Update Popup Menu to support Material 3 (#103606)

Author: TahaTesser

dev/tools/gen_defaults/bin/gen_defaults.dart

@@ -33,6 +33,7 @@ import 'package:gen_defaults/input_chip_template.dart';
 import 'package:gen_defaults/input_decorator_template.dart';
 import 'package:gen_defaults/navigation_bar_template.dart';
 import 'package:gen_defaults/navigation_rail_template.dart';
+import 'package:gen_defaults/popup_menu_template.dart';
 import 'package:gen_defaults/progress_indicator_template.dart';
 import 'package:gen_defaults/radio_template.dart';
 import 'package:gen_defaults/surface_tint.dart';
@@ -136,6 +137,7 @@ Future<void> main(List<String> args) async {
   InputDecoratorTemplate('InputDecorator', '$materialLib/input_decorator.dart', tokens).updateFile();
   NavigationBarTemplate('NavigationBar', '$materialLib/navigation_bar.dart', tokens).updateFile();
   NavigationRailTemplate('NavigationRail', '$materialLib/navigation_rail.dart', tokens).updateFile();
+  PopupMenuTemplate('PopupMenu', '$materialLib/popup_menu.dart', tokens).updateFile();
   ProgressIndicatorTemplate('ProgressIndicator', '$materialLib/progress_indicator.dart', tokens).updateFile();
   RadioTemplate('Radio<T>', '$materialLib/radio.dart', tokens).updateFile();
   SurfaceTintTemplate('SurfaceTint', '$materialLib/elevation_overlay.dart', tokens).updateFile();

dev/tools/gen_defaults/lib/popup_menu_template.dart

@@ -0,0 +1,46 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'template.dart';
+
+class PopupMenuTemplate extends TokenTemplate {
+  const PopupMenuTemplate(super.blockName, super.fileName, super.tokens, {
+    super.colorSchemePrefix = '_colors.',
+    super.textThemePrefix = '_textTheme.',
+  });
+
+  @override
+  String generate() => '''
+class _${blockName}DefaultsM3 extends PopupMenuThemeData {
+  _${blockName}DefaultsM3(this.context)
+    : super(elevation: ${elevation('md.comp.menu.container')});
+
+  final BuildContext context;
+  late final ThemeData _theme = Theme.of(context);
+  late final ColorScheme _colors = _theme.colorScheme;
+  late final TextTheme _textTheme = _theme.textTheme;
+
+  @override MaterialStateProperty<TextStyle?>? get labelTextStyle {
+    return MaterialStateProperty.resolveWith((Set<MaterialState> states) {
+    final TextStyle style = _textTheme.labelLarge!;
+      if (states.contains(MaterialState.disabled)) {
+        return style.apply(color: ${componentColor('md.comp.menu.list-item.disabled.label-text')});
+      }
+      return style.apply(color: ${componentColor('md.comp.menu.list-item.label-text')});
+    });
+  }
+
+  @override
+  Color? get color => ${componentColor('md.comp.menu.container')};
+
+  @override
+  Color? get shadowColor => ${color("md.comp.menu.container.shadow-color")};
+
+  @override
+  Color? get surfaceTintColor => ${color("md.comp.menu.container.surface-tint-layer.color")};
+
+  @override
+  ShapeBorder? get shape => ${shape("md.comp.menu.container")};
+}''';
+}

packages/flutter/lib/src/material/popup_menu.dart

@@ -6,6 +6,7 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 
+import 'color_scheme.dart';
 import 'constants.dart';
 import 'debug.dart';
 import 'divider.dart';
@@ -17,6 +18,7 @@ import 'material.dart';
 import 'material_localizations.dart';
 import 'material_state.dart';
 import 'popup_menu_theme.dart';
+import 'text_theme.dart';
 import 'theme.dart';
 import 'tooltip.dart';
 
@@ -224,6 +226,7 @@ class PopupMenuItem<T> extends PopupMenuEntry<T> {
     this.height = kMinInteractiveDimension,
     this.padding,
     this.textStyle,
+    this.labelTextStyle,
     this.mouseCursor,
     required this.child,
   }) : assert(enabled != null),
@@ -263,6 +266,16 @@ class PopupMenuItem<T> extends PopupMenuEntry<T> {
   /// of [ThemeData.textTheme] is used.
   final TextStyle? textStyle;
 
+  /// The label style of the popup menu item.
+  ///
+  /// When [ThemeData.useMaterial3] is true, this styles the text of the popup menu item.
+  ///
+  /// If this property is null, then [PopupMenuThemeData.labelTextStyle] is used.
+  /// If [PopupMenuThemeData.labelTextStyle] is also null, then [TextTheme.labelLarge]
+  /// is used with the [ColorScheme.onSurface] color when popup menu item is enabled and
+  /// the [ColorScheme.onSurface] color with 0.38 opacity when the popup menu item is disabled.
+  final MaterialStateProperty<TextStyle?>? labelTextStyle;
+
   /// {@template flutter.material.popupmenu.mouseCursor}
   /// The cursor for a mouse pointer when it enters or is hovering over the
   /// widget.
@@ -336,9 +349,20 @@ class PopupMenuItemState<T, W extends PopupMenuItem<T>> extends State<W> {
   Widget build(BuildContext context) {
     final ThemeData theme = Theme.of(context);
     final PopupMenuThemeData popupMenuTheme = PopupMenuTheme.of(context);
-    TextStyle style = widget.textStyle ?? popupMenuTheme.textStyle ?? theme.textTheme.titleMedium!;
-
-    if (!widget.enabled) {
+    final PopupMenuThemeData defaults = theme.useMaterial3 ? _PopupMenuDefaultsM3(context) : _PopupMenuDefaultsM2(context);
+    final Set<MaterialState> states = <MaterialState>{
+      if (!widget.enabled) MaterialState.disabled,
+    };
+
+    TextStyle style = theme.useMaterial3
+      ? (widget.labelTextStyle?.resolve(states)
+        ?? popupMenuTheme.labelTextStyle?.resolve(states)!
+        ?? defaults.labelTextStyle!.resolve(states)!)
+      : (widget.textStyle
+        ?? popupMenuTheme.textStyle
+        ?? defaults.textStyle!);
+
+    if (!widget.enabled && !theme.useMaterial3) {
       style = style.copyWith(color: theme.disabledColor);
     }
 
@@ -537,7 +561,9 @@ class _PopupMenu<T> extends StatelessWidget {
   Widget build(BuildContext context) {
     final double unit = 1.0 / (route.items.length + 1.5); // 1.0 for the width and 0.5 for the last item's fade.
     final List<Widget> children = <Widget>[];
+    final ThemeData theme = Theme.of(context);
     final PopupMenuThemeData popupMenuTheme = PopupMenuTheme.of(context);
+    final PopupMenuThemeData defaults = theme.useMaterial3 ? _PopupMenuDefaultsM3(context) : _PopupMenuDefaultsM2(context);
 
     for (int i = 0; i < route.items.length; i += 1) {
       final double start = (i + 1) * unit;
@@ -598,11 +624,13 @@ class _PopupMenu<T> extends StatelessWidget {
         return FadeTransition(
           opacity: opacity.animate(route.animation!),
           child: Material(
-            shape: route.shape ?? popupMenuTheme.shape,
-            color: route.color ?? popupMenuTheme.color,
+            shape: route.shape ?? popupMenuTheme.shape ?? defaults.shape,
+            color: route.color ?? popupMenuTheme.color ?? defaults.color,
             clipBehavior: clipBehavior,
             type: MaterialType.card,
-            elevation: route.elevation ?? popupMenuTheme.elevation ?? 8.0,
+            elevation: route.elevation ?? popupMenuTheme.elevation ?? defaults.elevation!,
+            shadowColor: route.shadowColor ?? popupMenuTheme.shadowColor ?? defaults.shadowColor,
+            surfaceTintColor: route.surfaceTintColor ?? popupMenuTheme.surfaceTintColor ?? defaults.surfaceTintColor,
             child: Align(
               alignment: AlignmentDirectional.topEnd,
               widthFactor: width.evaluate(route.animation!),
@@ -757,6 +785,8 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
     required this.items,
     this.initialValue,
     this.elevation,
+    this.surfaceTintColor,
+    this.shadowColor,
     required this.barrierLabel,
     this.semanticLabel,
     this.shape,
@@ -771,6 +801,8 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
   final List<Size?> itemSizes;
   final T? initialValue;
   final double? elevation;
+  final Color? surfaceTintColor;
+  final Color? shadowColor;
   final String? semanticLabel;
   final ShapeBorder? shape;
   final Color? color;
@@ -911,6 +943,8 @@ Future<T?> showMenu<T>({
   required List<PopupMenuEntry<T>> items,
   T? initialValue,
   double? elevation,
+  Color? shadowColor,
+  Color? surfaceTintColor,
   String? semanticLabel,
   ShapeBorder? shape,
   Color? color,
@@ -941,6 +975,8 @@ Future<T?> showMenu<T>({
     items: items,
     initialValue: initialValue,
     elevation: elevation,
+    shadowColor: shadowColor,
+    surfaceTintColor: surfaceTintColor,
     semanticLabel: semanticLabel,
     barrierLabel: MaterialLocalizations.of(context).modalBarrierDismissLabel,
     shape: shape,
@@ -1006,6 +1042,8 @@ class PopupMenuButton<T> extends StatefulWidget {
     this.onCanceled,
     this.tooltip,
     this.elevation,
+    this.shadowColor,
+    this.surfaceTintColor,
     this.padding = const EdgeInsets.all(8.0),
     this.child,
     this.splashRadius,
@@ -1058,6 +1096,22 @@ class PopupMenuButton<T> extends StatefulWidget {
   /// Defaults to 8, the appropriate elevation for popup menus.
   final double? elevation;
 
+  /// The color used to paint the shadow below the menu.
+  ///
+  /// If null then the ambient [PopupMenuThemeData.shadowColor] is used.
+  /// If that is null too, then the overall theme's [ThemeData.shadowColor]
+  /// (default black) is used.
+  final Color? shadowColor;
+
+  /// The color used as an overlay on [color] to indicate elevation.
+  ///
+  /// If null, [PopupMenuThemeData.surfaceTintColor] is used. If that
+  /// is also null, the default value is [ColorScheme.surfaceTint].
+  ///
+  /// See [Material.surfaceTintColor] for more details on how this
+  /// overlay is applied.
+  final Color? surfaceTintColor;
+
   /// Matches IconButton's 8 dps padding by default. In some cases, notably where
   /// this button appears as the trailing element of a list item, it's useful to be able
   /// to set the padding to zero.
@@ -1207,6 +1261,8 @@ class PopupMenuButtonState<T> extends State<PopupMenuButton<T>> {
       showMenu<T?>(
         context: context,
         elevation: widget.elevation ?? popupMenuTheme.elevation,
+        shadowColor: widget.shadowColor ?? popupMenuTheme.shadowColor,
+        surfaceTintColor: widget.surfaceTintColor ?? popupMenuTheme.surfaceTintColor,
         items: items,
         initialValue: widget.initialValue,
         position: position,
@@ -1240,6 +1296,7 @@ class PopupMenuButtonState<T> extends State<PopupMenuButton<T>> {
 
   @override
   Widget build(BuildContext context) {
+    final IconThemeData iconTheme = IconTheme.of(context);
     final bool enableFeedback = widget.enableFeedback
       ?? PopupMenuTheme.of(context).enableFeedback
       ?? true;
@@ -1263,7 +1320,8 @@ class PopupMenuButtonState<T> extends State<PopupMenuButton<T>> {
       icon: widget.icon ?? Icon(Icons.adaptive.more),
       padding: widget.padding,
       splashRadius: widget.splashRadius,
-      iconSize: widget.iconSize,
+      iconSize: widget.iconSize ?? iconTheme.size,
+      color: widget.color ?? iconTheme.color,
       tooltip: widget.tooltip ?? MaterialLocalizations.of(context).showMenuTooltip,
       onPressed: widget.enabled ? showButtonMenu : null,
       enableFeedback: enableFeedback,
@@ -1290,3 +1348,57 @@ class _EffectiveMouseCursor extends MaterialStateMouseCursor {
   @override
   String get debugDescription => 'MaterialStateMouseCursor(PopupMenuItemState)';
 }
+
+class _PopupMenuDefaultsM2 extends PopupMenuThemeData {
+  _PopupMenuDefaultsM2(this.context)
+    : super(elevation: 8.0);
+
+  final BuildContext context;
+  late final ThemeData _theme = Theme.of(context);
+  late final TextTheme _textTheme = _theme.textTheme;
+
+  @override
+  TextStyle? get textStyle => _textTheme.subtitle1;
+}
+
+// BEGIN GENERATED TOKEN PROPERTIES - PopupMenu
+
+// Do not edit by hand. The code between the "BEGIN GENERATED" and
+// "END GENERATED" comments are generated from data in the Material
+// Design token database by the script:
+//   dev/tools/gen_defaults/bin/gen_defaults.dart.
+
+// Token database version: v0_132
+
+class _PopupMenuDefaultsM3 extends PopupMenuThemeData {
+  _PopupMenuDefaultsM3(this.context)
+    : super(elevation: 3.0);
+
+  final BuildContext context;
+  late final ThemeData _theme = Theme.of(context);
+  late final ColorScheme _colors = _theme.colorScheme;
+  late final TextTheme _textTheme = _theme.textTheme;
+
+  @override MaterialStateProperty<TextStyle?>? get labelTextStyle {
+    return MaterialStateProperty.resolveWith((Set<MaterialState> states) {
+    final TextStyle style = _textTheme.labelLarge!;
+      if (states.contains(MaterialState.disabled)) {
+        return style.apply(color: _colors.onSurface.withOpacity(0.38));
+      }
+      return style.apply(color: _colors.onSurface);
+    });
+  }
+
+  @override
+  Color? get color => _colors.surface;
+
+  @override
+  Color? get shadowColor => _colors.shadow;
+
+  @override
+  Color? get surfaceTintColor => _colors.surfaceTint;
+
+  @override
+  ShapeBorder? get shape => const RoundedRectangleBorder(borderRadius: BorderRadius.all(Radius.circular(4.0)));
+}
+// END GENERATED TOKEN PROPERTIES - PopupMenu