId, {
+    int limit = 20,
+    bool preferOffline = false,
+  }) async {
+    final state = await channel.query(
+      messagesPagination: PaginationParams(
+        greaterThanOrEqual: messageId,
+        limit: limit,
+      ),
+      preferOffline: preferOffline,
+    );
+    if (state.messages.isEmpty || state.messages.length < limit) {
+      channel.state.isUpToDate = true;
+    }
+    return state;
+  }
+
+  /// Reloads the channel with latest message
+  Future<void> reloadChannel() => queryAtMessage(before: 30);
+
+  List<Future<bool>> _futures;
+
+  Future<bool> get _loadChannelAtMessage async {
+    try {
+      await loadChannelAtMessage(initialMessageId);
+      return true;
+    } catch (e, stk) {
+      print('Error: $e\nStack: $stk');
+      rethrow;
+    }
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    _futures = [widget.channel.initialized];
+    if (initialMessageId != null) {
+      _futures.add(_loadChannelAtMessage);
+    }
+  }
+
   @override
   void dispose() {
-    _queryMessageController.close();
+    _queryTopMessagesController.close();
+    _queryBottomMessagesController.close();
     super.dispose();
   }
 
   @override
   Widget build(BuildContext context) {
-    if (widget.channel == null) {
+    Widget child = FutureBuilder<List<bool>>(
+      future: Future.wait(_futures),
+      initialData: [
+        channel.state != null,
+        if (initialMessageId != null) false,
+      ],
+      builder: (context, snapshot) {
+        final initialized = snapshot.data[0];
+        final dataLoaded = initialMessageId == null ? true : snapshot.data[1];
+        if (widget.showLoading && (!initialized || !dataLoaded)) {
           return Center(
             child: CircularProgressIndicator(),
           );
-    }
-    return FutureBuilder<bool>(
-      future: widget.channel.initialized,
-      initialData: widget.channel.state != null,
-      builder: (context, snapshot) {
-        if (widget.showLoading && (!snapshot.hasData || !snapshot.data)) {
-          return Container(
-            height: 30,
-            child: Center(
-              child: CircularProgressIndicator(),
-            ),
-          );
         } else if (snapshot.hasError) {
-          return Container(
+          return Center(
-            height: 30,
-            child: Center(
             child: Text(snapshot.error),
-            ),
           );
-        } else {
-          return widget.child;
         }
+        return widget.child;
       },
     );
+    if (initialMessageId != null) {
+      child = Material(child: child);
+    }
+    return child;
   }
 }

lib/src/user_list_view.dart

@@ -339,7 +339,9 @@ class _UserListViewState extends State<UserListView>
               );
 
         return LazyLoadScrollView(
-          onEndOfPage: () => _listenUserPagination(usersBlocState),
+          onEndOfPage: () async {
+            return _listenUserPagination(usersBlocState);
+          },
           child: child,
         );
       },

pubspec.yaml

@@ -29,9 +29,10 @@ dependencies:
   image_picker: ^0.6.7+2
   flutter_keyboard_visibility: ^3.3.0
   stream_chat:
-    git:
+    path: ../stream-chat-dart
-      url: https://github.com/GetStream/stream-chat-dart
+#    git:
-      ref: two-way-pagination
+#      url: https://github.com/GetStream/stream-chat-dart
+#      ref: two-way-pagination
   mime: ^0.9.6+3
   video_compress: ^2.1.1
   visibility_detector: ^0.1.5