Migrated `Checkbox` to Material 3 Colors (#110537)

dev/tools/gen_defaults/bin/gen_defaults.dart

@@ -20,6 +20,7 @@ import 'dart:io';
 import 'package:gen_defaults/app_bar_template.dart';
 import 'package:gen_defaults/button_template.dart';
 import 'package:gen_defaults/card_template.dart';
+import 'package:gen_defaults/checkbox_template.dart';
 import 'package:gen_defaults/chip_action_template.dart';
 import 'package:gen_defaults/chip_filter_template.dart';
 import 'package:gen_defaults/chip_input_template.dart';
@@ -108,6 +109,7 @@ Future<void> main(List<String> args) async {
   ButtonTemplate('md.comp.outlined-button', 'OutlinedButton', '$materialLib/outlined_button.dart', tokens).updateFile();
   ButtonTemplate('md.comp.text-button', 'TextButton', '$materialLib/text_button.dart', tokens).updateFile();
   CardTemplate('Card', '$materialLib/card.dart', tokens).updateFile();
+  CheckboxTemplate('Checkbox', '$materialLib/checkbox.dart', tokens).updateFile();
   ChipActionTemplate('ActionChip', '$materialLib/chip_action.dart', tokens).updateFile();
   ChipFilterTemplate('FilterChip', '$materialLib/chip_filter.dart', tokens).updateFile();
   ChipFilterTemplate('FilterChip', '$materialLib/chip_choice.dart', tokens).updateFile();

dev/tools/gen_defaults/lib/checkbox_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 CheckboxTemplate extends TokenTemplate {
+  const CheckboxTemplate(super.blockName, super.fileName, super.tokens, {
+    super.colorSchemePrefix = '_colors.',
+  });
+
+  @override
+  String generate() => '''
+class _${blockName}DefaultsM3 extends CheckboxThemeData {
+  _${blockName}DefaultsM3(BuildContext context)
+    : _theme = Theme.of(context),
+      _colors = Theme.of(context).colorScheme;
+
+  final ThemeData _theme;
+  final ColorScheme _colors;
+
+  @override
+  MaterialStateProperty<Color> get fillColor {
+    return MaterialStateProperty.resolveWith((Set<MaterialState> states) {
+      if (states.contains(MaterialState.disabled)) {
+        if (states.contains(MaterialState.selected)) {
+          return ${componentColor('md.comp.checkbox.selected.disabled.container')};
+        }
+        return ${componentColor('md.comp.checkbox.unselected.disabled.outline')}.withOpacity(${opacity('md.comp.checkbox.unselected.disabled.container.opacity')});
+      }
+      if (states.contains(MaterialState.selected)) {
+        if (states.contains(MaterialState.pressed)) {
+          return ${componentColor('md.comp.checkbox.selected.pressed.container')};
+        }
+        if (states.contains(MaterialState.hovered)) {
+          return ${componentColor('md.comp.checkbox.selected.hover.container')};
+        }
+        if (states.contains(MaterialState.focused)) {
+          return ${componentColor('md.comp.checkbox.selected.focus.container')};
+        }
+        return ${componentColor('md.comp.checkbox.selected.container')};
+      }
+      if (states.contains(MaterialState.pressed)) {
+        return ${componentColor('md.comp.checkbox.unselected.pressed.outline')};
+      }
+      if (states.contains(MaterialState.hovered)) {
+        return ${componentColor('md.comp.checkbox.unselected.hover.outline')};
+      }
+      if (states.contains(MaterialState.focused)) {
+        return ${componentColor('md.comp.checkbox.unselected.focus.outline')};
+      }
+      return ${componentColor('md.comp.checkbox.unselected.outline')};
+    });
+  }
+
+  @override
+  MaterialStateProperty<Color> get checkColor {
+    return MaterialStateProperty.resolveWith((Set<MaterialState> states) {
+      if (states.contains(MaterialState.disabled)) {
+        if (states.contains(MaterialState.selected)) {
+          return ${componentColor('md.comp.checkbox.selected.disabled.icon')};
+        }
+        return Colors.transparent; // No icons available when the checkbox is unselected.
+      }
+      if (states.contains(MaterialState.selected)) {
+        if (states.contains(MaterialState.pressed)) {
+          return ${componentColor('md.comp.checkbox.selected.pressed.icon')};
+        }
+        if (states.contains(MaterialState.hovered)) {
+          return ${componentColor('md.comp.checkbox.selected.hover.icon')};
+        }
+        if (states.contains(MaterialState.focused)) {
+          return ${componentColor('md.comp.checkbox.selected.focus.icon')};
+        }
+        return ${componentColor('md.comp.checkbox.selected.icon')};
+      }
+      return Colors.transparent; // No icons available when the checkbox is unselected.
+    });
+  }
+
+  @override
+  MaterialStateProperty<Color> get overlayColor {
+    return MaterialStateProperty.resolveWith((Set<MaterialState> states) {
+      if (states.contains(MaterialState.selected)) {
+        if (states.contains(MaterialState.pressed)) {
+          return ${componentColor('md.comp.checkbox.selected.pressed.state-layer')};
+        }
+        if (states.contains(MaterialState.hovered)) {
+          return ${componentColor('md.comp.checkbox.selected.hover.state-layer')};
+        }
+        if (states.contains(MaterialState.focused)) {
+          return ${componentColor('md.comp.checkbox.selected.focus.state-layer')};
+        }
+        return Colors.transparent;
+      }
+      if (states.contains(MaterialState.pressed)) {
+        return ${componentColor('md.comp.checkbox.unselected.pressed.state-layer')};
+      }
+      if (states.contains(MaterialState.hovered)) {
+        return ${componentColor('md.comp.checkbox.unselected.hover.state-layer')};
+      }
+      if (states.contains(MaterialState.focused)) {
+        return ${componentColor('md.comp.checkbox.unselected.focus.state-layer')};
+      }
+      return Colors.transparent;
+    });
+  }
+
+  @override
+  double get splashRadius => ${tokens['md.comp.checkbox.state-layer.size']} / 2;
+
+  @override
+  MaterialTapTargetSize get materialTapTargetSize => _theme.materialTapTargetSize;
+
+  @override
+  VisualDensity get visualDensity => _theme.visualDensity;
+}
+''';
+}