theming

Subclass ThemeExtension, register one instance per ThemeData through the extensions list, read it with Theme.of(context).extension<T>(), and write a real lerp so MaterialApp's AnimatedTheme interpolates your tokens during a light/dark switch. Covers colors, radii, shadows, text styles and booleans, the missing-extension crash, the copyWith trap that drops every other extension, and why you need == and hashCode, all verified with widget tests on Flutter 3.44.8.

The 2026 way to set an accent color in Flutter with Material 3: ColorScheme.fromSeed, the colorSchemeSeed shorthand, the seven DynamicSchemeVariant options, dark mode, dynamic_color on Android 12+, and harmonizing brand colors. Tested on Flutter 3.27.1 and Dart 3.11.

End-to-end dark mode in .NET MAUI 11: AppThemeBinding, SetAppThemeColor, RequestedTheme, UserAppTheme override with persistence, the RequestedThemeChanged event, and the per-platform Info.plist and MainActivity bits that the docs gloss over.