Updated `ProgressIndicator` to M3 (#112139)

dev/tools/gen_defaults/bin/gen_defaults.dart

@@ -31,6 +31,7 @@ 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/progress_indicator_template.dart';
 import 'package:gen_defaults/radio_template.dart';
 import 'package:gen_defaults/surface_tint.dart';
 import 'package:gen_defaults/switch_template.dart';
@@ -80,6 +81,8 @@ Future<void> main(List<String> args) async {
     'navigation_drawer.json',
     'navigation_rail.json',
     'palette.json',
+    'progress_indicator_circular.json',
+    'progress_indicator_linear.json',
     'radio_button.json',
     'segmented_button_outlined.json',
     'shape.json',
@@ -126,6 +129,7 @@ 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', '$materialLib/navigation_rail.dart', tokens).updateFile();
+  ProgressIndicatorTemplate('ProgressIndicator', '$materialLib/progress_indicator.dart', tokens).updateFile();
   RadioTemplate('Radio<T>', '$materialLib/radio.dart', tokens).updateFile();
   SurfaceTintTemplate('SurfaceTint', '$materialLib/elevation_overlay.dart', tokens).updateFile();
   SwitchTemplate('Switch', '$materialLib/switch.dart', tokens).updateFile();

dev/tools/gen_defaults/lib/progress_indicator_template.dart

+// 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 ProgressIndicatorTemplate extends TokenTemplate {
+  const ProgressIndicatorTemplate(super.blockName, super.fileName, super.tokens, {
+    super.colorSchemePrefix = '_colors.',
+  });
+
+  @override
+  String generate() => '''
+class _Circular${blockName}DefaultsM3 extends ProgressIndicatorThemeData {
+  _Circular${blockName}DefaultsM3(this.context);
+
+  final BuildContext context;
+  late final ColorScheme _colors = Theme.of(context).colorScheme;
+
+  static const double circularProgressIndicatorSize = ${tokens['md.comp.circular-progress-indicator.size']};
+
+  @override
+  Color get color => ${componentColor('md.comp.circular-progress-indicator.active-indicator')};
+}
+
+class _Linear${blockName}DefaultsM3 extends ProgressIndicatorThemeData {
+  _Linear${blockName}DefaultsM3(this.context);
+
+  final BuildContext context;
+  late final ColorScheme _colors = Theme.of(context).colorScheme;
+
+  @override
+  Color get color => ${componentColor('md.comp.linear-progress-indicator.active-indicator')};
+
+  @override
+  Color get linearTrackColor => ${componentColor('md.comp.linear-progress-indicator.track')};
+
+  @override
+  double get linearMinHeight => ${tokens['md.comp.linear-progress-indicator.track.height']};
+}
+''';
+}

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

@@ -108,11 +108,11 @@ abstract class ProgressIndicator extends StatefulWidget {
   /// {@endtemplate}
   final String? semanticsValue;
 
-  Color _getValueColor(BuildContext context) {
-    return
-      valueColor?.value ??
+  Color _getValueColor(BuildContext context, {Color? defaultColor}) {
+    return valueColor?.value ??
       color ??
       ProgressIndicatorTheme.of(context).color ??
+      defaultColor ??
       Theme.of(context).colorScheme.primary;
   }
 
@@ -331,12 +331,17 @@ class _LinearProgressIndicatorState extends State<LinearProgressIndicator> with
   }
 
   Widget _buildIndicator(BuildContext context, double animationValue, TextDirection textDirection) {
+    final ProgressIndicatorThemeData defaults = Theme.of(context).useMaterial3
+      ? _LinearProgressIndicatorDefaultsM3(context)
+      : _LinearProgressIndicatorDefaultsM2(context);
+
     final ProgressIndicatorThemeData indicatorTheme = ProgressIndicatorTheme.of(context);
-    final Color trackColor =
-      widget.backgroundColor ??
+    final Color trackColor = widget.backgroundColor ??
       indicatorTheme.linearTrackColor ??
-      Theme.of(context).colorScheme.background;
-    final double minHeight = widget.minHeight ?? indicatorTheme.linearMinHeight ?? 4.0;
+      defaults.linearTrackColor!;
+    final double minHeight = widget.minHeight ??
+      indicatorTheme.linearMinHeight ??
+      defaults.linearMinHeight!;
 
     return widget._buildSemanticsWrapper(
       context: context,
@@ -348,7 +353,7 @@ class _LinearProgressIndicatorState extends State<LinearProgressIndicator> with
         child: CustomPaint(
           painter: _LinearProgressIndicatorPainter(
             backgroundColor: trackColor,
-            valueColor: widget._getValueColor(context),
+            valueColor: widget._getValueColor(context, defaultColor: defaults.color),
             value: widget.value, // may be null
             animationValue: animationValue, // ignored if widget.value is not null
             textDirection: textDirection,
@@ -580,29 +585,44 @@ class _CircularProgressIndicatorState extends State<CircularProgressIndicator> w
   }
 
   Widget _buildMaterialIndicator(BuildContext context, double headValue, double tailValue, double offsetValue, double rotationValue) {
+    final ProgressIndicatorThemeData defaults = Theme.of(context).useMaterial3
+      ? _CircularProgressIndicatorDefaultsM3(context)
+      : _CircularProgressIndicatorDefaultsM2(context);
     final Color? trackColor = widget.backgroundColor ?? ProgressIndicatorTheme.of(context).circularTrackColor;
 
-    return widget._buildSemanticsWrapper(
-      context: context,
-      child: Container(
-        constraints: const BoxConstraints(
-          minWidth: _kMinCircularProgressIndicatorSize,
-          minHeight: _kMinCircularProgressIndicatorSize,
-        ),
-        child: CustomPaint(
-          painter: _CircularProgressIndicatorPainter(
-            backgroundColor: trackColor,
-            valueColor: widget._getValueColor(context),
-            value: widget.value, // may be null
-            headValue: headValue, // remaining arguments are ignored if widget.value is not null
-            tailValue: tailValue,
-            offsetValue: offsetValue,
-            rotationValue: rotationValue,
-            strokeWidth: widget.strokeWidth,
-          ),
+    Widget progressIndicator = Container(
+      constraints: const BoxConstraints(
+        minWidth: _kMinCircularProgressIndicatorSize,
+        minHeight: _kMinCircularProgressIndicatorSize,
+      ),
+      child: CustomPaint(
+        painter: _CircularProgressIndicatorPainter(
+          backgroundColor: trackColor,
+          valueColor: widget._getValueColor(context, defaultColor: defaults.color),
+          value: widget.value, // may be null
+          headValue: headValue, // remaining arguments are ignored if widget.value is not null
+          tailValue: tailValue,
+          offsetValue: offsetValue,
+          rotationValue: rotationValue,
+          strokeWidth: widget.strokeWidth,
         ),
       ),
     );
+
+    if (Theme.of(context).useMaterial3) {
+      progressIndicator = SizedBox(
+        height: _CircularProgressIndicatorDefaultsM3.circularProgressIndicatorSize,
+        width: _CircularProgressIndicatorDefaultsM3.circularProgressIndicatorSize,
+        child: Center(
+          child: progressIndicator
+        ),
+      );
+    }
+
+    return widget._buildSemanticsWrapper(
+      context: context,
+      child: progressIndicator,
+    );
   }
 
   Widget _buildAnimation() {
@@ -866,3 +886,69 @@ class _RefreshProgressIndicatorState extends _CircularProgressIndicatorState {
     );
   }
 }
+
+// Hand coded defaults based on Material Design 2.
+class _CircularProgressIndicatorDefaultsM2 extends ProgressIndicatorThemeData {
+  _CircularProgressIndicatorDefaultsM2(this.context);
+
+  final BuildContext context;
+  late final ColorScheme _colors = Theme.of(context).colorScheme;
+
+  @override
+  Color get color => _colors.primary;
+}
+
+class _LinearProgressIndicatorDefaultsM2 extends ProgressIndicatorThemeData {
+  _LinearProgressIndicatorDefaultsM2(this.context);
+
+  final BuildContext context;
+  late final ColorScheme _colors = Theme.of(context).colorScheme;
+
+  @override
+  Color get color => _colors.primary;
+
+  @override
+  Color get linearTrackColor => _colors.background;
+
+  @override
+  double get linearMinHeight => 4.0;
+}
+
+// BEGIN GENERATED TOKEN PROPERTIES - ProgressIndicator
+
+// 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 _CircularProgressIndicatorDefaultsM3 extends ProgressIndicatorThemeData {
+  _CircularProgressIndicatorDefaultsM3(this.context);
+
+  final BuildContext context;
+  late final ColorScheme _colors = Theme.of(context).colorScheme;
+
+  static const double circularProgressIndicatorSize = 48.0;
+
+  @override
+  Color get color => _colors.primary;
+}
+
+class _LinearProgressIndicatorDefaultsM3 extends ProgressIndicatorThemeData {
+  _LinearProgressIndicatorDefaultsM3(this.context);
+
+  final BuildContext context;
+  late final ColorScheme _colors = Theme.of(context).colorScheme;
+
+  @override
+  Color get color => _colors.primary;
+
+  @override
+  Color get linearTrackColor => _colors.surfaceVariant;
+
+  @override
+  double get linearMinHeight => 4.0;
+}
+
+// END GENERATED TOKEN PROPERTIES - ProgressIndicator

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

@@ -1266,6 +1266,7 @@ class ThemeData with Diagnosticable {
   ///   * Lists: [ListTile]
   ///   * Navigation bar: [NavigationBar] (new, replacing [BottomNavigationBar])
   ///   * [Navigation rail](https://m3.material.io/components/navigation-rail): [NavigationRail]
+  ///   * Progress indicators: [CircularProgressIndicator], [LinearProgressIndicator]
   ///   * Radio button: [Radio]
   ///   * Switch: [Switch]
   ///   * Top app bar: [AppBar]