flutter · rkishan516 · Apr 12, 2025 · Apr 30, 2025 · Apr 30, 2025 · Apr 30, 2025
diff --git a/packages/flutter/lib/src/cupertino/theme.dart b/packages/flutter/lib/src/cupertino/theme.dart
@@ -66,6 +66,9 @@ class CupertinoTheme extends StatelessWidget {
   ///
   /// Resolves all the colors defined in that [CupertinoThemeData] against the
   /// given [BuildContext] on a best-effort basis.
+  ///
+  /// For specific theme properties, consider using [selectOf],
+  /// which will only rebuild widget when the selected property changes.
   static CupertinoThemeData of(BuildContext context) {
     final InheritedCupertinoTheme? inheritedTheme =
         context.dependOnInheritedWidgetOfExactType<InheritedCupertinoTheme>();
@@ -114,6 +117,19 @@ class CupertinoTheme extends StatelessWidget {
     return inheritedTheme?.theme.data.brightness ?? MediaQuery.maybePlatformBrightnessOf(context);
   }
 
+  /// Evaluates [ThemeSelector.selectFrom] using [data] provided by the
+  /// nearest ancestor [CupertinoTheme] widget, and returns the result.
+  ///
+  /// When this value changes, a notification is sent to the [context]
+  /// to trigger an update.
+  static T selectOf<T>(BuildContext context, T Function(CupertinoThemeData) selector) {
+    final ThemeSelector<CupertinoThemeData, T> themeSelector =
+        ThemeSelector<CupertinoThemeData, T>.from(selector);
+    final InheritedCupertinoTheme? inheritedTheme =
+        InheritedModel.inheritFrom<InheritedCupertinoTheme>(context, aspect: themeSelector);
+    return themeSelector.selectFrom(inheritedTheme?.theme.data ?? const CupertinoThemeData());
+  }
+
   /// The widget below this widget in the tree.
   ///
   /// {@macro flutter.widgets.ProxyWidget.child}
@@ -135,7 +151,7 @@ class CupertinoTheme extends StatelessWidget {
 }
 
 /// Provides a [CupertinoTheme] to all descendents.
-class InheritedCupertinoTheme extends InheritedTheme {
+class InheritedCupertinoTheme extends InheritedTheme<CupertinoThemeData> {
   /// Creates an [InheritedTheme] that provides a [CupertinoTheme] to all
   /// descendents.
   const InheritedCupertinoTheme({super.key, required this.theme, required super.child});
@@ -149,7 +165,7 @@ class InheritedCupertinoTheme extends InheritedTheme {
   }
 
   @override
-  bool updateShouldNotify(InheritedCupertinoTheme oldWidget) => theme.data != oldWidget.theme.data;
+  CupertinoThemeData get themeData => theme.data;
 }
 
 /// Styling specifications for a [CupertinoTheme].

diff --git a/packages/flutter/lib/src/material/action_icons_theme.dart b/packages/flutter/lib/src/material/action_icons_theme.dart
@@ -151,7 +151,7 @@ class ActionIconThemeData with Diagnosticable {
 ///
 /// ** See code in examples/api/lib/material/action_buttons/action_icon_theme.0.dart **
 /// {@end-tool}
-class ActionIconTheme extends InheritedTheme {
+class ActionIconTheme extends InheritedTheme<ActionIconThemeData> {
   /// Creates a theme that overrides the default icon of [BackButtonIcon],
   /// [CloseButtonIcon], [DrawerButtonIcon], and [EndDrawerButtonIcon] in this
   /// widget's subtree.
@@ -166,6 +166,15 @@ class ActionIconTheme extends InheritedTheme {
   /// If there is no enclosing [ActionIconTheme] widget, then
   /// [ThemeData.actionIconTheme] is used.
   ///
+  /// For specific theme properties, consider using [selectOf],
+  /// which will only rebuild widget when the selected property changes:
+  /// ```dart
+  /// final Widget Function(BuildContext)? closeButtonIconBuilder = ActionIconTheme.selectOf(
+  ///   context,
+  ///   (ActionIconThemeData data) => data.closeButtonIconBuilder
+  /// );
+  /// ```
+  ///
   /// Typical usage is as follows:
   ///
   /// ```dart
@@ -177,11 +186,24 @@ class ActionIconTheme extends InheritedTheme {
     return actionIconTheme?.data ?? Theme.of(context).actionIconTheme;
   }
 
+  /// Evaluates [ThemeSelector.selectFrom] using [data] provided by the
+  /// nearest ancestor [ActionIconTheme] widget, and returns the result.
+  ///
+  /// When this value changes, a notification is sent to the [context]
+  /// to trigger an update.
+  static T selectOf<T>(BuildContext context, T Function(ActionIconThemeData) selector) {
+    final ThemeSelector<ActionIconThemeData, T> themeSelector =
+        ThemeSelector<ActionIconThemeData, T>.from(selector);
+    final ActionIconThemeData theme =
+        InheritedModel.inheritFrom<ActionIconTheme>(context, aspect: themeSelector)!.data;
+    return themeSelector.selectFrom(theme);
+  }
+
   @override
   Widget wrap(BuildContext context, Widget child) {
     return ActionIconTheme(data: data, child: child);
   }
 
   @override
-  bool updateShouldNotify(ActionIconTheme oldWidget) => data != oldWidget.data;
+  ActionIconThemeData get themeData => data;
 }
diff --git a/packages/flutter/lib/src/material/badge_theme.dart b/packages/flutter/lib/src/material/badge_theme.dart
@@ -163,7 +163,7 @@ class BadgeThemeData with Diagnosticable {
 ///
 /// Values specified here override the defaults for [Badge] properties which
 /// are not given an explicit non-null value.
-class BadgeTheme extends InheritedTheme {
+class BadgeTheme extends InheritedTheme<BadgeThemeData> {
   /// Creates a theme that overrides the default color parameters for [Badge]s
   /// in this widget's subtree.
   const BadgeTheme({super.key, required this.data, required super.child});
@@ -176,6 +176,15 @@ class BadgeTheme extends InheritedTheme {
   /// If there is no enclosing [BadgeTheme] widget, then
   /// [ThemeData.badgeTheme] is used.
   ///
+  /// For specific theme properties, consider using [selectOf],
+  /// which will only rebuild widget when the selected property changes:
+  /// ```dart
+  /// final Color? backgroundColor = BadgeTheme.selectOf(
+  ///   context,
+  ///   (BadgeThemeData data) => data.backgroundColor,
+  /// );
+  /// ```
+  ///
   /// Typical usage is as follows:
   ///
   /// ```dart
@@ -186,11 +195,25 @@ class BadgeTheme extends InheritedTheme {
     return badgeTheme?.data ?? Theme.of(context).badgeTheme;
   }
 
+  /// Evaluates [ThemeSelector.selectFrom] using [data] provided by the
+  /// nearest ancestor [BadgeTheme] widget, and returns the result.
+  ///
+  /// When this value changes, a notification is sent to the [context]
+  /// to trigger an update.
+  static T selectOf<T>(BuildContext context, T Function(BadgeThemeData) selector) {
+    final ThemeSelector<BadgeThemeData, T> themeSelector = ThemeSelector<BadgeThemeData, T>.from(
+      selector,
+    );
+    final BadgeThemeData theme =
+        InheritedModel.inheritFrom<BadgeTheme>(context, aspect: themeSelector)!.data;
+    return themeSelector.selectFrom(theme);
+  }
+
   @override
   Widget wrap(BuildContext context, Widget child) {
     return BadgeTheme(data: data, child: child);
   }
 
   @override
-  bool updateShouldNotify(BadgeTheme oldWidget) => data != oldWidget.data;
+  BadgeThemeData get themeData => data;
 }
diff --git a/packages/flutter/lib/src/material/banner_theme.dart b/packages/flutter/lib/src/material/banner_theme.dart
@@ -171,7 +171,7 @@ class MaterialBannerThemeData with Diagnosticable {
 ///
 /// Values specified here are used for [MaterialBanner] properties that are not
 /// given an explicit non-null value.
-class MaterialBannerTheme extends InheritedTheme {
+class MaterialBannerTheme extends InheritedTheme<MaterialBannerThemeData> {
   /// Creates a banner theme that controls the configurations for
   /// [MaterialBanner]s in its widget subtree.
   const MaterialBannerTheme({super.key, this.data, required super.child});
@@ -185,6 +185,15 @@ class MaterialBannerTheme extends InheritedTheme {
   /// If there is no ancestor, it returns [ThemeData.bannerTheme]. Applications
   /// can assume that the returned value will not be null.
   ///
+  /// For specific theme properties, consider using [selectOf],
+  /// which will only rebuild widget when the selected property changes:
+  /// ```dart
+  /// final Color? backgroundColor = MaterialBannerTheme.selectOf(
+  ///   context,
+  ///   (MaterialBannerThemeData data) => data.backgroundColor!,
+  /// );
+  /// ```
+  ///
   /// Typical usage is as follows:
   ///
   /// ```dart
@@ -196,11 +205,42 @@ class MaterialBannerTheme extends InheritedTheme {
     return bannerTheme?.data ?? Theme.of(context).bannerTheme;
   }
 
+  /// Evaluates [ThemeSelector.selectFrom] using [data] provided by the
+  /// nearest ancestor [MaterialBannerTheme] widget, and returns the result.
+  ///
+  /// When this value changes, a notification is sent to the [context]
+  /// to trigger an update.
+  static T? selectOf<T>(BuildContext context, T Function(MaterialBannerThemeData) selector) {
+    final ThemeSelector<MaterialBannerThemeData, T> themeSelector =
+        ThemeSelector<MaterialBannerThemeData, T>.from(selector);
+    final MaterialBannerThemeData? theme =
+        InheritedModel.inheritFrom<MaterialBannerTheme>(context, aspect: themeSelector)?.data;
+    return theme == null ? null : themeSelector.selectFrom(theme);
+  }
+
   @override
   Widget wrap(BuildContext context, Widget child) {
     return MaterialBannerTheme(data: data, child: child);
   }
 
   @override
   bool updateShouldNotify(MaterialBannerTheme oldWidget) => data != oldWidget.data;
+
+  @override
+  bool updateShouldNotifyDependent(
+    MaterialBannerTheme oldWidget,
+    Set<ThemeSelector<MaterialBannerThemeData, Object?>> dependencies,
+  ) {
+    for (final ThemeSelector<MaterialBannerThemeData, Object?> selector in dependencies) {
+      final Object? oldValue = oldWidget.data == null ? null : selector.selectFrom(oldWidget.data!);
+      final Object? newValue = data == null ? null : selector.selectFrom(data!);
+      if (oldValue != newValue) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  @override
+  MaterialBannerThemeData get themeData => data!;
 }
diff --git a/packages/flutter/lib/src/material/button_theme.dart b/packages/flutter/lib/src/material/button_theme.dart
@@ -78,7 +78,7 @@ enum ButtonBarLayoutBehavior {
 ///
 ///  * [RawMaterialButton], which can be used to configure a button that doesn't
 ///    depend on any inherited themes.
-class ButtonTheme extends InheritedTheme {
+class ButtonTheme extends InheritedTheme<ButtonThemeData> {
   /// Creates a button theme.
   ButtonTheme({
     super.key,
@@ -126,6 +126,14 @@ class ButtonTheme extends InheritedTheme {
 
   /// The closest instance of this class that encloses the given context.
   ///
+  /// For specific theme properties, consider using [selectOf],
+  /// which will only rebuild widget when the selected property changes:
+  /// ```dart
+  /// final double height = ButtonTheme.selectOf(
+  ///   context, (ButtonThemeData data) => data.height,
+  /// );
+  /// ```
+  ///
   /// Typical usage is as follows:
   ///
   /// ```dart
@@ -149,13 +157,27 @@ class ButtonTheme extends InheritedTheme {
     return buttonTheme!;
   }
 
+  /// Evaluates [ThemeSelector.selectFrom] using [data] provided by the
+  /// nearest ancestor [ButtonTheme] widget, and returns the result.
+  ///
+  /// When this value changes, a notification is sent to the [context]
+  /// to trigger an update.
+  static T selectOf<T>(BuildContext context, T Function(ButtonThemeData) selector) {
+    final ThemeSelector<ButtonThemeData, T> themeSelector = ThemeSelector<ButtonThemeData, T>.from(
+      selector,
+    );
+    final ButtonThemeData theme =
+        InheritedModel.inheritFrom<ButtonTheme>(context, aspect: themeSelector)!.data;
+    return themeSelector.selectFrom(theme);
+  }
+
   @override
   Widget wrap(BuildContext context, Widget child) {
     return ButtonTheme.fromButtonThemeData(data: data, child: child);
   }
 
   @override
-  bool updateShouldNotify(ButtonTheme oldWidget) => data != oldWidget.data;
+  ButtonThemeData get themeData => data;
 }
 
 /// Used with [ButtonTheme] to configure the color and geometry of buttons.

diff --git a/packages/flutter/lib/src/material/carousel_theme.dart b/packages/flutter/lib/src/material/carousel_theme.dart
@@ -155,7 +155,7 @@ class CarouselViewThemeData with Diagnosticable {
 ///  * [CarouselViewThemeData], which describes the actual configuration of a carousel
 ///    theme.
 ///  * [Theme], which controls the overall theme inheritance.
-class CarouselViewTheme extends InheritedTheme {
+class CarouselViewTheme extends InheritedTheme<CarouselViewThemeData> {
   /// Creates a carousel theme that configures all descendant [CarouselView] widgets.
   const CarouselViewTheme({super.key, required this.data, required super.child});
 
@@ -171,13 +171,25 @@ class CarouselViewTheme extends InheritedTheme {
     return inheritedTheme?.data ?? Theme.of(context).carouselViewTheme;
   }
 
+  /// Evaluates [ThemeSelector.selectFrom] using [data] provided by the
+  /// nearest ancestor [CarouselViewTheme] widget, and returns the result.
+  ///
+  /// When this value changes, a notification is sent to the [context]
+  /// to trigger an update.
+  static T selectOf<T>(BuildContext context, T Function(CarouselViewThemeData) selector) {
+    final ThemeSelector<CarouselViewThemeData, T> themeSelector =
+        ThemeSelector<CarouselViewThemeData, T>.from(selector);
+    final CarouselViewThemeData theme =
+        InheritedModel.inheritFrom<CarouselViewTheme>(context, aspect: themeSelector)!.data;
+    return themeSelector.selectFrom(theme);
+  }
+
   /// Wraps the given [child] with a [CarouselViewTheme] containing the [data].
   @override
   Widget wrap(BuildContext context, Widget child) {
     return CarouselViewTheme(data: data, child: child);
   }
 
-  /// Returns true if the [data] fields of the two themes are different.
   @override
-  bool updateShouldNotify(CarouselViewTheme oldWidget) => data != oldWidget.data;
+  CarouselViewThemeData get themeData => data;
 }
diff --git a/packages/flutter/lib/src/material/chip_theme.dart b/packages/flutter/lib/src/material/chip_theme.dart
@@ -49,7 +49,7 @@ import 'theme.dart';
 ///    theme.
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
-class ChipTheme extends InheritedTheme {
+class ChipTheme extends InheritedTheme<ChipThemeData> {
   /// Applies the given theme [data] to [child].
   const ChipTheme({super.key, required this.data, required super.child});
 
@@ -63,6 +63,9 @@ class ChipTheme extends InheritedTheme {
   /// Defaults to the ambient [ThemeData.chipTheme] if there is no
   /// [ChipTheme] in the given build context.
   ///
+  /// For specific theme properties, consider using [selectOf],
+  /// which will only rebuild widget when the selected property changes.
+  ///
   /// {@tool snippet}
   ///
   /// ```dart
@@ -92,13 +95,27 @@ class ChipTheme extends InheritedTheme {
     return inheritedTheme?.data ?? Theme.of(context).chipTheme;
   }
 
+  /// Evaluates [ThemeSelector.selectFrom] using [data] provided by the
+  /// nearest ancestor [ChipTheme] widget, and returns the result.
+  ///
+  /// When this value changes, a notification is sent to the [context]
+  /// to trigger an update.
+  static T selectOf<T>(BuildContext context, T Function(ChipThemeData) selector) {
+    final ThemeSelector<ChipThemeData, T> themeSelector = ThemeSelector<ChipThemeData, T>.from(
+      selector,
+    );
+    final ChipThemeData theme =
+        InheritedModel.inheritFrom<ChipTheme>(context, aspect: themeSelector)!.data;
+    return themeSelector.selectFrom(theme);
+  }
+
   @override
   Widget wrap(BuildContext context, Widget child) {
     return ChipTheme(data: data, child: child);
   }
 
   @override
-  bool updateShouldNotify(ChipTheme oldWidget) => data != oldWidget.data;
+  ChipThemeData get themeData => data;
 }
 
 /// Holds the color, shape, and text styles for a Material Design chip theme.