title: How to invoke a rebuild of a stateless widget?
body: <h2>Context</h2>
  <p>I have two stateless widgets (pages): <code>HomePage</code> and <code>DetailsPage</code>. Obviously the application starts and launches the <code>HomePage</code>. There is a button the user can press to navigate to the <code>DetailsPage</code> with a <code>Navigator.pop()</code> button to navigate back to the <code>HomePage</code>.</p>
  <p>I know when the <code>DetailsPage</code> is done being used  with the <code>.whenComplete()</code> method. It is at this point I want to rebuild the <code>HomePage</code> widget.</p>
  <h2>Code</h2>
  <p>This is the minimum reproduction of my behavior.</p>
  <code>main.dart</code>
  <pre class="lang-dart prettyprint-override"><code>import 'package:example/home.dart';
  import 'package:flutter/material.dart';
  
  void main() =&gt; runApp(MyApp());
  
  class MyApp extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return MaterialApp(home: HomePage());
    }
  }
  </code></pre>
  <code>home.dart</code>
  <pre class="lang-dart prettyprint-override"><code>import 'package:example/details.dart';
  import 'package:flutter/material.dart';
  
  class HomePage extends StatelessWidget {
    static const name = 'Home Page';
    const HomePage() : super();
  
    @override
    Widget build(BuildContext context) {
      return Scaffold(
        body: Center(
          child: MaterialButton(
            color: Colors.blue,
            textColor: Colors.white,
            child: Text(name),
            onPressed: () {
              Navigator.push(
                context,
                MaterialPageRoute(builder: DetailsPage.builder),
              ).whenComplete(() =&gt; print('Rebuild now.'));
            },
          ),
        ),
      );
    }
  }
  </code></pre>
  <code>details.dart</code>
  <pre class="lang-dart prettyprint-override"><code>import 'package:flutter/material.dart';
  
  class DetailsPage extends StatelessWidget {
    static const name = 'Details Page';
    static WidgetBuilder builder = (BuildContext _) =&gt; DetailsPage();
    const DetailsPage();
  
    @override
    Widget build(BuildContext context) {
      return Scaffold(
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Text(name),
              MaterialButton(
                color: Colors.blue,
                textColor: Colors.white,
                child: Text('Go Back'),
                onPressed: () =&gt; Navigator.pop(context),
              ),
            ],
          ),
        ),
      );
    }
  }
  </code></pre>
  <h2>Question</h2>
  <p>How can I invoke a rebuild of this stateless widget (<code>HomePage</code>) at the <code>.whenComplete()</code> method callback?</p>