message_list: added pressedTint feature

It allows to see a tint color on the message
when it is pressed.

Moved `MessageWithPossibleSender` to `StatefulWidget`
and used `ModalStatus` return type of
`showMessageActionSheet` to check whether BottomSheet
is open or not.

Added `pressedTint` to `DesignVariables` for using
it in `MessageWithPossibleSender`.

Added tests too in `message_list_test.dart`.

Fixes: #1142

Author: Gaurav-Kushwaha-1225

lib/widgets/action_sheet.dart

@@ -29,11 +29,11 @@ import 'store.dart';
 import 'text.dart';
 import 'theme.dart';
 
-void _showActionSheet(
+ModalStatus _showActionSheet(
   BuildContext context, {
   required List<Widget> optionButtons,
 }) {
-  showModalBottomSheet<void>(
+  final future = showModalBottomSheet<void>(
     context: context,
     // Clip.hardEdge looks bad; Clip.antiAliasWithSaveLayer looks pixel-perfect
     // on my iPhone 13 Pro but is marked as "much slower":
@@ -63,6 +63,7 @@ void _showActionSheet(
               const ActionSheetCancelButton(),
             ])));
     });
+  return ModalStatus(future);
 }
 
 /// A button in an action sheet.
@@ -464,7 +465,7 @@ class ResolveUnresolveButton extends ActionSheetMenuItemButton {
 /// Show a sheet of actions you can take on a message in the message list.
 ///
 /// Must have a [MessageListPage] ancestor.
-void showMessageActionSheet({required BuildContext context, required Message message}) {
+ModalStatus showMessageActionSheet({required BuildContext context, required Message message}) {
   final pageContext = PageRoot.contextOf(context);
   final store = PerAccountStoreWidget.of(pageContext);
 
@@ -492,7 +493,7 @@ void showMessageActionSheet({required BuildContext context, required Message mes
     ShareButton(message: message, pageContext: pageContext),
   ];
 
-  _showActionSheet(pageContext, optionButtons: optionButtons);
+  return _showActionSheet(pageContext, optionButtons: optionButtons);
 }
 
 abstract class MessageActionSheetMenuItemButton extends ActionSheetMenuItemButton {

lib/widgets/content.dart

@@ -1319,7 +1319,6 @@ class MessageTableCell extends StatelessWidget {
 
 void _launchUrl(BuildContext context, String urlString) async {
   ModalStatus showError(BuildContext context, String? message) {
-    final zulipLocalizations = ZulipLocalizations.of(context);
     return showErrorDialog(context: context,
       title: 'Unable to open link',
       message: [

lib/widgets/message_list.dart

@@ -16,6 +16,7 @@ import 'actions.dart';
 import 'app_bar.dart';
 import 'compose_box.dart';
 import 'content.dart';
+import 'dialog.dart';
 import 'emoji_reaction.dart';
 import 'icons.dart';
 import 'page.dart';
@@ -1316,22 +1317,45 @@ String formatHeaderDate(
 // Design referenced from:
 //   - https://github.com/zulip/zulip-mobile/issues/5511
 //   - https://www.figma.com/file/1JTNtYo9memgW7vV6d0ygq/Zulip-Mobile?node-id=538%3A20849&mode=dev
-class MessageWithPossibleSender extends StatelessWidget {
+class MessageWithPossibleSender extends StatefulWidget {
   const MessageWithPossibleSender({super.key, required this.item});
 
   final MessageListMessageItem item;
 
+  @override
+  State<MessageWithPossibleSender> createState() => _MessageWithPossibleSenderState();
+}
+
+class _MessageWithPossibleSenderState extends State<MessageWithPossibleSender> {
+  final WidgetStatesController statesController = WidgetStatesController();
+
+  @override
+  void initState() {
+    super.initState();
+    statesController.addListener(() {
+      setState(() {
+        // Force a rebuild to resolve background color
+      });
+    });
+  }
+
+  @override
+  void dispose() {
+    statesController.dispose();
+    super.dispose();
+  }
+
   @override
   Widget build(BuildContext context) {
     final store = PerAccountStoreWidget.of(context);
     final messageListTheme = MessageListTheme.of(context);
     final designVariables = DesignVariables.of(context);
 
-    final message = item.message;
+    final message = widget.item.message;
     final sender = store.users[message.senderId];
 
     Widget? senderRow;
-    if (item.showSender) {
+    if (widget.item.showSender) {
       final time = _kMessageTimestampFormat
         .format(DateTime.fromMillisecondsSinceEpoch(1000 * message.timestamp));
       senderRow = Row(
@@ -1389,40 +1413,57 @@ class MessageWithPossibleSender extends StatelessWidget {
 
     return GestureDetector(
       behavior: HitTestBehavior.translucent,
-      onLongPress: () => showMessageActionSheet(context: context, message: message),
-      child: Padding(
-        padding: const EdgeInsets.symmetric(vertical: 4),
-        child: Column(children: [
-          if (senderRow != null)
-            Padding(padding: const EdgeInsets.fromLTRB(16, 2, 16, 0),
-              child: senderRow),
-          Row(
-            crossAxisAlignment: CrossAxisAlignment.baseline,
-            textBaseline: localizedTextBaseline(context),
-            children: [
-              const SizedBox(width: 16),
-              Expanded(child: Column(
-                crossAxisAlignment: CrossAxisAlignment.stretch,
-                children: [
-                  MessageContent(message: message, content: item.content),
-                  if ((message.reactions?.total ?? 0) > 0)
-                    ReactionChipsList(messageId: message.id, reactions: message.reactions!),
-                  if (editStateText != null)
-                    Text(editStateText,
-                      textAlign: TextAlign.end,
-                      style: TextStyle(
-                        color: designVariables.labelEdited,
-                        fontSize: 12,
-                        height: (12 / 12),
-                        letterSpacing: proportionalLetterSpacing(
-                          context, 0.05, baseFontSize: 12))),
-                ])),
-              SizedBox(width: 16,
-                child: message.flags.contains(MessageFlag.starred)
-                  ? Icon(ZulipIcons.star_filled, size: 16, color: designVariables.star)
-                  : null),
-            ]),
-        ])));
+      onLongPress: () async {
+        statesController.update(WidgetState.selected, true);
+        ModalStatus status = showMessageActionSheet(context: context,
+          message: message);
+        await status.closed;
+        statesController.update(WidgetState.selected, false);
+      },
+      onLongPressDown: (_) => statesController.update(WidgetState.pressed, true),
+      onLongPressCancel: () => statesController.update(WidgetState.pressed, false),
+      onLongPressUp: () => statesController.update(WidgetState.pressed, false),
+      child: DecoratedBox(
+        decoration: BoxDecoration(
+          color: WidgetStateColor.fromMap({
+            WidgetState.pressed: designVariables.pressedTint,
+            WidgetState.selected: designVariables.pressedTint,
+            WidgetState.any: Colors.transparent,
+          }).resolve(statesController.value)
+        ),
+        child: Padding(
+          padding: const EdgeInsets.symmetric(vertical: 4),
+          child: Column(children: [
+            if (senderRow != null)
+              Padding(padding: const EdgeInsets.fromLTRB(16, 2, 16, 0),
+                child: senderRow),
+            Row(
+              crossAxisAlignment: CrossAxisAlignment.baseline,
+              textBaseline: localizedTextBaseline(context),
+              children: [
+                const SizedBox(width: 16),
+                Expanded(child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.stretch,
+                  children: [
+                    MessageContent(message: message, content: widget.item.content),
+                    if ((message.reactions?.total ?? 0) > 0)
+                      ReactionChipsList(messageId: message.id, reactions: message.reactions!),
+                    if (editStateText != null)
+                      Text(editStateText,
+                        textAlign: TextAlign.end,
+                        style: TextStyle(
+                          color: designVariables.labelEdited,
+                          fontSize: 12,
+                          height: (12 / 12),
+                          letterSpacing: proportionalLetterSpacing(
+                            context, 0.05, baseFontSize: 12))),
+                  ])),
+                SizedBox(width: 16,
+                  child: message.flags.contains(MessageFlag.starred)
+                    ? Icon(ZulipIcons.star_filled, size: 16, color: designVariables.star)
+                    : null),
+              ]),
+          ]))));
   }
 }
 

lib/widgets/theme.dart

@@ -145,6 +145,7 @@ class DesignVariables extends ThemeExtension<DesignVariables> {
     labelEdited: const HSLColor.fromAHSL(0.35, 0, 0, 0).toColor(),
     labelMenuButton: const Color(0xff222222),
     mainBackground: const Color(0xfff0f0f0),
+    pressedTint: const HSLColor.fromAHSL(0.04, 0, 0, 0).toColor(),
     textInput: const Color(0xff000000),
     title: const Color(0xff1a1a1a),
     bgSearchInput: const Color(0xffe3e3e3),
@@ -194,6 +195,7 @@ class DesignVariables extends ThemeExtension<DesignVariables> {
     labelEdited: const HSLColor.fromAHSL(0.35, 0, 0, 1).toColor(),
     labelMenuButton: const Color(0xffffffff).withValues(alpha: 0.85),
     mainBackground: const Color(0xff1d1d1d),
+    pressedTint: const HSLColor.fromAHSL(0.04, 0, 0, 1).toColor(),
     textInput: const Color(0xffffffff).withValues(alpha: 0.9),
     title: const Color(0xffffffff),
     bgSearchInput: const Color(0xff313131),
@@ -251,6 +253,7 @@ class DesignVariables extends ThemeExtension<DesignVariables> {
     required this.labelEdited,
     required this.labelMenuButton,
     required this.mainBackground,
+    required this.pressedTint,
     required this.textInput,
     required this.title,
     required this.bgSearchInput,
@@ -309,6 +312,7 @@ class DesignVariables extends ThemeExtension<DesignVariables> {
   final Color labelEdited;
   final Color labelMenuButton;
   final Color mainBackground;
+  final Color pressedTint;
   final Color textInput;
   final Color title;
   final Color bgSearchInput;
@@ -362,6 +366,7 @@ class DesignVariables extends ThemeExtension<DesignVariables> {
     Color? labelEdited,
     Color? labelMenuButton,
     Color? mainBackground,
+    Color? pressedTint,
     Color? textInput,
     Color? title,
     Color? bgSearchInput,
@@ -410,6 +415,7 @@ class DesignVariables extends ThemeExtension<DesignVariables> {
       labelEdited: labelEdited ?? this.labelEdited,
       labelMenuButton: labelMenuButton ?? this.labelMenuButton,
       mainBackground: mainBackground ?? this.mainBackground,
+      pressedTint: pressedTint ?? this.pressedTint,
       textInput: textInput ?? this.textInput,
       title: title ?? this.title,
       bgSearchInput: bgSearchInput ?? this.bgSearchInput,
@@ -465,6 +471,7 @@ class DesignVariables extends ThemeExtension<DesignVariables> {
       labelEdited: Color.lerp(labelEdited, other.labelEdited, t)!,
       labelMenuButton: Color.lerp(labelMenuButton, other.labelMenuButton, t)!,
       mainBackground: Color.lerp(mainBackground, other.mainBackground, t)!,
+      pressedTint: Color.lerp(pressedTint, other.pressedTint, t)!,
       textInput: Color.lerp(textInput, other.textInput, t)!,
       title: Color.lerp(title, other.title, t)!,
       bgSearchInput: Color.lerp(bgSearchInput, other.bgSearchInput, t)!,

test/widgets/message_list_test.dart

@@ -24,6 +24,7 @@ import 'package:zulip/widgets/message_list.dart';
 import 'package:zulip/widgets/page.dart';
 import 'package:zulip/widgets/store.dart';
 import 'package:zulip/widgets/channel_colors.dart';
+import 'package:zulip/widgets/theme.dart';
 
 import '../api/fake_api.dart';
 import '../example_data.dart' as eg;
@@ -1188,6 +1189,77 @@ void main() {
 
       debugNetworkImageHttpClientProvider = null;
     });
+
+
+    group('action sheet visual feedback', () {
+      late Message message;
+
+      setUp(() {
+        message = eg.streamMessage();
+      });
+
+      Color? getBackgroundColor(WidgetTester tester) {
+        final decoratedBox = tester.widget<DecoratedBox>(
+          find.descendant(
+            of: find.byType(MessageWithPossibleSender),
+            matching: find.byType(DecoratedBox),
+          ),
+        );
+        return (decoratedBox.decoration as BoxDecoration).color;
+      }
+
+      testWidgets('starts with transparent background', (tester) async {
+        await setupMessageListPage(tester, messages: [message]);
+
+        check(getBackgroundColor(tester),
+          because: 'Message should start with transparent background',
+        ).equals(Colors.transparent);
+      });
+
+      testWidgets('shows tint color when long pressed', (tester) async {
+        await setupMessageListPage(tester, messages: [message]);
+
+        await tester.longPress(find.byType(MessageWithPossibleSender));
+        await tester.pump();
+
+        final expectedTint = DesignVariables.of(tester.element(find.byType(MessageWithPossibleSender)))
+          .pressedTint;
+
+        check(getBackgroundColor(tester),
+          because: 'Message should show tint color during long press',
+        ).equals(expectedTint);
+      });
+
+      testWidgets('returns to transparent after action sheet dismissal', (tester) async {
+        await setupMessageListPage(tester, messages: [message]);
+
+        await tester.longPress(find.byType(MessageWithPossibleSender));
+        await tester.pump();
+
+        await tester.tapAt(const Offset(0, 0));
+        await tester.pumpAndSettle();
+
+        check(getBackgroundColor(tester),
+          because: 'Message should return to transparent after dismissal',
+        ).equals(Colors.transparent);
+      });
+
+      testWidgets('maintains tint color while action sheet is open', (tester) async {
+        await setupMessageListPage(tester, messages: [message]);
+
+        await tester.longPress(find.byType(MessageWithPossibleSender));
+        await tester.pump();
+
+        final expectedTint = DesignVariables.of(tester.element(find.byType(MessageWithPossibleSender)))
+          .pressedTint;
+
+        await tester.pump(const Duration(milliseconds: 500));
+
+        check(getBackgroundColor(tester),
+          because: 'Message should continue to show tint color while action sheet is visible',
+        ).equals(expectedTint);
+      });
+    });
   });
 
   group('Starred messages', () {