inherited_widget_issue

inherited_widget_issue.dart

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';

void main() {
  runApp(const DemoApp());
}

class DemoApp extends StatefulWidget {
  const DemoApp({Key? key}) : super(key: key);

  @override
  _DemoAppState createState() => _DemoAppState();
}

class _DemoAppState extends State<DemoApp> {
  late ThemeMode themeMode;

  @override
  void initState() {
    themeMode = ThemeMode.light;
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    /// Not working with itemBuilder context.
    return FrogColor(
      child: MaterialApp(
        home: SafeArea(
          child: Scaffold(
            body: ListView.builder(
              itemCount: 1,
              itemBuilder: (context, index) {
                final frogColor = FrogColor.of(context);
                return RadioListTile(
                  activeColor: frogColor,
                  value: index,
                  groupValue: 0,
                  onChanged: (value) {},
                );
              },
            ),
          ),
        ),
      ),
    );

    /// Working with outer context
    // return FrogColor(
    //   child: Builder(
    //     builder: (context) => MaterialApp(
    //       home: SafeArea(
    //         child: Scaffold(
    //           body: ListView.builder(
    //             itemCount: 1,
    //             itemBuilder: (_, index) => RadioListTile(
    //               activeColor: FrogColor.of(context),
    //               value: index,
    //               groupValue: 0,
    //               onChanged: (value) {},
    //             ),
    //           ),
    //         ),
    //       ),
    //     ),
    //   ),
    // );
  }
}

class FrogColor extends StatefulWidget {
  final Widget child;

  const FrogColor({Key? key, required this.child}) : super(key: key);

  static Color of(BuildContext context) {
    final _FrogInherited? result =
        context.dependOnInheritedWidgetOfExactType<_FrogInherited>();
    assert(result != null, 'No FrogColor found in context');
    return result!.color;
  }

  @override
  _FrogColorState createState() => _FrogColorState();
}

class _FrogColorState extends State<FrogColor> with WidgetsBindingObserver {
  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance!.addObserver(this);
  }

  @override
  void didChangePlatformBrightness() {
    super.didChangePlatformBrightness();
    setState(() {});
  }

  @override
  void dispose() {
    WidgetsBinding.instance!.removeObserver(this);
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final resolveColor =
        WidgetsBinding.instance!.window.platformBrightness == Brightness.light
            ? Colors.blueAccent
            : Colors.blueGrey;
    return _FrogInherited(
      child: widget.child,
      state: this,
      color: resolveColor,
    );
  }
}

class _FrogInherited extends InheritedWidget {
  const _FrogInherited({
    Key? key,
    required this.color,
    required Widget child,
    required _FrogColorState state,
  }) : super(key: key, child: child);

  final Color color;

  @override
  bool updateShouldNotify(_FrogInherited old) => color != old.color;
}