commit 3971ecb39625349ca0430c4439704c6ede455353
author Taha Tesser <tessertaha@gmail.com> Mon Oct 21 20:26:09 2024 +0300
committer dart-internal-monorepo <dart-internal-monorepo@dart-ci-internal.iam.gserviceaccount.com> Mon Oct 21 10:31:05 2024 -0700
tree 1e9e5357fc1864b2a521ca868f37ce52f323d14a
parent 5332b22f8d0aa8ce9a35346a603ada0e679bc338

Fix unattached `MenuController` throws assertion error when calling `MenuController.close()` (#156588)

Fixes [Closing a menu controller that was never attached throws an assertion error](https://github.com/flutter/flutter/issues/156572)

### Code sample

<details>
<summary>expand to view the code sample</summary>

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

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

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key});

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: ElevatedButton(
          onPressed: () => Navigator.of(context).push(
            MaterialPageRoute(
              builder: (context) => const MenuControllerPage(),
            ),
          ),
          child: const Text('Press Me'),
        ),
      ),
    );
  }
}

class MenuControllerPage extends StatefulWidget {
  const MenuControllerPage({super.key});

  @override
  State<MenuControllerPage> createState() => _MenuControllerPageState();
}

class _MenuControllerPageState extends State<MenuControllerPage> {
  // This menu controller is intentionally left as not attached to a MenuAnchor.
  final MenuController _menuController = MenuController();

  @override
  void dispose() {
    // Close the menu when the page is popped.
    _menuController.close();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: ElevatedButton(
          child: const Text('Go back'),
          onPressed: () => Navigator.of(context).pop(),
        ),
      ),
    );
  }
}
```

</details>
https://dart.googlesource.com/external/github.com/flutter/flutter/+/2665a72559501be9f5558b85675d66506ce729d3