lint changes

packages/stream_chat_flutter/lib/src/back_button.dart

@@ -1,10 +1,12 @@
 import 'package:flutter/material.dart';
 import 'package:stream_chat_flutter/src/stream_svg_icon.dart';
 import 'package:stream_chat_flutter/src/unread_indicator.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 
-import '../stream_chat_flutter.dart';
+/// Back button implementation
-
 class StreamBackButton extends StatelessWidget {
+
+  /// Constructor for creating back button
   const StreamBackButton({
     Key? key,
     this.onPressed,
@@ -12,15 +14,17 @@ class StreamBackButton extends StatelessWidget {
     this.cid,
   }) : super(key: key);
 
+  /// Callback for when button is pressed
   final VoidCallback? onPressed;
+
+  /// Show unread count
   final bool showUnreads;
 
   /// Channel cid used to retrieve unread count
   final String? cid;
 
   @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context) => Stack(
-    return Stack(
       alignment: Alignment.center,
       children: [
         RawMaterialButton(
@@ -55,4 +59,3 @@ class StreamBackButton extends StatelessWidget {
       ],
     );
 }
-}

packages/stream_chat_flutter/lib/src/channel_bottom_sheet.dart

@@ -1,13 +1,14 @@
 import 'package:flutter/material.dart';
+import 'package:stream_chat_flutter/src/channel_info.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 
-import '../stream_chat_flutter.dart';
+/// Bottom Sheet with options
-import 'channel_info.dart';
-import 'option_list_tile.dart';
-
 class ChannelBottomSheet extends StatefulWidget {
-  final VoidCallback? onViewInfoTap;
+  /// Constructor for creating bottom sheet
+  const ChannelBottomSheet({Key? key, this.onViewInfoTap}) : super(key: key);
 
-  const ChannelBottomSheet({this.onViewInfoTap});
+  /// Callback when 'View Info' is tapped
+  final VoidCallback? onViewInfoTap;
 
   @override
   _ChannelBottomSheetState createState() => _ChannelBottomSheetState();
@@ -29,7 +30,7 @@ class _ChannelBottomSheetState extends State<ChannelBottomSheet> {
     return Material(
       color: StreamChatTheme.of(context).colorTheme.white,
       clipBehavior: Clip.antiAlias,
-      shape: RoundedRectangleBorder(
+      shape: const RoundedRectangleBorder(
         borderRadius: BorderRadius.only(
           topLeft: Radius.circular(16),
           topRight: Radius.circular(16),
@@ -120,7 +121,7 @@ class _ChannelBottomSheetState extends State<ChannelBottomSheet> {
                               ),
                               borderRadius: BorderRadius.circular(32),
                               onlineIndicatorConstraints:
-                                  BoxConstraints.tight(Size(12, 12)),
+                                  BoxConstraints.tight(const Size(12, 12)),
                             ),
                             const SizedBox(
                               height: 6,

packages/stream_chat_flutter/lib/src/channel_header.dart

@@ -4,13 +4,9 @@ import 'package:stream_chat_flutter/src/channel_info.dart';
 import 'package:stream_chat_flutter/src/channel_name.dart';
 import 'package:stream_chat_flutter/src/info_tile.dart';
 import 'package:stream_chat_flutter/src/stream_chat_theme.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
 
-import './channel_name.dart';
-import '../stream_chat_flutter.dart';
-import 'channel_image.dart';
-import 'connection_status_builder.dart';
-
 /// ![screenshot](https://raw.githubusercontent.com/GetStream/stream-chat-flutter/master/screenshots/channel_header.png)
 /// ![screenshot](https://raw.githubusercontent.com/GetStream/stream-chat-flutter/master/screenshots/channel_header_paint.png)
 ///
@@ -43,16 +39,36 @@ import 'connection_status_builder.dart';
 /// Usually you would use this widget as an [AppBar] inside a [Scaffold].
 /// However you can also use it as a normal widget.
 ///
-/// Make sure to have a [StreamChannel] ancestor in order to provide the information about the channel.
+/// Make sure to have a [StreamChannel] ancestor in order to provide the
-/// Every part of the widget uses a [StreamBuilder] to render the channel information as soon as it updates.
+/// information about the channel.
+/// Every part of the widget uses a [StreamBuilder] to render the channel
+/// information as soon as it updates.
 ///
 /// By default the widget shows a backButton that calls [Navigator.pop].
-/// You can disable this button using the [showBackButton] property of just override the behaviour
+/// You can disable this button using the [showBackButton] property of just
+/// override the behaviour
 /// with [onBackPressed].
 ///
-/// The widget components render the ui based on the first ancestor of type [StreamChatTheme] and on its [ChannelTheme.channelHeaderTheme] property.
+/// The widget components render the ui based on the first ancestor of type
+/// [StreamChatTheme] and on its [ChannelTheme.channelHeaderTheme] property.
 /// Modify it to change the widget appearance.
 class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
+  /// Creates a channel header
+  const ChannelHeader({
+    Key? key,
+    this.showBackButton = true,
+    this.onBackPressed,
+    this.onTitleTap,
+    this.showTypingIndicator = true,
+    this.onImageTap,
+    this.showConnectionStateTile = false,
+    this.title,
+    this.subtitle,
+    this.leading,
+    this.actions,
+  })  : preferredSize = const Size.fromHeight(kToolbarHeight),
+        super(key: key);
+
   /// True if this header shows the leading back button
   final bool showBackButton;
 
@@ -69,6 +85,7 @@ class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
   /// If true the typing indicator will be rendered if a user is typing
   final bool showTypingIndicator;
 
+  /// Show connection tile on header
   final bool showConnectionStateTile;
 
   /// Title widget
@@ -84,22 +101,6 @@ class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
   /// By default it shows the [ChannelImage]
   final List<Widget>? actions;
 
-  /// Creates a channel header
-  ChannelHeader({
-    Key? key,
-    this.showBackButton = true,
-    this.onBackPressed,
-    this.onTitleTap,
-    this.showTypingIndicator = true,
-    this.onImageTap,
-    this.showConnectionStateTile = false,
-    this.title,
-    this.subtitle,
-    this.leading,
-    this.actions,
-  })  : preferredSize = Size.fromHeight(kToolbarHeight),
-        super(key: key);
-
   @override
   Widget build(BuildContext context) {
     final channel = StreamChannel.of(context).channel;
@@ -110,7 +111,7 @@ class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
                 onPressed: onBackPressed,
                 showUnreads: true,
               )
-            : SizedBox());
+            : const SizedBox());
 
     return ConnectionStatusBuilder(
       statusBuilder: (context, status) {
@@ -131,6 +132,7 @@ class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
         }
 
         return InfoTile(
+          // ignore: avoid_bool_literals_in_conditional_expressions
           showMessage: showConnectionStateTile ? showStatus : false,
           message: statusString,
           child: AppBar(
@@ -165,7 +167,7 @@ class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
             centerTitle: true,
             title: InkWell(
               onTap: onTitleTap,
-              child: Container(
+              child: SizedBox(
                 height: preferredSize.height,
                 width: preferredSize.width,
                 child: Column(
@@ -178,7 +180,7 @@ class ChannelHeader extends StatelessWidget implements PreferredSizeWidget {
                               .channelHeaderTheme
                               .title,
                         ),
-                    SizedBox(height: 2),
+                    const SizedBox(height: 2),
                     subtitle ??
                         ChannelInfo(
                           showTypingIndicator: showTypingIndicator,

packages/stream_chat_flutter/lib/src/channel_image.dart

@@ -36,12 +36,14 @@ import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
 /// }
 /// ```
 ///
-/// The widget uses a [StreamBuilder] to render the channel information image as soon as it updates.
+/// The widget uses a [StreamBuilder] to render the channel information
+/// image as soon as it updates.
 ///
 /// By default the widget radius size is 40x40 pixels.
 /// Set the property [constraints] to set a custom dimension.
 ///
-/// The widget renders the ui based on the first ancestor of type [StreamChatTheme].
+/// The widget renders the ui based on the first ancestor of type
+/// [StreamChatTheme].
 /// Modify it to change the widget appearance.
 class ChannelImage extends StatelessWidget {
   /// Instantiate a new ChannelImage
@@ -56,6 +58,7 @@ class ChannelImage extends StatelessWidget {
     this.selectionThickness = 4,
   }) : super(key: key);
 
+  /// [BorderRadius] to display the widget
   final BorderRadius? borderRadius;
 
   /// The channel to show the image of
@@ -67,10 +70,13 @@ class ChannelImage extends StatelessWidget {
   /// The function called when the image is tapped
   final VoidCallback? onTap;
 
+  /// If image is selected
   final bool selected;
 
+  /// Selection color for image
   final Color? selectionColor;
 
+  /// Thickness of selection image
   final double selectionThickness;
 
   @override
@@ -91,8 +97,7 @@ class ChannelImage extends StatelessWidget {
               stream: streamChat.client.state.usersStream.map(
                   (users) => users[otherMember?.userId] ?? otherMember!.user!),
               initialData: otherMember!.user,
-              builder: (context, snapshot) {
+              builder: (context, snapshot) => UserAvatar(
-                return UserAvatar(
                   borderRadius: borderRadius ??
                       StreamChatTheme.of(context)
                           .channelPreviewTheme
@@ -109,14 +114,14 @@ class ChannelImage extends StatelessWidget {
                   selectionColor: selectionColor ??
                       StreamChatTheme.of(context).colorTheme.accentBlue,
                   selectionThickness: selectionThickness,
-                );
+                ));
-              });
         } else {
           final images = channel.state?.members
               .where((member) =>
                   member.user?.id != streamChat.user?.id &&
                   member.user?.extraData['image'] != null)
               .take(4)
+              // ignore: cast_nullable_to_non_nullable
               .map((e) => e.user?.extraData['image'] as String)
               .toList();
           return GroupImage(
@@ -161,8 +166,7 @@ class ChannelImage extends StatelessWidget {
                 if (image != null)
                   CachedNetworkImage(
                     imageUrl: image,
-                    errorWidget: (_, __, ___) {
+                    errorWidget: (_, __, ___) => Center(
-                      return Center(
                         child: Text(
                           snapshot.data?.containsKey('name') ?? false
                               ? snapshot.data!['name'][0]
@@ -172,8 +176,7 @@ class ChannelImage extends StatelessWidget {
                             fontWeight: FontWeight.bold,
                           ),
                         ),
-                      );
+                      ),
-                    },
                     fit: BoxFit.cover,
                   )
                 else

packages/stream_chat_flutter/lib/src/channel_info.dart

@@ -6,6 +6,14 @@ import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 import 'connection_status_builder.dart';
 
 class ChannelInfo extends StatelessWidget {
+  const ChannelInfo({
+    Key? key,
+    required this.channel,
+    this.textStyle,
+    this.showTypingIndicator = true,
+  }) : super(key: key);
+
+  /// The channel about which the info is to be displayed
   final Channel channel;
 
   /// The style of the text displayed
@@ -14,13 +22,6 @@ class ChannelInfo extends StatelessWidget {
   /// If true the typing indicator will be rendered if a user is typing
   final bool showTypingIndicator;
 
-  const ChannelInfo({
-    Key? key,
-    required this.channel,
-    this.textStyle,
-    this.showTypingIndicator = true,
-  }) : super(key: key);
-
   @override
   Widget build(BuildContext context) {
     final client = StreamChat.of(context).client;
@@ -93,10 +94,10 @@ class ChannelInfo extends StatelessWidget {
   Widget _buildConnectingTitleState(BuildContext context) => Row(
         mainAxisAlignment: MainAxisAlignment.center,
         children: [
-          Container(
+          const SizedBox(
             height: 16,
             width: 16,
-            child: const Center(
+            child: Center(
               child: CircularProgressIndicator(),
             ),
           ),

packages/stream_chat_flutter/lib/src/channel_list_header.dart

@@ -6,10 +6,7 @@ import 'package:stream_chat_flutter/src/stream_neumorphic_button.dart';
 import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
 
-import 'connection_status_builder.dart';
+/// Widget builder for title
-import 'info_tile.dart';
-import 'stream_chat.dart';
-
 typedef TitleBuilder = Widget Function(
   BuildContext context,
   ConnectionStatus status,
@@ -42,10 +39,13 @@ typedef TitleBuilder = Widget Function(
 /// Usually you would use this widget as an [AppBar] inside a [Scaffold].
 /// However you can also use it as a normal widget.
 ///
-/// The widget by default uses the inherited [StreamChatClient] to fetch information about the status.
+/// The widget by default uses the inherited [StreamChatClient]
-/// However you can also pass your own [StreamChatClient] if you don't have it in the widget tree.
+/// to fetch information about the status.
+/// However you can also pass your own [StreamChatClient]
+/// if you don't have it in the widget tree.
 ///
-/// The widget components render the ui based on the first ancestor of type [StreamChatTheme] and on its [ChannelListHeaderTheme] property.
+/// The widget components render the ui based on the first ancestor of type
+/// [StreamChatTheme] and on its [ChannelListHeaderTheme] property.
 /// Modify it to change the widget appearance.
 class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
   /// Instantiates a ChannelListHeader
@@ -75,8 +75,10 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
   /// Callback to call when pressing the new chat button.
   final VoidCallback? onNewChatButtonTap;
 
+  /// Show connection state tile
   final bool showConnectionStateTile;
 
+  /// Callback before navigation is performed
   final VoidCallback? preNavigationCallback;
 
   /// Subtitle widget
@@ -113,6 +115,7 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
         }
 
         return InfoTile(
+          // ignore: avoid_bool_literals_in_conditional_expressions
           showMessage: showConnectionStateTile ? showStatus : false,
           message: statusString,
           child: AppBar(
@@ -143,7 +146,7 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
                               .avatarTheme
                               ?.constraints,
                         )
-                      : Offstage(),
+                      : const Offstage(),
                 ),
             actions: actions ??
                 [
@@ -151,7 +154,7 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
                     child: IconButton(
                       icon: ConnectionStatusBuilder(
                         statusBuilder: (context, status) {
-                          var color;
+                          Color? color;
                           switch (status) {
                             case ConnectionStatus.connected:
                               color = StreamChatTheme.of(context)
@@ -193,11 +196,11 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
                       case ConnectionStatus.disconnected:
                         return _buildDisconnectedTitleState(context, _client);
                       default:
-                        return Offstage();
+                        return const Offstage();
                     }
                   },
                 ),
-                subtitle ?? Offstage(),
+                subtitle ?? const Offstage(),
               ],
             ),
           ),
@@ -213,18 +216,17 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
             ),
       );
 
-  Widget _buildConnectingTitleState(BuildContext context) {
+  Widget _buildConnectingTitleState(BuildContext context) => Row(
-    return Row(
       mainAxisAlignment: MainAxisAlignment.center,
       children: [
-        Container(
+        const SizedBox(
           height: 16,
           width: 16,
           child: Center(
             child: CircularProgressIndicator(),
           ),
         ),
-        SizedBox(width: 10),
+        const SizedBox(width: 10),
         Text(
           'Searching for Network',
           style: StreamChatTheme.of(context)
@@ -237,13 +239,11 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
         ),
       ],
     );
-  }
 
   Widget _buildDisconnectedTitleState(
     BuildContext context,
     StreamChatClient client,
-  ) {
+  ) => Row(
-    return Row(
       mainAxisAlignment: MainAxisAlignment.center,
       children: [
         Text(
@@ -275,8 +275,7 @@ class ChannelListHeader extends StatelessWidget implements PreferredSizeWidget {
         ),
       ],
     );
-  }
 
   @override
-  Size get preferredSize => Size.fromHeight(kToolbarHeight);
+  Size get preferredSize => const Size.fromHeight(kToolbarHeight);
 }

packages/stream_chat_flutter/lib/src/channel_list_view.dart

@@ -3,13 +3,12 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_slidable/flutter_slidable.dart';
 import 'package:shimmer/shimmer.dart';
+import 'package:stream_chat_flutter/src/channel_bottom_sheet.dart';
 import 'package:stream_chat_flutter/src/stream_svg_icon.dart';
 import 'package:stream_chat_flutter/src/utils.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
 
-import '../stream_chat_flutter.dart';
-import 'channel_bottom_sheet.dart';
-import 'channel_preview.dart';
 
 /// Callback called when tapping on a channel
 typedef ChannelTapCallback = void Function(Channel, Widget?);
@@ -17,6 +16,7 @@ typedef ChannelTapCallback = void Function(Channel, Widget?);
 /// Builder used to create a custom [ChannelPreview] from a [Channel]
 typedef ChannelPreviewBuilder = Widget Function(BuildContext, Channel);
 
+/// Callback for when 'View Info' is tapped
 typedef ViewInfoCallback = void Function(Channel);
 
 /// ![screenshot](https://raw.githubusercontent.com/GetStream/stream-chat-flutter/master/screenshots/channel_list_view.png)
@@ -47,10 +47,12 @@ typedef ViewInfoCallback = void Function(Channel);
 /// ```
 ///
 ///
-/// Make sure to have a [StreamChat] ancestor in order to provide the information about the channels.
+/// Make sure to have a [StreamChat] ancestor in order to provide the
+/// information about the channels.
 /// The widget uses a [ListView.custom] to render the list of channels.
 ///
-/// The widget components render the ui based on the first ancestor of type [StreamChatTheme].
+/// The widget components render the ui based on the first ancestor of
+/// type [StreamChatTheme].
 /// Modify it to change the widget appearance.
 class ChannelListView extends StatefulWidget {
   /// Instantiate a new ChannelListView
@@ -94,8 +96,10 @@ class ChannelListView extends StatefulWidget {
   final Map<String, dynamic>? options;
 
   /// The sorting used for the channels matching the filters.
-  /// Sorting is based on field and direction, multiple sorting options can be provided.
+  /// Sorting is based on field and direction, multiple sorting options
-  /// You can sort based on last_updated, last_message_at, updated_at, created_at or member_count.
+  /// can be provided.
+  /// You can sort based on last_updated, last_message_at, updated_at,
+  /// created_at or member_count.
   /// Direction can be ascending or descending.
   final List<SortOption<ChannelModel>>? sort;
 
@@ -137,8 +141,10 @@ class ChannelListView extends StatefulWidget {
   /// The amount of space by which to inset the children.
   final EdgeInsetsGeometry? padding;
 
+  /// List of selected channels which are displayed differently
   final List<Channel> selectedChannels;
 
+  /// Callback for when 'View Info' is tapped
   final ViewInfoCallback? onViewInfoTap;
 
   /// The builder that will be used in case of error
@@ -203,15 +209,14 @@ class _ChannelListViewState extends State<ChannelListView> {
             crossAxisCount: widget.crossAxisCount,
           ),
           itemCount: channels.length,
-          physics: AlwaysScrollableScrollPhysics(),
+          physics: const AlwaysScrollableScrollPhysics(),
-          itemBuilder: (context, index) {
+          itemBuilder: (context, index) =>
-            return _gridItemBuilder(context, index, channels);
+              _gridItemBuilder(context, index, channels),
-          },
         );
       } else {
         child = ListView.separated(
           padding: widget.padding,
-          physics: AlwaysScrollableScrollPhysics(),
+          physics: const AlwaysScrollableScrollPhysics(),
           itemCount:
               channels.isNotEmpty ? channels.length + 1 : channels.length,
           separatorBuilder: (_, index) {
@@ -220,9 +225,8 @@ class _ChannelListViewState extends State<ChannelListView> {
             }
             return _separatorBuilder(context, index);
           },
-          itemBuilder: (context, index) {
+          itemBuilder: (context, index) =>
-            return _listItemBuilder(context, index, channels);
+              _listItemBuilder(context, index, channels),
-          },
         );
       }
     }
@@ -233,11 +237,9 @@ class _ChannelListViewState extends State<ChannelListView> {
     );
   }
 
-  Widget _buildEmptyWidget(BuildContext context) {
+  Widget _buildEmptyWidget(BuildContext context) => LayoutBuilder(
-    return LayoutBuilder(
+        builder: (context, viewportConstraints) => SingleChildScrollView(
-      builder: (context, viewportConstraints) {
+          physics: const AlwaysScrollableScrollPhysics(),
-        return SingleChildScrollView(
-          physics: AlwaysScrollableScrollPhysics(),
           child: Stack(
             children: [
               ConstrainedBox(
@@ -307,15 +309,12 @@ class _ChannelListViewState extends State<ChannelListView> {
                 ),
             ],
           ),
+        ),
       );
-      },
-    );
-  }
 
-  Widget _buildLoadingWidget(BuildContext context) {
+  Widget _buildLoadingWidget(BuildContext context) => ListView(
-    return ListView(
         padding: widget.padding,
-      physics: AlwaysScrollableScrollPhysics(),
+        physics: const AlwaysScrollableScrollPhysics(),
         children: List.generate(
           25,
           (i) {
@@ -331,7 +330,6 @@ class _ChannelListViewState extends State<ChannelListView> {
           },
         ),
       );
-  }
 
   Shimmer _buildLoadingItem(BuildContext context) {
     if (widget.crossAxisCount > 1) {
@@ -340,24 +338,24 @@ class _ChannelListViewState extends State<ChannelListView> {
         highlightColor: StreamChatTheme.of(context).colorTheme.whiteSmoke,
         child: Column(
           children: [
-            SizedBox(height: 4),
+            const SizedBox(height: 4),
             Row(
               mainAxisAlignment: MainAxisAlignment.spaceEvenly,
               children: [
                 for (int i = 0; i < widget.crossAxisCount; i++)
                   Container(
-                    decoration: BoxDecoration(
+                    decoration: const BoxDecoration(
                       color: Colors.white,
                       shape: BoxShape.circle,
                     ),
-                    constraints: BoxConstraints.tightFor(
+                    constraints: const BoxConstraints.tightFor(
                       height: 70,
                       width: 70,
                     ),
                   ),
               ],
             ),
-            SizedBox(
+            const SizedBox(
               height: 16,
             ),
           ],
@@ -373,7 +371,7 @@ class _ChannelListViewState extends State<ChannelListView> {
               color: StreamChatTheme.of(context).colorTheme.white,
               shape: BoxShape.circle,
             ),
-            constraints: BoxConstraints.tightFor(
+            constraints: const BoxConstraints.tightFor(
               height: 40,
               width: 40,
             ),
@@ -389,7 +387,7 @@ class _ChannelListViewState extends State<ChannelListView> {
                 color: StreamChatTheme.of(context).colorTheme.white,
                 borderRadius: BorderRadius.circular(11),
               ),
-              constraints: BoxConstraints.tightFor(
+              constraints: const BoxConstraints.tightFor(
                 height: 16,
                 width: 82,
               ),
@@ -406,7 +404,7 @@ class _ChannelListViewState extends State<ChannelListView> {
                       color: StreamChatTheme.of(context).colorTheme.white,
                       borderRadius: BorderRadius.circular(11),
                     ),
-                    constraints: BoxConstraints.expand(
+                    constraints: const BoxConstraints.expand(
                       height: 16,
                     ),
                   ),
@@ -418,7 +416,7 @@ class _ChannelListViewState extends State<ChannelListView> {
                   color: StreamChatTheme.of(context).colorTheme.white,
                   borderRadius: BorderRadius.circular(11),
                 ),
-                constraints: BoxConstraints.tightFor(
+                constraints: const BoxConstraints.tightFor(
                   height: 16,
                   width: 42,
                 ),
@@ -430,17 +428,16 @@ class _ChannelListViewState extends State<ChannelListView> {
     }
   }
 
-  Widget _buildErrorWidget(BuildContext context, Object error) {
+  Widget _buildErrorWidget(BuildContext context, Object error) => Center(
-    return Center(
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
           children: <Widget>[
             Text.rich(
-            TextSpan(
+              const TextSpan(
                 children: [
                   WidgetSpan(
                     child: Padding(
-                    padding: const EdgeInsets.only(
+                      padding: EdgeInsets.only(
                         right: 2,
                       ),
                       child: Icon(Icons.error_outline),
@@ -453,12 +450,11 @@ class _ChannelListViewState extends State<ChannelListView> {
             ),
             TextButton(
               onPressed: () => _channelListController.loadData!(),
-            child: Text('Retry'),
+              child: const Text('Retry'),
             ),
           ],
         ),
       );
-  }
 
   Widget _listItemBuilder(BuildContext context, int i, List<Channel> channels) {
     final channelsProvider = ChannelsBloc.of(context);
@@ -471,11 +467,10 @@ class _ChannelListViewState extends State<ChannelListView> {
         key: ValueKey<String>('CHANNEL-${channel.id}'),
         channel: channel,
         child: Builder(
-          builder: (context) {
+          builder: (context) => Slidable(
-            return Slidable(
             controller: _slideController,
             enabled: widget.swipeToAction,
-              actionPane: SlidableBehindActionPane(),
+            actionPane: const SlidableBehindActionPane(),
             actionExtentRatio: 0.12,
             secondaryActions: <Widget>[
               IconSlideAction(
@@ -484,23 +479,21 @@ class _ChannelListViewState extends State<ChannelListView> {
                 onTap: () {
                   showModalBottomSheet(
                     clipBehavior: Clip.hardEdge,
-                      shape: RoundedRectangleBorder(
+                    shape: const RoundedRectangleBorder(
                       borderRadius: BorderRadius.only(
                         topLeft: Radius.circular(32),
                         topRight: Radius.circular(32),
                       ),
                     ),
                     context: context,
-                      builder: (context) {
+                    builder: (context) => StreamChannel(
-                        return StreamChannel(
                       channel: channel,
                       child: ChannelBottomSheet(
                         onViewInfoTap: () {
                           widget.onViewInfoTap?.call(channel);
                         },
                       ),
-                        );
+                    ),
-                      },
                   );
                 },
               ),
@@ -525,8 +518,7 @@ class _ChannelListViewState extends State<ChannelListView> {
                           'Are you sure you want to delete this conversation?',
                       cancelText: 'CANCEL',
                       icon: StreamSvgIcon.delete(
-                          color:
+                        color: StreamChatTheme.of(context).colorTheme.accentRed,
-                              StreamChatTheme.of(context).colorTheme.accentRed,
                       ),
                     );
                     if (res == true) {
@@ -545,8 +537,7 @@ class _ChannelListViewState extends State<ChannelListView> {
                     onTap: (channel) => onTap(channel, widget.channelWidget),
                   ),
             ),
-            );
+          ),
-          },
         ),
       );
     } else {
@@ -566,12 +557,10 @@ class _ChannelListViewState extends State<ChannelListView> {
         Navigator.push(
           context,
           MaterialPageRoute(
-            builder: (context) {
+            builder: (context) => StreamChannel(
-              return StreamChannel(
               channel: client,
               child: widget.channelWidget!,
-              );
+            ),
-            },
           ),
         );
       };
@@ -593,18 +582,18 @@ class _ChannelListViewState extends State<ChannelListView> {
             channel: channel,
             borderRadius: BorderRadius.circular(32),
             selected: selected,
-            constraints: BoxConstraints.tightFor(
+            constraints: const BoxConstraints.tightFor(
               width: 64,
               height: 64,
             ),
             onTap: () => _getChannelTap(context),
           ),
-          SizedBox(height: 7),
+          const SizedBox(height: 7),
           Padding(
             padding: const EdgeInsets.symmetric(horizontal: 8),
             child: StreamChannel(
               channel: channel,
-              child: ChannelName(
+              child: const ChannelName(
                 textStyle: TextStyle(
                   fontSize: 12,
                   fontWeight: FontWeight.w600,
@@ -620,8 +609,8 @@ class _ChannelListViewState extends State<ChannelListView> {
   Widget _buildQueryProgressIndicator(
     context,
     ChannelsBlocState channelsProvider,
-  ) {
+  ) =>
-    return StreamBuilder<bool>(
+      StreamBuilder<bool>(
           stream: channelsProvider.queryChannelsLoading,
           initialData: false,
           builder: (context, snapshot) {
@@ -631,8 +620,8 @@ class _ChannelListViewState extends State<ChannelListView> {
                     .colorTheme
                     .accentRed
                     .withOpacity(.2),
-              child: Padding(
+                child: const Padding(
-                padding: const EdgeInsets.symmetric(vertical: 16),
+                  padding: EdgeInsets.symmetric(vertical: 16),
                   child: Center(
                     child: Text('Error loading channels'),
                   ),
@@ -640,15 +629,14 @@ class _ChannelListViewState extends State<ChannelListView> {
               );
             }
             return snapshot.data!
-              ? Center(
+                ? const Center(
                     child: Padding(
-                    padding: const EdgeInsets.all(16),
+                      padding: EdgeInsets.all(16),
-                    child: const CircularProgressIndicator(),
+                      child: CircularProgressIndicator(),
                     ),
                   )
-              : Offstage();
+                : const Offstage();
           });
-  }
 
   Widget _separatorBuilder(context, i) {
     final effect = StreamChatTheme.of(context).colorTheme.borderBottom;

packages/stream_chat_flutter/lib/src/channel_name.dart

@@ -1,12 +1,13 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
 
-import '../stream_chat_flutter.dart';
 
 /// It shows the current [Channel] name using a [Text] widget.
 ///
-/// The widget uses a [StreamBuilder] to render the channel information image as soon as it updates.
+/// The widget uses a [StreamBuilder] to render the channel information
+/// image as soon as it updates.
 class ChannelName extends StatelessWidget {
   /// Instantiate a new ChannelName
   const ChannelName({
@@ -25,9 +26,8 @@ class ChannelName extends StatelessWidget {
     return StreamBuilder<Map<String, dynamic>>(
       stream: channel.extraDataStream,
       initialData: channel.extraData,
-      builder: (context, snapshot) {
+      builder: (context, snapshot) =>
-        return _buildName(snapshot.data!, channel.state?.members, client);
+          _buildName(snapshot.data!, channel.state?.members, client),
-      },
     );
   }
 
@@ -35,8 +35,8 @@ class ChannelName extends StatelessWidget {
     Map<String, dynamic> extraData,
     List<Member>? members,
     StreamChatState client,
-  ) {
+  ) =>
-    return LayoutBuilder(
+      LayoutBuilder(
         builder: (context, constraints) {
           String? title;
           if (extraData['name'] == null) {
@@ -50,7 +50,8 @@ class ChannelName extends StatelessWidget {
               var currentChars = 0;
               final currentMembers = <Member>[];
               otherMembers!.forEach((element) {
-              final newLength = currentChars + (element.user?.name.length ?? 0);
+                final newLength =
+                    currentChars + (element.user?.name.length ?? 0);
                 if (newLength < maxChars) {
                   currentChars = newLength;
                   currentMembers.add(element);
@@ -60,7 +61,8 @@ class ChannelName extends StatelessWidget {
               final exceedingMembers =
                   otherMembers.length - currentMembers.length;
               title =
-                '${currentMembers.map((e) => e.user?.name).join(', ')} ${exceedingMembers > 0 ? '+ $exceedingMembers' : ''}';
+                  '${currentMembers.map((e) => e.user?.name).join(', ')} '
+                      '${exceedingMembers > 0 ? '+ $exceedingMembers' : ''}';
             } else {
               title = 'No title';
             }
@@ -76,4 +78,3 @@ class ChannelName extends StatelessWidget {
         },
       );
 }
-}

packages/stream_chat_flutter/lib/src/channel_preview.dart

@@ -3,23 +3,39 @@ import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 import 'package:jiffy/jiffy.dart';
 import 'package:stream_chat_flutter/src/stream_svg_icon.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
 
-import '../stream_chat_flutter.dart';
-import 'channel_name.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)
 ///
 /// It shows the current [Channel] preview.
 ///
-/// The widget uses a [StreamBuilder] to render the channel information image as soon as it updates.
+/// The widget uses a [StreamBuilder] to render the channel information
+/// image as soon as it updates.
 ///
-/// Usually you don't use this widget as it's the default channel preview used by [ChannelListView].
+/// Usually you don't use this widget as it's the default channel preview
+/// used by [ChannelListView].
 ///
-/// The widget renders the ui based on the first ancestor of type [StreamChatTheme].
+/// The widget renders the ui based on the first ancestor of type
+/// [StreamChatTheme].
 /// Modify it to change the widget appearance.
 class ChannelPreview extends StatelessWidget {
+
+  /// Constructor for creating [ChannelPreview]
+  const ChannelPreview({
+    required this.channel,
+    Key? key,
+    this.onTap,
+    this.onLongPress,
+    this.onImageTap,
+    this.title,
+    this.subtitle,
+    this.leading,
+    this.sendingIndicator,
+    this.trailing,
+  }) : super(key: key);
+
   /// Function called when tapping this widget
   final void Function(Channel)? onTap;
 
@@ -38,36 +54,25 @@ class ChannelPreview extends StatelessWidget {
   /// Widget rendering the subtitle
   final Widget? subtitle;
 
-  /// Widget rendering the leading element, by default it shows the [ChannelImage]
+  /// Widget rendering the leading element, by default
+  /// it shows the [ChannelImage]
   final Widget? leading;
 
-  /// Widget rendering the trailing element, by default it shows the last message date
+  /// Widget rendering the trailing element,
+  /// by default it shows the last message date
   final Widget? trailing;
 
-  /// Widget rendering the sending indicator, by default it uses the [SendingIndicator] widget
+  /// Widget rendering the sending indicator,
+  /// by default it uses the [SendingIndicator] widget
   final Widget? sendingIndicator;
 
-  const ChannelPreview({
-    required this.channel,
-    Key? key,
-    this.onTap,
-    this.onLongPress,
-    this.onImageTap,
-    this.title,
-    this.subtitle,
-    this.leading,
-    this.sendingIndicator,
-    this.trailing,
-  }) : super(key: key);
-
   @override
   Widget build(BuildContext context) {
     final channelPreviewTheme = StreamChatTheme.of(context).channelPreviewTheme;
     return StreamBuilder<bool>(
         stream: channel.isMutedStream,
         initialData: channel.isMuted,
-        builder: (context, snapshot) {
+        builder: (context, snapshot) => Opacity(
-          return Opacity(
               opacity: snapshot.data! ? 0.5 : 1,
               child: ListTile(
                 visualDensity: VisualDensity.compact,
@@ -105,7 +110,7 @@ class ChannelPreview extends StatelessWidget {
                             snapshot.data!.isEmpty ||
                             !snapshot.data!.any((Member e) =>
                                 e.user!.id == channel.client.state.user?.id)) {
-                        return SizedBox();
+                          return const SizedBox();
                         }
                         return UnreadIndicator(
                           cid: channel.cid,
@@ -143,24 +148,22 @@ class ChannelPreview extends StatelessWidget {
                                 ),
                               );
                             }
-                          return SizedBox();
+                            return const SizedBox();
                           },
                         ),
                     trailing ?? _buildDate(context),
                   ],
                 ),
               ),
-          );
+            ));
-        });
   }
 
-  Widget _buildDate(BuildContext context) {
+  Widget _buildDate(BuildContext context) => StreamBuilder<DateTime?>(
-    return StreamBuilder<DateTime?>(
         stream: channel.lastMessageAtStream,
         initialData: channel.lastMessageAt,
         builder: (context, snapshot) {
           if (!snapshot.hasData) {
-          return SizedBox();
+            return const SizedBox();
           }
           final lastMessageAt = snapshot.data!.toLocal();
 
@@ -173,7 +176,9 @@ class ChannelPreview extends StatelessWidget {
               startOfDay.millisecondsSinceEpoch) {
             stringDate = Jiffy(lastMessageAt.toLocal()).jm;
           } else if (lastMessageAt.millisecondsSinceEpoch >=
-            startOfDay.subtract(Duration(days: 1)).millisecondsSinceEpoch) {
+              startOfDay
+                  .subtract(const Duration(days: 1))
+                  .millisecondsSinceEpoch) {
             stringDate = 'Yesterday';
           } else if (startOfDay.difference(lastMessageAt).inDays < 7) {
             stringDate = Jiffy(lastMessageAt.toLocal()).EEEE;
@@ -183,11 +188,11 @@ class ChannelPreview extends StatelessWidget {
 
           return Text(
             stringDate,
-          style: StreamChatTheme.of(context).channelPreviewTheme.lastMessageAt,
+            style:
+                StreamChatTheme.of(context).channelPreviewTheme.lastMessageAt,
           );
         },
       );
-  }
 
   Widget _buildSubtitle(BuildContext context) {
     if (channel.isMuted) {
@@ -211,15 +216,15 @@ class ChannelPreview extends StatelessWidget {
     );
   }
 
-  Widget _buildLastMessage(BuildContext context) {
+  Widget _buildLastMessage(BuildContext context) =>
-    return StreamBuilder<List<Message>?>(
+      StreamBuilder<List<Message>?>(
         stream: channel.state!.messagesStream,
         initialData: channel.state!.messages,
         builder: (context, snapshot) {
           final lastMessage = snapshot.data
               ?.lastWhereOrNull((m) => m.shadowed != true && !m.isDeleted);
           if (lastMessage == null) {
-          return SizedBox();
+            return const SizedBox();
           }
 
           var text = lastMessage.text;
@@ -246,7 +251,10 @@ class ChannelPreview extends StatelessWidget {
               text,
               lastMessage.mentionedUsers,
               lastMessage.attachments,
-            StreamChatTheme.of(context).channelPreviewTheme.subtitle?.copyWith(
+              StreamChatTheme.of(context)
+                  .channelPreviewTheme
+                  .subtitle
+                  ?.copyWith(
                       color: StreamChatTheme.of(context)
                           .channelPreviewTheme
                           .subtitle
@@ -254,7 +262,10 @@ class ChannelPreview extends StatelessWidget {
                       fontStyle: (lastMessage.isSystem || lastMessage.isDeleted)
                           ? FontStyle.italic
                           : FontStyle.normal),
-            StreamChatTheme.of(context).channelPreviewTheme.subtitle?.copyWith(
+              StreamChatTheme.of(context)
+                  .channelPreviewTheme
+                  .subtitle
+                  ?.copyWith(
                     color: StreamChatTheme.of(context)
                         .channelPreviewTheme
                         .subtitle
@@ -270,7 +281,6 @@ class ChannelPreview extends StatelessWidget {
           );
         },
       );
-  }
 
   TextSpan _getDisplayText(
     String text,

packages/stream_chat_flutter/lib/src/connection_status_builder.dart

@@ -1,13 +1,12 @@
 import 'package:flutter/material.dart';
+import 'package:stream_chat_flutter/stream_chat_flutter.dart';
 import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
 
-import 'stream_chat.dart';
-
 /// Widget that builds itself based on the latest snapshot of interaction with
 /// a [Stream] of type [ConnectionStatus].
 ///
-/// The widget will use the closest [StreamChatClient.wsConnectionStatusStream] in case no
+/// The widget will use the closest [StreamChatClient.wsConnectionStatusStream]
-/// stream is provided.
+/// in case no stream is provided.
 class ConnectionStatusBuilder extends StatelessWidget {
   /// Creates a new ConnectionStatusBuilder
   const ConnectionStatusBuilder({
@@ -47,11 +46,11 @@ class ConnectionStatusBuilder extends StatelessWidget {
           if (errorBuilder != null) {
             return errorBuilder!(context, snapshot.error);
           }
-          return Offstage();
+          return const Offstage();
         }
         if (!snapshot.hasData) {
           if (loadingBuilder != null) return loadingBuilder!(context);
-          return Offstage();
+          return const Offstage();
         }
         return statusBuilder(context, snapshot.data!);
       },

packages/stream_chat_flutter/lib/src/date_divider.dart

@@ -4,15 +4,20 @@ import 'package:stream_chat_flutter/src/stream_chat_theme.dart';
 
 /// It shows a date divider depending on the date difference
 class DateDivider extends StatelessWidget {
-  final DateTime dateTime;
-  final bool uppercase;
 
+  /// Constructor for creating a [DateDivider]
   const DateDivider({
     Key? key,
     required this.dateTime,
     this.uppercase = false,
   }) : super(key: key);
 
+  /// [DateTime] to display
+  final DateTime dateTime;
+
+  /// If text is uppercase
+  final bool uppercase;
+
   @override
   Widget build(BuildContext context) {
     final createdAt = Jiffy(dateTime);
@@ -22,10 +27,10 @@ class DateDivider extends StatelessWidget {
     if (Jiffy(createdAt).isSame(now, Units.DAY)) {
       dayInfo = 'Today';
     } else if (Jiffy(createdAt)
-        .isSame(now.subtract(Duration(days: 1)), Units.DAY)) {
+        .isSame(now.subtract(const Duration(days: 1)), Units.DAY)) {
       dayInfo = 'Yesterday';
     } else if (Jiffy(createdAt).isAfter(
-      now.subtract(Duration(days: 7)),
+      now.subtract(const Duration(days: 7)),
       Units.DAY,
     )) {
       dayInfo = createdAt.EEEE;

packages/stream_chat_flutter/lib/src/deleted_message.dart

@@ -3,7 +3,10 @@ import 'dart:math';
 import 'package:flutter/material.dart';
 import 'package:stream_chat_flutter/src/stream_chat_theme.dart';
 
+/// Widget to display deleted message
 class DeletedMessage extends StatelessWidget {
+
+  /// Constructor to create [DeletedMessage]
   const DeletedMessage({
     Key? key,
     required this.messageTheme,
@@ -29,8 +32,7 @@ class DeletedMessage extends StatelessWidget {
   final bool reverse;
 
   @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context) => Transform(
-    return Transform(
       transform: Matrix4.rotationY(reverse ? pi : 0),
       alignment: Alignment.center,
       child: Material(
@@ -71,4 +73,3 @@ class DeletedMessage extends StatelessWidget {
       ),
     );
 }
-}

packages/stream_chat_flutter/lib/src/extension.dart

@@ -9,9 +9,7 @@ final _emojis = Emoji.all();
 /// String extension
 extension StringExtension on String {
   /// Returns the capitalized string
-  String capitalize() {
+  String capitalize() => '${this[0].toUpperCase()}${substring(1)}';
-    return '${this[0].toUpperCase()}${substring(1)}';
-  }
 
   /// Returns whether the string contains only emoji's or not.
   ///
@@ -46,7 +44,9 @@ extension PlatformFileX on PlatformFile {
       );
 }
 
+///
 extension InputDecorationX on InputDecoration {
+  ///
   InputDecoration merge(InputDecoration? other) {
     if (other == null) return this;
     return copyWith(
@@ -98,7 +98,9 @@ extension InputDecorationX on InputDecoration {
   }
 }
 
+/// Gets text scale factor through context
 extension BuildContextX on BuildContext {
+  // ignore: public_member_api_docs
   double get textScaleFactor =>
       MediaQuery.maybeOf(this)?.textScaleFactor ?? 1.0;
 }