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Use Theme Selector

A syntax sugar for useQuery but limited to detect Platform Brightness only.

Use to adapt property between light and dark mode:

"".n
    ..useThemeSelector(
        context,
        light: (v) => v..color = Colors.black,
        dark: (v) => v..color = Colors.white,
    );

n.Box()
    ..useThemeSelector(
        light: (v) => v..color = Colors.black,
        dark: (v) => v..color = Colors.white,
    );

Best Practice

If you want to get Media Query, then use useQuery instead.