Merge pull request #113 from GetStream/feature-header

Date header

lib/src/message_list_view.dart

@@ -6,6 +6,7 @@ import 'package:stream_chat/stream_chat.dart';
 import 'package:stream_chat_flutter/src/message_widget.dart';
 import 'package:stream_chat_flutter/src/system_message.dart';
 import 'package:visibility_detector/visibility_detector.dart';
+import 'package:widgets_visibility_provider/widgets_visibility_provider.dart';
 
 import '../stream_chat_flutter.dart';
 import 'date_divider.dart';
@@ -155,11 +156,15 @@ class _MessageListViewState extends State<MessageListView> {
     final streamChannel = StreamChannel.of(context);
 
     /// TODO: find a better solution when (https://github.com/flutter/flutter/issues/21023) is fixed
-    return Stack(
+    return WidgetsVisibilityProvider(
+      condition: (c) => null,
+      child: Stack(
+        alignment: Alignment.center,
         children: [
           NotificationListener<ScrollNotification>(
             onNotification: (_) {
-            if (_scrollController.offset < 150 && _newMessageList.isNotEmpty) {
+              if (_scrollController.offset < 150 &&
+                  _newMessageList.isNotEmpty) {
                 setState(() {
                   _messages.insertAll(0, _newMessageList);
                   _newMessageList.clear();
@@ -188,7 +193,8 @@ class _MessageListViewState extends State<MessageListView> {
                           children: <Widget>[
                             buildParentMessage(widget.parentMessage),
                             Padding(
-                            padding: const EdgeInsets.symmetric(horizontal: 32),
+                              padding:
+                                  const EdgeInsets.symmetric(horizontal: 32),
                               child: Container(
                                 padding: const EdgeInsets.all(8),
                                 child: Text(
@@ -251,7 +257,9 @@ class _MessageListViewState extends State<MessageListView> {
                   if (nextMessage != null &&
                       !Jiffy(message.createdAt.toLocal())
                           .isSame(nextMessage.createdAt.toLocal(), Units.DAY)) {
-                  return Column(
+                    return VisibleNotifierWidget(
+                      data: i,
+                      child: Column(
                         crossAxisAlignment: CrossAxisAlignment.stretch,
                         children: <Widget>[
                           messageWidget,
@@ -265,10 +273,14 @@ class _MessageListViewState extends State<MessageListView> {
                                   ),
                           ),
                         ],
+                      ),
                     );
                   }
 
-                return messageWidget;
+                  return VisibleNotifierWidget(
+                    child: messageWidget,
+                    data: i,
+                  );
                 },
                 childCount: _messages.length + 2,
                 findChildIndexCallback: (key) {
@@ -292,7 +304,23 @@ class _MessageListViewState extends State<MessageListView> {
                   }
                   return _buildScrollToBottom(streamChannel);
                 }),
+          Positioned(
+            top: 20.0,
+            child: WidgetsVisibilityConsumer(
+              listener: (context, event,) {},
+              builder: (context, event) {
+                if(event.positionDataList == null || event.positionDataList.isEmpty) {
+                  return Container();
+                }
+
+                return DateDivider(
+                  dateTime: _messages[event.positionDataList.last.data].createdAt.toLocal(),
+                );
+              },
+            ),
+          ),
         ],
+      ),
     );
   }
 

pubspec.yaml

@@ -30,6 +30,7 @@ dependencies:
   flutter_slidable: ^0.5.4
   carousel_slider: ^2.2.1
   clipboard: ^0.1.2+8
+  widgets_visibility_provider: ^2.0.2
 
 flutter:
   fonts: