add unread indicator in backbutton

lib/src/back_button.dart

@@ -1,44 +1,57 @@
 import 'package:flutter/material.dart';
+import 'package:stream_chat_flutter/src/stream_icons.dart';
+import 'package:stream_chat_flutter/src/unread_indicator.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 
 class StreamBackButton extends StatelessWidget {
   const StreamBackButton({
     Key key,
     this.onPressed,
     this.icon = Icons.arrow_back_ios_outlined,
+    this.showUnreads = false,
   }) : super(key: key);
 
   final VoidCallback onPressed;
   final IconData icon;
+  final bool showUnreads;
 
   @override
   Widget build(BuildContext context) {
-    return Padding(
-      padding: const EdgeInsets.all(14.0),
-      child: RawMaterialButton(
-        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(4)),
-        elevation: 0,
-        highlightElevation: 0,
-        focusElevation: 0,
-        disabledElevation: 0,
-        hoverElevation: 0,
-        onPressed: () {
-          if (onPressed != null) {
-            onPressed();
-          } else {
-            Navigator.of(context).pop();
-          }
-        },
-        fillColor: Theme.of(context).brightness == Brightness.dark
-            ? Colors.white.withOpacity(.1)
-            : Colors.black.withOpacity(.1),
-        child: Icon(
-          icon ?? Icons.arrow_back_ios_outlined,
-          size: 15,
-          color: Theme.of(context).brightness == Brightness.dark
-              ? Colors.white
-              : Colors.black,
+    return Stack(
+      children: [
+        Padding(
+          padding: const EdgeInsets.all(14.0),
+          child: RawMaterialButton(
+            shape:
+                RoundedRectangleBorder(borderRadius: BorderRadius.circular(4)),
+            elevation: 0,
+            highlightElevation: 0,
+            focusElevation: 0,
+            disabledElevation: 0,
+            hoverElevation: 0,
+            onPressed: () {
+              if (onPressed != null) {
+                onPressed();
+              } else {
+                Navigator.of(context).pop();
+              }
+            },
+            child: Icon(
+              icon ?? StreamIcons.left,
+              size: 24,
+              color: Theme.of(context).brightness == Brightness.dark
+                  ? Colors.white
+                  : Colors.black,
+            ),
+          ),
         ),
-      ),
+        if (showUnreads)
+          Positioned(
+            top: 7,
+            right: 7,
+            child: UnreadIndicator(),
+          ),
+      ],
     );
   }
 }

lib/src/channel_header.dart

@@ -81,7 +81,10 @@ class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
       brightness: Theme.of(context).brightness,
       elevation: 1,
       leading: showBackButton
-          ? StreamBackButton(onPressed: onBackPressed)
+          ? StreamBackButton(
+              onPressed: onBackPressed,
+              showUnreads: true,
+            )
           : SizedBox(),
       backgroundColor:
           StreamChatTheme.of(context).channelTheme.channelHeaderTheme.color,

lib/src/channel_preview.dart

@@ -2,10 +2,10 @@ import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 import 'package:jiffy/jiffy.dart';
 import 'package:stream_chat/stream_chat.dart';
-import 'package:stream_chat_flutter/src/unread_indicator.dart';
 
 import '../stream_chat_flutter.dart';
 import 'channel_name.dart';
+import 'channel_unread_indicator.dart';
 
 /// ![screenshot](https://raw.githubusercontent.com/GetStream/stream-chat-flutter/master/screenshots/channel_preview.png)
 /// ![screenshot](https://raw.githubusercontent.com/GetStream/stream-chat-flutter/master/screenshots/channel_preview_paint.png)
@@ -80,7 +80,7 @@ class ChannelPreview extends StatelessWidget {
                                 e.user.id == channel.client.state.user.id)) {
                           return SizedBox();
                         }
-                        return UnreadIndicator(
+                        return ChannelUnreadIndicator(
                           channel: channel,
                         );
                       }),

lib/src/channel_unread_indicator.dart

@@ -0,0 +1,48 @@
+import 'package:flutter/material.dart';
+import 'package:stream_chat/stream_chat.dart';
+import 'package:stream_chat_flutter/src/stream_chat_theme.dart';
+
+class ChannelUnreadIndicator extends StatelessWidget {
+  const ChannelUnreadIndicator({
+    Key key,
+    @required this.channel,
+  }) : super(key: key);
+
+  final Channel channel;
+
+  @override
+  Widget build(BuildContext context) {
+    return StreamBuilder<int>(
+      stream: channel.state.unreadCountStream,
+      initialData: channel.state.unreadCount,
+      builder: (context, snapshot) {
+        if (!snapshot.hasData || snapshot.data == 0) {
+          return SizedBox();
+        }
+        return Material(
+          borderRadius: BorderRadius.circular(8),
+          color: StreamChatTheme.of(context)
+              .channelPreviewTheme
+              .unreadCounterColor,
+          child: Padding(
+            padding: const EdgeInsets.only(
+              left: 5.0,
+              right: 5.0,
+              top: 2,
+              bottom: 1,
+            ),
+            child: Center(
+              child: Text(
+                '${snapshot.data}',
+                style: TextStyle(
+                  fontSize: 11,
+                  color: Colors.white,
+                ),
+              ),
+            ),
+          ),
+        );
+      },
+    );
+  }
+}

lib/src/unread_indicator.dart

@@ -1,47 +1,46 @@
 import 'package:flutter/material.dart';
-import 'package:stream_chat/stream_chat.dart';
 import 'package:stream_chat_flutter/src/stream_chat_theme.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 
 class UnreadIndicator extends StatelessWidget {
   const UnreadIndicator({
     Key key,
-    @required this.channel,
   }) : super(key: key);
 
-  final Channel channel;
-
   @override
   Widget build(BuildContext context) {
+    final client = StreamChat.of(context).client;
     return StreamBuilder<int>(
-        stream: channel.state.unreadCountStream,
-        initialData: channel.state.unreadCount,
-        builder: (context, snapshot) {
-          if (!snapshot.hasData || snapshot.data == 0) {
-            return SizedBox();
-          }
-          return Material(
-            borderRadius: BorderRadius.circular(8),
-            color: StreamChatTheme.of(context)
-                .channelPreviewTheme
-                .unreadCounterColor,
-            child: Padding(
-              padding: const EdgeInsets.only(
-                left: 5.0,
-                right: 5.0,
-                top: 2,
-                bottom: 1,
-              ),
-              child: Center(
-                child: Text(
-                  '${snapshot.data}',
-                  style: TextStyle(
-                    fontSize: 11,
-                    color: Colors.white,
-                  ),
+      stream: client.state.totalUnreadCountStream,
+      initialData: client.state.totalUnreadCount,
+      builder: (context, snapshot) {
+        if (!snapshot.hasData || snapshot.data == 0) {
+          return SizedBox();
+        }
+        return Material(
+          borderRadius: BorderRadius.circular(8),
+          color: StreamChatTheme.of(context)
+              .channelPreviewTheme
+              .unreadCounterColor,
+          child: Padding(
+            padding: const EdgeInsets.only(
+              left: 5.0,
+              right: 5.0,
+              top: 2,
+              bottom: 1,
+            ),
+            child: Center(
+              child: Text(
+                '${snapshot.data}',
+                style: TextStyle(
+                  fontSize: 11,
+                  color: Colors.white,
                 ),
               ),
             ),
-          );
-        });
+          ),
+        );
+      },
+    );
   }
 }