NavigationBar only allows labelTextStyle from NavigationBarTheme  #158508

import 'package:flutter/material.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    const TextStyle selectedTextStyle =
        TextStyle(fontSize: 15, color: Color(0xFF00FF00));
    const TextStyle unselectedTextStyle =
        TextStyle(fontSize: 15, color: Color(0xFF0000FF));
    const TextStyle disabledTextStyle =
        TextStyle(fontSize: 16, color: Color(0xFFFF0000));

    return MaterialApp(
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
          navigationBarTheme: NavigationBarThemeData(
        labelTextStyle: WidgetStatePropertyAll(
          TextStyle(
            fontSize: 14,
            fontWeight: FontWeight.bold,
            color: Theme.of(context).colorScheme.primary,
          ),
        ),
      )),
      home: Scaffold(
        appBar: AppBar(
          title: const Text('NavigationBar Sample'),
        ),
        bottomNavigationBar: NavigationBar(
          labelTextStyle: const WidgetStateProperty<TextStyle?>.fromMap(
            <WidgetStatesConstraint, TextStyle?>{
              WidgetState.disabled: disabledTextStyle,
              WidgetState.selected: selectedTextStyle,
              WidgetState.any: unselectedTextStyle,
            },
          ),
          onDestinationSelected: null,
          destinations: const <Widget>[
            NavigationDestination(
              icon: Icon(Icons.home),
              label: 'Home',
            ),
            NavigationDestination(
              icon: Icon(Icons.favorite_rounded),
              label: 'Favorites',
            ),
            NavigationDestination(
              enabled: false,
              icon: Icon(Icons.settings),
              label: 'Settings',
            ),
          ],
        ),
      ),
    );
  }
}