InheritedTheme updates (#69050)

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

@@ -147,8 +147,7 @@ class MaterialBannerTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final MaterialBannerTheme? ancestorTheme = context.findAncestorWidgetOfExactType<MaterialBannerTheme>();
-    return identical(this, ancestorTheme) ? child : MaterialBannerTheme(data: data, child: child);
+    return MaterialBannerTheme(data: data, child: child);
   }
 
   @override

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

@@ -417,7 +417,7 @@ class _ModalBottomSheetState<T> extends State<_ModalBottomSheet<T>> {
 class _ModalBottomSheetRoute<T> extends PopupRoute<T> {
   _ModalBottomSheetRoute({
     this.builder,
-    this.theme,
+    required this.capturedThemes,
     this.barrierLabel,
     this.backgroundColor,
     this.elevation,
@@ -434,7 +434,7 @@ class _ModalBottomSheetRoute<T> extends PopupRoute<T> {
        super(settings: settings);
 
   final WidgetBuilder? builder;
-  final ThemeData? theme;
+  final CapturedThemes capturedThemes;
   final bool isScrollControlled;
   final Color? backgroundColor;
   final double? elevation;
@@ -470,13 +470,15 @@ class _ModalBottomSheetRoute<T> extends PopupRoute<T> {
 
   @override
   Widget buildPage(BuildContext context, Animation<double> animation, Animation<double> secondaryAnimation) {
-    final BottomSheetThemeData sheetTheme = theme?.bottomSheetTheme ?? Theme.of(context)!.bottomSheetTheme;
     // By definition, the bottom sheet is aligned to the bottom of the page
     // and isn't exposed to the top padding of the MediaQuery.
-    Widget bottomSheet = MediaQuery.removePadding(
+    final Widget bottomSheet = MediaQuery.removePadding(
       context: context,
       removeTop: true,
-      child: _ModalBottomSheet<T>(
+      child: Builder(
+        builder: (BuildContext context) {
+          final BottomSheetThemeData sheetTheme = Theme.of(context)!.bottomSheetTheme;
+          return _ModalBottomSheet<T>(
             route: this,
             backgroundColor: backgroundColor ?? sheetTheme.modalBackgroundColor ?? sheetTheme.backgroundColor,
             elevation: elevation ?? sheetTheme.modalElevation ?? sheetTheme.elevation,
@@ -484,11 +486,11 @@ class _ModalBottomSheetRoute<T> extends PopupRoute<T> {
             clipBehavior: clipBehavior,
             isScrollControlled: isScrollControlled,
             enableDrag: enableDrag,
+          );
+        },
       ),
     );
-    if (theme != null)
-      bottomSheet = Theme(data: theme!, child: bottomSheet);
-    return bottomSheet;
+    return capturedThemes.wrap(bottomSheet);
   }
 }
 
@@ -667,9 +669,10 @@ Future<T?> showModalBottomSheet<T>({
   assert(debugCheckHasMediaQuery(context));
   assert(debugCheckHasMaterialLocalizations(context));
 
-  return Navigator.of(context, rootNavigator: useRootNavigator)!.push(_ModalBottomSheetRoute<T>(
+  final NavigatorState navigator = Navigator.of(context, rootNavigator: useRootNavigator)!;
+  return navigator.push(_ModalBottomSheetRoute<T>(
     builder: builder,
-    theme: Theme.of(context, shadowThemeOnly: true),
+    capturedThemes: InheritedTheme.capture(from: context, to: navigator.context),
     isScrollControlled: isScrollControlled,
     barrierLabel: MaterialLocalizations.of(context).modalBarrierDismissLabel,
     backgroundColor: backgroundColor,

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

@@ -241,8 +241,7 @@ class ButtonTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final ButtonTheme? ancestorTheme = context.findAncestorWidgetOfExactType<ButtonTheme>();
-    return identical(this, ancestorTheme) ? child : ButtonTheme.fromButtonThemeData(data: data, child: child);
+    return ButtonTheme.fromButtonThemeData(data: data, child: child);
   }
 
   @override

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

@@ -91,8 +91,7 @@ class ChipTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final ChipTheme? ancestorTheme = context.findAncestorWidgetOfExactType<ChipTheme>();
-    return identical(this, ancestorTheme) ? child : ChipTheme(data: data, child: child);
+    return ChipTheme(data: data, child: child);
   }
 
   @override

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

@@ -978,18 +978,12 @@ Future<T?> showDialog<T>({
   assert(useRootNavigator != null);
   assert(debugCheckHasMaterialLocalizations(context));
 
-  final ThemeData? theme = Theme.of(context, shadowThemeOnly: true);
+  final CapturedThemes themes = InheritedTheme.capture(from: context, to: Navigator.of(context, rootNavigator: useRootNavigator)!.context);
   return showGeneralDialog(
     context: context,
     pageBuilder: (BuildContext buildContext, Animation<double> animation, Animation<double> secondaryAnimation) {
       final Widget pageChild = child ?? Builder(builder: builder!);
-      Widget dialog = Builder(
-        builder: (BuildContext context) {
-          return theme != null
-            ? Theme(data: theme, child: pageChild)
-            : pageChild;
-        }
-      );
+      Widget dialog = themes.wrap(pageChild);
       if (useSafeArea) {
         dialog = SafeArea(child: dialog);
       }

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

@@ -166,8 +166,7 @@ class DividerTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final DividerTheme? ancestorTheme = context.findAncestorWidgetOfExactType<DividerTheme>();
-    return identical(this, ancestorTheme) ? child : DividerTheme(data: data, child: child);
+    return DividerTheme(data: data, child: child);
   }
 
   @override

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

@@ -402,7 +402,7 @@ class _DropdownRoute<T> extends PopupRoute<_DropdownRouteResult<T>> {
     required this.buttonRect,
     required this.selectedIndex,
     this.elevation = 8,
-    this.theme,
+    required this.capturedThemes,
     required this.style,
     this.barrierLabel,
     this.itemHeight,
@@ -415,7 +415,7 @@ class _DropdownRoute<T> extends PopupRoute<_DropdownRouteResult<T>> {
   final Rect buttonRect;
   final int selectedIndex;
   final int elevation;
-  final ThemeData? theme;
+  final CapturedThemes capturedThemes;
   final TextStyle style;
   final double? itemHeight;
   final Color? dropdownColor;
@@ -447,7 +447,7 @@ class _DropdownRoute<T> extends PopupRoute<_DropdownRouteResult<T>> {
           buttonRect: buttonRect,
           selectedIndex: selectedIndex,
           elevation: elevation,
-          theme: theme,
+          capturedThemes: capturedThemes,
           style: style,
           dropdownColor: dropdownColor,
         );
@@ -533,7 +533,7 @@ class _DropdownRoutePage<T> extends StatelessWidget {
     required this.buttonRect,
     required this.selectedIndex,
     this.elevation = 8,
-    this.theme,
+    required this.capturedThemes,
     this.style,
     required this.dropdownColor,
   }) : super(key: key);
@@ -545,7 +545,7 @@ class _DropdownRoutePage<T> extends StatelessWidget {
   final Rect buttonRect;
   final int selectedIndex;
   final int elevation;
-  final ThemeData? theme;
+  final CapturedThemes capturedThemes;
   final TextStyle? style;
   final Color? dropdownColor;
 
@@ -565,7 +565,7 @@ class _DropdownRoutePage<T> extends StatelessWidget {
     }
 
     final TextDirection? textDirection = Directionality.of(context);
-    Widget menu = _DropdownMenu<T>(
+    final Widget menu = _DropdownMenu<T>(
       route: route,
       padding: padding.resolve(textDirection),
       buttonRect: buttonRect,
@@ -573,9 +573,6 @@ class _DropdownRoutePage<T> extends StatelessWidget {
       dropdownColor: dropdownColor,
     );
 
-    if (theme != null)
-      menu = Theme(data: theme!, child: menu);
-
     return MediaQuery.removePadding(
       context: context,
       removeTop: true,
@@ -590,7 +587,7 @@ class _DropdownRoutePage<T> extends StatelessWidget {
               route: route,
               textDirection: textDirection,
             ),
-            child: menu,
+            child: capturedThemes.wrap(menu),
           );
         },
       ),
@@ -1207,6 +1204,7 @@ class _DropdownButtonState<T> extends State<DropdownButton<T>> with WidgetsBindi
       )
     ];
 
+    final NavigatorState navigator = Navigator.of(context)!;
     assert(_dropdownRoute == null);
     _dropdownRoute = _DropdownRoute<T>(
       items: menuItems,
@@ -1214,14 +1212,14 @@ class _DropdownButtonState<T> extends State<DropdownButton<T>> with WidgetsBindi
       padding: _kMenuItemPadding.resolve(textDirection),
       selectedIndex: _selectedIndex ?? 0,
       elevation: widget.elevation,
-      theme: Theme.of(context, shadowThemeOnly: true),
+      capturedThemes: InheritedTheme.capture(from: context, to: navigator.context),
       style: _textStyle!,
       barrierLabel: MaterialLocalizations.of(context).modalBarrierDismissLabel,
       itemHeight: widget.itemHeight,
       dropdownColor: widget.dropdownColor,
     );
 
-    Navigator.push(context, _dropdownRoute!).then<void>((_DropdownRouteResult<T>? newValue) {
+    navigator.push(_dropdownRoute!).then<void>((_DropdownRouteResult<T>? newValue) {
       _removeDropdownRoute();
       if (!mounted || newValue == null)
         return;

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

@@ -116,8 +116,7 @@ class ElevatedButtonTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final ElevatedButtonTheme? ancestorTheme = context.findAncestorWidgetOfExactType<ElevatedButtonTheme>();
-    return identical(this, ancestorTheme) ? child : ElevatedButtonTheme(data: data, child: child);
+    return ElevatedButtonTheme(data: data, child: child);
   }
 
   @override

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

@@ -145,8 +145,7 @@ class ListTileTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final ListTileTheme? ancestorTheme = context.findAncestorWidgetOfExactType<ListTileTheme>();
-    return identical(this, ancestorTheme) ? child : ListTileTheme(
+    return ListTileTheme(
       dense: dense,
       shape: shape,
       style: style,

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

@@ -207,8 +207,7 @@ class NavigationRailTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final NavigationRailTheme? ancestorTheme = context.findAncestorWidgetOfExactType<NavigationRailTheme>();
-    return identical(this, ancestorTheme) ? child : NavigationRailTheme(data: data, child: child);
+    return NavigationRailTheme(data: data, child: child);
   }
 
   @override

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

@@ -116,8 +116,7 @@ class OutlinedButtonTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final OutlinedButtonTheme? ancestorTheme = context.findAncestorWidgetOfExactType<OutlinedButtonTheme>();
-    return identical(this, ancestorTheme) ? child : OutlinedButtonTheme(data: data, child: child);
+    return OutlinedButtonTheme(data: data, child: child);
   }
 
   @override

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

@@ -690,14 +690,11 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
     required this.items,
     this.initialValue,
     this.elevation,
-    this.theme,
-    required this.popupMenuTheme,
     required this.barrierLabel,
     this.semanticLabel,
     this.shape,
     this.color,
-    required this.showMenuContext,
-    required this.captureInheritedThemes,
+    required this.capturedThemes,
   }) : itemSizes = List<Size?>.filled(items.length, null);
 
   final RelativeRect position;
@@ -705,13 +702,10 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
   final List<Size?> itemSizes;
   final T? initialValue;
   final double? elevation;
-  final ThemeData? theme;
   final String? semanticLabel;
   final ShapeBorder? shape;
   final Color? color;
-  final PopupMenuThemeData popupMenuTheme;
-  final BuildContext showMenuContext;
-  final bool captureInheritedThemes;
+  final CapturedThemes capturedThemes;
 
   @override
   Animation<double> createAnimation() {
@@ -745,16 +739,7 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
       }
     }
 
-    Widget menu = _PopupMenu<T>(route: this, semanticLabel: semanticLabel);
-    if (captureInheritedThemes) {
-      menu = InheritedTheme.captureAll(showMenuContext, menu);
-    } else {
-      // For the sake of backwards compatibility. An (unlikely) app that relied
-      // on having menus only inherit from the material Theme could set
-      // captureInheritedThemes to false and get the original behavior.
-      if (theme != null)
-        menu = Theme(data: theme!, child: menu);
-    }
+    final Widget menu = _PopupMenu<T>(route: this, semanticLabel: semanticLabel);
 
     return SafeArea(
       child: Builder(
@@ -766,7 +751,7 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
               selectedItemIndex,
               Directionality.of(context)!,
             ),
-            child: menu,
+            child: capturedThemes.wrap(menu),
           );
         },
       ),
@@ -838,14 +823,12 @@ Future<T?> showMenu<T>({
   String? semanticLabel,
   ShapeBorder? shape,
   Color? color,
-  bool captureInheritedThemes = true,
   bool useRootNavigator = false,
 }) {
   assert(context != null);
   assert(position != null);
   assert(useRootNavigator != null);
   assert(items != null && items.isNotEmpty);
-  assert(captureInheritedThemes != null);
   assert(debugCheckHasMaterialLocalizations(context));
 
   switch (Theme.of(context)!.platform) {
@@ -859,19 +842,17 @@ Future<T?> showMenu<T>({
       semanticLabel ??= MaterialLocalizations.of(context).popupMenuLabel;
   }
 
-  return Navigator.of(context, rootNavigator: useRootNavigator)!.push(_PopupMenuRoute<T>(
+  final NavigatorState navigator = Navigator.of(context, rootNavigator: useRootNavigator)!;
+  return navigator.push(_PopupMenuRoute<T>(
     position: position,
     items: items,
     initialValue: initialValue,
     elevation: elevation,
     semanticLabel: semanticLabel,
-    theme: Theme.of(context, shadowThemeOnly: true),
-    popupMenuTheme: PopupMenuTheme.of(context),
     barrierLabel: MaterialLocalizations.of(context).modalBarrierDismissLabel,
     shape: shape,
     color: color,
-    showMenuContext: context,
-    captureInheritedThemes: captureInheritedThemes,
+    capturedThemes: InheritedTheme.capture(from: context, to: navigator.context),
   ));
 }
 
@@ -964,11 +945,9 @@ class PopupMenuButton<T> extends StatefulWidget {
     this.enabled = true,
     this.shape,
     this.color,
-    this.captureInheritedThemes = true,
   }) : assert(itemBuilder != null),
        assert(offset != null),
        assert(enabled != null),
-       assert(captureInheritedThemes != null),
        assert(!(child != null && icon != null),
            'You can only pass [child] or [icon], not both.'),
        super(key: key);
@@ -1050,11 +1029,6 @@ class PopupMenuButton<T> extends StatefulWidget {
   /// Theme.of(context).cardColor is used.
   final Color? color;
 
-  /// If true (the default) then the menu will be wrapped with copies
-  /// of the [InheritedTheme]s, like [Theme] and [PopupMenuTheme], which
-  /// are defined above the [BuildContext] where the menu is shown.
-  final bool captureInheritedThemes;
-
   @override
   PopupMenuButtonState<T> createState() => PopupMenuButtonState<T>();
 }
@@ -1094,7 +1068,6 @@ class PopupMenuButtonState<T> extends State<PopupMenuButton<T>> {
         position: position,
         shape: widget.shape ?? popupMenuTheme.shape,
         color: widget.color ?? popupMenuTheme.color,
-        captureInheritedThemes: widget.captureInheritedThemes,
       )
       .then<void>((T? newValue) {
         if (!mounted)

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

@@ -152,8 +152,7 @@ class PopupMenuTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final PopupMenuTheme? ancestorTheme = context.findAncestorWidgetOfExactType<PopupMenuTheme>();
-    return identical(this, ancestorTheme) ? child : PopupMenuTheme(data: data, child: child);
+    return PopupMenuTheme(data: data, child: child);
   }
 
   @override

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

@@ -117,8 +117,7 @@ class SliderTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final SliderTheme? ancestorTheme = context.findAncestorWidgetOfExactType<SliderTheme>();
-    return identical(this, ancestorTheme) ? child : SliderTheme(data: data, child: child);
+    return SliderTheme(data: data, child: child);
   }
 
   @override

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

@@ -116,8 +116,7 @@ class TextButtonTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final TextButtonTheme? ancestorTheme = context.findAncestorWidgetOfExactType<TextButtonTheme>();
-    return identical(this, ancestorTheme) ? child : TextButtonTheme(data: data, child: child);
+    return TextButtonTheme(data: data, child: child);
   }
 
   @override

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

@@ -157,8 +157,7 @@ class TextSelectionTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final TextSelectionTheme? ancestorTheme = context.findAncestorWidgetOfExactType<TextSelectionTheme>();
-    return identical(this, ancestorTheme) ? child : TextSelectionTheme(data: data, child: child);
+    return TextSelectionTheme(data: data, child: child);
   }
 
   @override

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

@@ -176,8 +176,7 @@ class _InheritedTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final _InheritedTheme? ancestorTheme = context.findAncestorWidgetOfExactType<_InheritedTheme>();
-    return identical(this, ancestorTheme) ? child : Theme(data: theme.data, child: child);
+    return Theme(data: theme.data, child: child);
   }
 
   @override

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

@@ -385,8 +385,7 @@ class TimePickerTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final TimePickerTheme? ancestorTheme = context.findAncestorWidgetOfExactType<TimePickerTheme>();
-    return identical(this, ancestorTheme) ? child : TimePickerTheme(data: data, child: child);
+    return TimePickerTheme(data: data, child: child);
   }
 
   @override

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

@@ -271,8 +271,7 @@ class ToggleButtonsTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final ToggleButtonsTheme? ancestorTheme = context.findAncestorWidgetOfExactType<ToggleButtonsTheme>();
-    return identical(this, ancestorTheme) ? child : ToggleButtonsTheme(data: data, child: child);
+    return ToggleButtonsTheme(data: data, child: child);
   }
 
   @override

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

@@ -244,8 +244,7 @@ class TooltipTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final TooltipTheme? ancestorTheme = context.findAncestorWidgetOfExactType<TooltipTheme>();
-    return identical(this, ancestorTheme) ? child : TooltipTheme(data: data, child: child);
+    return TooltipTheme(data: data, child: child);
   }
 
   @override

packages/flutter/lib/src/widgets/icon_theme.dart

@@ -79,8 +79,7 @@ class IconTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final IconTheme? iconTheme = context.findAncestorWidgetOfExactType<IconTheme>();
-    return identical(this, iconTheme) ? child : IconTheme(data: data, child: child);
+    return IconTheme(data: data, child: child);
   }
 
   @override

packages/flutter/lib/src/widgets/inherited_theme.dart

@@ -9,23 +9,21 @@ import 'framework.dart';
 /// An [InheritedWidget] that defines visual properties like colors
 /// and text styles, which the [child]'s subtree depends on.
 ///
-/// The [wrap] method is used by [captureAll] to construct a widget
-/// that will wrap a child in all of the inherited themes which
-/// are present in a build context but are not present in the
-/// context that the returned widget is eventually built in.
+/// The [wrap] method is used by [captureAll] and [CapturedThemes.wrap] to
+/// construct a widget that will wrap a child in all of the inherited themes
+/// which are present in a specified part of the widget tree.
 ///
-/// A widget that's shown in a different context from the one it's
-/// built in, like the contents of a new route or an overlay, will
-/// be able to depend on inherited widget ancestors of the context
-/// it's built in.
+/// A widget that's shown in a different context from the one it's built in,
+/// like the contents of a new route or an overlay, will be able to see the
+/// ancestor inherited themes of the context it was built in.
 ///
 /// {@tool dartpad --template=freeform}
-/// This example demonstrates how `InheritedTheme.captureAll()` can be used
+/// This example demonstrates how `InheritedTheme.capture()` can be used
 /// to wrap the contents of a new route with the inherited themes that
-/// are present when the route is built - but are not present when route
+/// are present when the route was built - but are not present when route
 /// is actually shown.
 ///
-/// If the same code is run without `InheritedTheme.captureAll(), the
+/// If the same code is run without `InheritedTheme.capture(), the
 /// new route's Text widget will inherit the "something must be wrong"
 /// fallback text style, rather than the default text style defined in MyApp.
 ///
@@ -43,19 +41,25 @@ import 'framework.dart';
 /// class MyAppBody extends StatelessWidget {
 ///   @override
 ///   Widget build(BuildContext context) {
+///     final NavigatorState navigator = Navigator.of(context);
+///     // This InheritedTheme.capture() saves references to themes that are
+///     // found above the context provided to this widget's build method
+///     // excluding themes are are found above the navigator. Those themes do
+///     // not have to be captured, because they will already be visible from
+///     // the new route pushed onto said navigator.
+///     // Themes are captured outside of the route's builder because when the
+///     // builder executes, the context may not be valid anymore.
+///     final CapturedThemes themes = InheritedTheme.capture(from: context, to: navigator.context);
 ///     return GestureDetector(
 ///       onTap: () {
 ///         Navigator.of(context).push(
 ///           MaterialPageRoute(
 ///             builder: (BuildContext _) {
-///               // InheritedTheme.captureAll() saves references to themes that
-///               // are found above the context provided to this widget's build
-///               // method, notably the DefaultTextStyle defined in MyApp. The
-///               // context passed to the MaterialPageRoute's builder is not used,
-///               // because its ancestors are above MyApp's home.
-///               return InheritedTheme.captureAll(context, Container(
+///               // Wrap the actual child of the route in the previously
+///               // captured themes.
+///               return themes.wrap(Container(
 ///                 alignment: Alignment.center,
-///                 color: Theme.of(context).colorScheme.surface,
+///                 color: Colors.white,
 ///                 child: Text('Hello World'),
 ///               ));
 ///             },
@@ -95,27 +99,72 @@ abstract class InheritedTheme extends InheritedWidget {
 
   /// Return a copy of this inherited theme with the specified [child].
   ///
-  /// If the identical inherited theme is already visible from [context] then
-  /// just return the [child].
-  ///
   /// This implementation for [TooltipTheme] is typical:
+  ///
   /// ```dart
   /// Widget wrap(BuildContext context, Widget child) {
-  ///   final TooltipTheme ancestorTheme = context.findAncestorWidgetOfExactType<TooltipTheme>());
-  ///   return identical(this, ancestorTheme) ? child : TooltipTheme(data: data, child: child);
+  ///   return TooltipTheme(data: data, child: child);
   /// }
   /// ```
   Widget wrap(BuildContext context, Widget child);
 
-  /// Returns a widget that will [wrap] child in all of the inherited themes
-  /// which are visible from [context].
-  static Widget captureAll(BuildContext context, Widget child) {
+  /// Returns a widget that will [wrap] `child` in all of the inherited themes
+  /// which are present between `context` and the specified `to`
+  /// [BuildContext].
+  ///
+  /// The `to` context must be an ancestor of `context`. If `to` is not
+  /// specified, all inherited themes up to the root of the widget tree are
+  /// captured.
+  ///
+  /// After calling this method, the themes present between `context` and `to`
+  /// are frozen for the provided `child`. If the themes (or their theme data)
+  /// change in the original subtree, those changes will not be visible to
+  /// the wrapped `child` - unless this method is called again to re-wrap the
+  /// child.
+  static Widget captureAll(BuildContext context, Widget child, {BuildContext? to}) {
     assert(child != null);
     assert(context != null);
 
+    return capture(from: context, to: to).wrap(child);
+  }
+
+  /// Returns a [CapturedThemes] object that includes all the [InheritedTheme]s
+  /// between the given `from` and `to` [BuildContext]s.
+  ///
+  /// The `to` context must be an ancestor of the `from` context. If `to` is
+  /// null, all ancestor inherited themes of `from` up to the root of the
+  /// widget tree are captured.
+  ///
+  /// After calling this method, the themes present between `from` and `to` are
+  /// frozen in the returned [CapturedThemes] object. If the themes (or their
+  /// theme data) change in the original subtree, those changes will not be
+  /// applied to the themes captured in the [CapturedThemes] object - unless
+  /// this method is called again to re-capture the updated themes.
+  ///
+  /// To wrap a [Widget] in the captured themes, call [CapturedThemes.wrap].
+  static CapturedThemes capture({ required BuildContext from, required BuildContext? to }) {
+    assert(from != null);
+
+    if (from == to) {
+      // Nothing to capture.
+      return CapturedThemes._(const <InheritedTheme>[]);
+    }
+
     final List<InheritedTheme> themes = <InheritedTheme>[];
     final Set<Type> themeTypes = <Type>{};
-    context.visitAncestorElements((Element ancestor) {
+    late bool debugDidFindAncestor;
+    assert(() {
+      debugDidFindAncestor = to == null;
+      return true;
+    }());
+    from.visitAncestorElements((Element ancestor) {
+      if (ancestor == to) {
+        assert(() {
+          debugDidFindAncestor = true;
+          return true;
+        }());
+        return false;
+      }
       if (ancestor is InheritedElement && ancestor.widget is InheritedTheme) {
         final InheritedTheme theme = ancestor.widget as InheritedTheme;
         final Type themeType = theme.runtimeType;
@@ -130,7 +179,23 @@ abstract class InheritedTheme extends InheritedWidget {
       return true;
     });
 
-    return _CaptureAll(themes: themes, child: child);
+    assert(debugDidFindAncestor, 'The provided `to` context must be an ancestor of the `from` context.');
+    return CapturedThemes._(themes);
+  }
+}
+
+/// Stores a list of captured [InheritedTheme]s that can be wrapped around a
+/// child [Widget].
+///
+/// Used as return type by [InheritedTheme.capture].
+class CapturedThemes {
+  CapturedThemes._(this._themes);
+
+  final List<InheritedTheme> _themes;
+
+  /// Wraps a `child` [Widget] in the [InheritedTheme]s captured in this object.
+  Widget wrap(Widget child) {
+    return _CaptureAll(themes: _themes, child: child);
   }
 }
 

packages/flutter/lib/src/widgets/text.dart

@@ -181,8 +181,7 @@ class DefaultTextStyle extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final DefaultTextStyle? defaultTextStyle = context.findAncestorWidgetOfExactType<DefaultTextStyle>();
-    return identical(this, defaultTextStyle) ? child : DefaultTextStyle(
+    return DefaultTextStyle(
       style: style,
       textAlign: textAlign,
       softWrap: softWrap,
@@ -266,8 +265,7 @@ class DefaultTextHeightBehavior extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final DefaultTextHeightBehavior? defaultTextHeightBehavior = context.findAncestorWidgetOfExactType<DefaultTextHeightBehavior>();
-    return identical(this, defaultTextHeightBehavior) ? child : DefaultTextHeightBehavior(
+    return DefaultTextHeightBehavior(
       textHeightBehavior: textHeightBehavior,
       child: child,
     );

packages/flutter/test/material/inherited_theme_test.dart

@@ -96,7 +96,6 @@ void main() {
   testWidgets('PopupMenuTheme.wrap()', (WidgetTester tester) async {
     const double menuFontSize = 24;
     const Color menuTextColor = Color(0xFF0000FF);
-    bool captureInheritedThemes = true;
 
     Widget buildFrame() {
       return MaterialApp(
@@ -112,7 +111,6 @@ void main() {
                 // The appearance of the menu items' text is defined by the
                 // PopupMenuTheme defined above. Popup menus use
                 // InheritedTheme.captureAll() by default.
-                captureInheritedThemes: captureInheritedThemes,
                 child: const Text('show popupmenu'),
                 onSelected: (int result) { },
                 itemBuilder: (BuildContext context) {
@@ -146,17 +144,6 @@ void main() {
     // Dismiss the menu
     await tester.tap(find.text('One'));
     await tester.pumpAndSettle(); // menu route animation
-
-    // Defeat the default support for capturing the PopupMenuTheme.
-    captureInheritedThemes = false;
-    await tester.pumpWidget(buildFrame());
-
-    await tester.tap(find.text('show popupmenu'));
-    await tester.pumpAndSettle(); // menu route animation
-    expect(itemTextStyle('One').fontSize, isNot(menuFontSize));
-    expect(itemTextStyle('One').color,  isNot(menuTextColor));
-    expect(itemTextStyle('Two').fontSize, isNot(menuFontSize));
-    expect(itemTextStyle('Two').color,  isNot(menuTextColor));
   });
 
   testWidgets('BannerTheme.wrap()', (WidgetTester tester) async {