Remove `brightness` from `AppBar`/`SliverAppBar`/`AppBarTheme`/`AppBarTheme.copyWith` (#120575)

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

@@ -194,11 +194,6 @@ class AppBar extends StatefulWidget implements PreferredSizeWidget {
     this.shape,
     this.backgroundColor,
     this.foregroundColor,
-    @Deprecated(
-      'This property is no longer used, please use systemOverlayStyle instead. '
-      'This feature was deprecated after v2.4.0-0.0.pre.',
-    )
-    this.brightness,
     this.iconTheme,
     this.actionsIconTheme,
     this.primary = true,
@@ -499,7 +494,7 @@ class AppBar extends StatefulWidget implements PreferredSizeWidget {
   /// If null, then the [AppBarTheme.backgroundColor] is used. If that value is also
   /// null, then [AppBar] uses the overall theme's [ColorScheme.primary] if the
   /// overall theme's brightness is [Brightness.light], and [ColorScheme.surface]
-  /// if the overall theme's [brightness] is [Brightness.dark].
+  /// if the overall theme's brightness is [Brightness.dark].
   ///
   /// If this color is a [MaterialStateColor] it will be resolved against
   /// [MaterialState.scrolledUnder] when the content of the app's
@@ -525,7 +520,7 @@ class AppBar extends StatefulWidget implements PreferredSizeWidget {
   /// value is also null, then [AppBar] uses the overall theme's
   /// [ColorScheme.onPrimary] if the overall theme's brightness is
   /// [Brightness.light], and [ColorScheme.onSurface] if the overall
-  /// theme's [brightness] is [Brightness.dark].
+  /// theme's brightness is [Brightness.dark].
   ///
   /// This color is used to configure [DefaultTextStyle] that contains
   /// the toolbar's children, and the default [IconTheme] widgets that
@@ -543,38 +538,6 @@ class AppBar extends StatefulWidget implements PreferredSizeWidget {
   ///    is light or dark.
   final Color? foregroundColor;
 
-  /// {@template flutter.material.appbar.brightness}
-  /// This property is deprecated, please use [systemOverlayStyle] instead.
-  ///
-  /// Determines the brightness of the [SystemUiOverlayStyle]: for
-  /// [Brightness.dark], [SystemUiOverlayStyle.light] is used and for
-  /// [Brightness.light], [SystemUiOverlayStyle.dark] is used.
-  ///
-  /// If this value is null then [AppBarTheme.brightness] is used
-  /// and if that's null then overall theme's brightness is used.
-  ///
-  /// The AppBar is built within a `AnnotatedRegion<SystemUiOverlayStyle>`
-  /// which causes [SystemChrome.setSystemUIOverlayStyle] to be called
-  /// automatically. Apps should not enclose the AppBar with
-  /// their own [AnnotatedRegion].
-  /// {@endtemplate}
-  ///
-  /// See also:
-  ///
-  ///  * [Theme.of], which returns the current overall Material theme as
-  ///    a [ThemeData].
-  ///  * [ThemeData.colorScheme], the thirteen colors that most Material widget
-  ///    default colors are based on.
-  ///  * [ColorScheme.brightness], which indicates if the overall [Theme]
-  ///    is light or dark.
-  ///  * [backwardsCompatibility], which forces AppBar to use this
-  ///    obsolete property.
-  @Deprecated(
-    'This property is no longer used, please use systemOverlayStyle instead. '
-    'This feature was deprecated after v2.4.0-0.0.pre.',
-  )
-  final Brightness? brightness;
-
   /// {@template flutter.material.appbar.iconTheme}
   /// The color, opacity, and size to use for toolbar icons.
   ///
@@ -692,8 +655,7 @@ class AppBar extends StatefulWidget implements PreferredSizeWidget {
   /// This property is deprecated and is false by default.
   ///
   /// If true, preserves the original defaults for the [backgroundColor],
-  /// [iconTheme], [actionsIconTheme] properties, and the original use of
-  /// the [brightness] property.
+  /// [iconTheme], [actionsIconTheme] properties.
   ///
   /// If this property is null, then [AppBarTheme.backwardsCompatibility] of
   /// [ThemeData.appBarTheme] is used. If that is also null, the default
@@ -1212,11 +1174,9 @@ class _AppBarState extends State<AppBar> {
     }
 
     final SystemUiOverlayStyle overlayStyle = backwardsCompatibility
-      ? _systemOverlayStyleForBrightness(
-          widget.brightness
-          ?? appBarTheme.brightness
-          ?? ThemeData.estimateBrightnessForColor(backgroundColor),
-        )
+      ? widget.systemOverlayStyle
+        ?? appBarTheme.systemOverlayStyle
+        ?? _systemOverlayStyleForBrightness(ThemeData.estimateBrightnessForColor(backgroundColor))
       : widget.systemOverlayStyle
         ?? appBarTheme.systemOverlayStyle
         ?? defaults.systemOverlayStyle
@@ -1269,7 +1229,6 @@ class _SliverAppBarDelegate extends SliverPersistentHeaderDelegate {
     required this.forceElevated,
     required this.backgroundColor,
     required this.foregroundColor,
-    required this.brightness,
     required this.iconTheme,
     required this.actionsIconTheme,
     required this.primary,
@@ -1309,7 +1268,6 @@ class _SliverAppBarDelegate extends SliverPersistentHeaderDelegate {
   final bool forceElevated;
   final Color? backgroundColor;
   final Color? foregroundColor;
-  final Brightness? brightness;
   final IconThemeData? iconTheme;
   final IconThemeData? actionsIconTheme;
   final bool primary;
@@ -1385,7 +1343,6 @@ class _SliverAppBarDelegate extends SliverPersistentHeaderDelegate {
         surfaceTintColor: surfaceTintColor,
         backgroundColor: backgroundColor,
         foregroundColor: foregroundColor,
-        brightness: brightness,
         iconTheme: iconTheme,
         actionsIconTheme: actionsIconTheme,
         primary: primary,
@@ -1420,7 +1377,6 @@ class _SliverAppBarDelegate extends SliverPersistentHeaderDelegate {
         || shadowColor != oldDelegate.shadowColor
         || backgroundColor != oldDelegate.backgroundColor
         || foregroundColor != oldDelegate.foregroundColor
-        || brightness != oldDelegate.brightness
         || iconTheme != oldDelegate.iconTheme
         || actionsIconTheme != oldDelegate.actionsIconTheme
         || primary != oldDelegate.primary
@@ -1555,11 +1511,6 @@ class SliverAppBar extends StatefulWidget {
     this.forceElevated = false,
     this.backgroundColor,
     this.foregroundColor,
-    @Deprecated(
-      'This property is no longer used, please use systemOverlayStyle instead. '
-      'This feature was deprecated after v2.4.0-0.0.pre.',
-    )
-    this.brightness,
     this.iconTheme,
     this.actionsIconTheme,
     this.primary = true,
@@ -1865,15 +1816,6 @@ class SliverAppBar extends StatefulWidget {
   /// This property is used to configure an [AppBar].
   final Color? foregroundColor;
 
-  /// {@macro flutter.material.appbar.brightness}
-  ///
-  /// This property is used to configure an [AppBar].
-  @Deprecated(
-    'This property is no longer used, please use systemOverlayStyle instead. '
-    'This feature was deprecated after v2.4.0-0.0.pre.',
-  )
-  final Brightness? brightness;
-
   /// {@macro flutter.material.appbar.iconTheme}
   ///
   /// This property is used to configure an [AppBar].
@@ -2149,7 +2091,6 @@ class _SliverAppBarState extends State<SliverAppBar> with TickerProviderStateMix
           forceElevated: widget.forceElevated,
           backgroundColor: widget.backgroundColor,
           foregroundColor: widget.foregroundColor,
-          brightness: widget.brightness,
           iconTheme: widget.iconTheme,
           actionsIconTheme: widget.actionsIconTheme,
           primary: widget.primary,

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

@@ -27,11 +27,6 @@ import 'theme.dart';
 class AppBarTheme with Diagnosticable {
   /// Creates a theme that can be used for [ThemeData.appBarTheme].
   const AppBarTheme({
-    @Deprecated(
-      'This property is no longer used, please use systemOverlayStyle instead. '
-      'This feature was deprecated after v2.4.0-0.0.pre.',
-    )
-    this.brightness,
     Color? color,
     Color? backgroundColor,
     this.foregroundColor,
@@ -59,24 +54,6 @@ class AppBarTheme with Diagnosticable {
        ),
        backgroundColor = backgroundColor ?? color;
 
-  /// This property is deprecated, please use [systemOverlayStyle] instead.
-  ///
-  /// Overrides the default value of the obsolete [AppBar.brightness]
-  /// property which implicitly defines [AppBar.systemOverlayStyle] in
-  /// all descendant [AppBar] widgets.
-  ///
-  /// See also:
-  ///
-  ///  * [systemOverlayStyle], which overrides the default value of
-  ///    [AppBar.systemOverlayStyle] in all descendant [AppBar] widgets.
-  ///  * [AppBar.backwardsCompatibility], which forces [AppBar] to depend
-  ///    on this obsolete property.
-  @Deprecated(
-    'This property is no longer used, please use systemOverlayStyle instead. '
-    'This feature was deprecated after v2.4.0-0.0.pre.',
-  )
-  final Brightness? brightness;
-
   /// This property is deprecated, please use [backgroundColor] instead.
   ///
   /// Obsolete property that overrides the default value of
@@ -214,11 +191,6 @@ class AppBarTheme with Diagnosticable {
   /// new values.
   AppBarTheme copyWith({
     IconThemeData? actionsIconTheme,
-    @Deprecated(
-      'This property is no longer used, please use systemOverlayStyle instead. '
-      'This feature was deprecated after v2.4.0-0.0.pre.',
-    )
-    Brightness? brightness,
     Color? color,
     Color? backgroundColor,
     Color? foregroundColor,
@@ -245,7 +217,6 @@ class AppBarTheme with Diagnosticable {
       'The color and backgroundColor parameters mean the same thing. Only specify one.',
     );
     return AppBarTheme(
-      brightness: brightness ?? this.brightness,
       backgroundColor: backgroundColor ?? color ?? this.backgroundColor,
       foregroundColor: foregroundColor ?? this.foregroundColor,
       elevation: elevation ?? this.elevation,
@@ -277,7 +248,6 @@ class AppBarTheme with Diagnosticable {
   /// {@macro dart.ui.shadow.lerp}
   static AppBarTheme lerp(AppBarTheme? a, AppBarTheme? b, double t) {
     return AppBarTheme(
-      brightness: t < 0.5 ? a?.brightness : b?.brightness,
       backgroundColor: Color.lerp(a?.backgroundColor, b?.backgroundColor, t),
       foregroundColor: Color.lerp(a?.foregroundColor, b?.foregroundColor, t),
       elevation: lerpDouble(a?.elevation, b?.elevation, t),
@@ -299,7 +269,6 @@ class AppBarTheme with Diagnosticable {
 
   @override
   int get hashCode => Object.hash(
-    brightness,
     backgroundColor,
     foregroundColor,
     elevation,
@@ -327,7 +296,6 @@ class AppBarTheme with Diagnosticable {
       return false;
     }
     return other is AppBarTheme
-        && other.brightness == brightness
         && other.backgroundColor == backgroundColor
         && other.foregroundColor == foregroundColor
         && other.elevation == elevation
@@ -349,7 +317,6 @@ class AppBarTheme with Diagnosticable {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<Brightness>('brightness', brightness, defaultValue: null));
     properties.add(ColorProperty('backgroundColor', backgroundColor, defaultValue: null));
     properties.add(ColorProperty('foregroundColor', foregroundColor, defaultValue: null));
     properties.add(DiagnosticsProperty<double>('elevation', elevation, defaultValue: null));

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

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 
 import 'app_bar.dart';
@@ -231,7 +232,9 @@ abstract class SearchDelegate<T> {
     final ColorScheme colorScheme = theme.colorScheme;
     return theme.copyWith(
       appBarTheme: AppBarTheme(
-        brightness: colorScheme.brightness,
+        systemOverlayStyle: colorScheme.brightness == Brightness.dark
+          ? SystemUiOverlayStyle.light
+          : SystemUiOverlayStyle.dark,
         backgroundColor: colorScheme.brightness == Brightness.dark ? Colors.grey[900] : Colors.white,
         iconTheme: theme.primaryIconTheme.copyWith(color: Colors.grey),
         titleTextStyle: theme.textTheme.titleLarge,

packages/flutter/lib/src/services/system_chrome.dart

@@ -505,7 +505,7 @@ class SystemChrome {
   /// page, consider calling when pushing/popping a new [PageRoute].
   ///
   /// However, the [AppBar] widget automatically sets the system overlay style
-  /// based on its [AppBar.brightness], so configure that instead of calling
+  /// based on its [AppBar.systemOverlayStyle], so configure that instead of calling
   /// this method directly. Likewise, do the same for [CupertinoNavigationBar]
   /// via [CupertinoNavigationBar.backgroundColor].
   ///

packages/flutter/test/material/app_bar_theme_test.dart

@@ -87,7 +87,7 @@ void main() {
     final RichText actionIconText = _getAppBarIconRichText(tester);
     final DefaultTextStyle text = _getAppBarText(tester);
 
-    expect(SystemChrome.latestStyle!.statusBarBrightness, appBarTheme.brightness);
+    expect(SystemChrome.latestStyle!.statusBarBrightness, Brightness.light);
     expect(widget.color, appBarTheme.backgroundColor);
     expect(widget.elevation, appBarTheme.elevation);
     expect(widget.shadowColor, appBarTheme.shadowColor);
@@ -167,7 +167,6 @@ void main() {
         home: Scaffold(
           appBar: AppBar(
             backgroundColor: color,
-            brightness: brightness,
             systemOverlayStyle: systemOverlayStyle,
             elevation: elevation,
             shadowColor: shadowColor,
@@ -246,7 +245,7 @@ void main() {
     final RichText actionIconText = _getAppBarIconRichText(tester);
     final DefaultTextStyle text = _getAppBarText(tester);
 
-    expect(SystemChrome.latestStyle!.statusBarBrightness, appBarTheme.brightness);
+    expect(SystemChrome.latestStyle!.statusBarBrightness, Brightness.light);
     expect(widget.color, appBarTheme.backgroundColor);
     expect(widget.elevation, appBarTheme.elevation);
     expect(widget.shadowColor, appBarTheme.shadowColor);
@@ -804,7 +803,6 @@ void main() {
   testWidgets('AppBarTheme implements debugFillProperties', (WidgetTester tester) async {
     final DiagnosticPropertiesBuilder builder = DiagnosticPropertiesBuilder();
     const AppBarTheme(
-      brightness: Brightness.dark,
       backgroundColor: Color(0xff000001),
       elevation: 8.0,
       shadowColor: Color(0xff000002),
@@ -819,7 +817,6 @@ void main() {
       .toList();
 
     expect(description, <String>[
-      'brightness: Brightness.dark',
       'backgroundColor: Color(0xff000001)',
       'elevation: 8.0',
       'shadowColor: Color(0xff000002)',
@@ -837,7 +834,7 @@ void main() {
 }
 
 AppBarTheme _appBarTheme() {
-  const Brightness brightness = Brightness.light;
+  const SystemUiOverlayStyle systemOverlayStyle = SystemUiOverlayStyle.dark;
   const Color backgroundColor = Colors.lightBlue;
   const double elevation = 6.0;
   const Color shadowColor = Colors.red;
@@ -846,7 +843,7 @@ AppBarTheme _appBarTheme() {
   const IconThemeData actionsIconThemeData = IconThemeData(color: Colors.pink);
   return const AppBarTheme(
     actionsIconTheme: actionsIconThemeData,
-    brightness: brightness,
+    systemOverlayStyle: systemOverlayStyle,
     backgroundColor: backgroundColor,
     elevation: elevation,
     shadowColor: shadowColor,