Simplest InheritedWidget Example

main.dart

import 'package:flutter/material.dart';

void main() {
  runApp(CountProvider(
    count: 42,
    child: MyApp(),
  ));
}

class CountProvider extends InheritedWidget {
  final Widget child;
  final int count;

  CountProvider({Key key, this.child, this.count}) : super(key: key, child: child);

  static CountProvider of(BuildContext context) => context.dependOnInheritedWidgetOfExactType(aspect: CountProvider);

  @override
  bool updateShouldNotify(CountProvider oldWidget) => true;
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Center(
      child: RichText(
        text: TextSpan(text: CountProvider.of(context).count.toString()),
        textDirection: TextDirection.ltr,
      ),
    );
  }
}