The locale-specific GlobalMaterialLocalizations subclass
is called NnMaterialLocalizations,
and the LocalizationsDelegate subclass is
_NnMaterialLocalizationsDelegate.
The value of NnMaterialLocalizations.delegate
is an instance of the delegate, and is all
that’s needed by an app that uses these localizations.

The delegate class includes basic date and number format
localizations. All of the other localizations are defined by String
valued property getters in NnMaterialLocalizations, like this:

These are the English translations, of course.
To complete the job you need to change the return
value of each getter to an appropriate Nynorsk string.

The getters return “raw” Dart strings that have an r prefix,
like r'About $applicationName',
because sometimes the strings contain variables with a $ prefix.
The variables are expanded by parameterized localization methods:

The date patterns and symbols of the locale will also need to
be specified. In the source code, the date patterns and symbols
are defined like this: