title: Flutter ListView scroll animation overlapping sibling widget
body: <p>Hoping someone can help with this and it's not a bug and it's just me being silly.</p>
  <p>There is very strange behavior from listview when it's not taking the full length of the screen and in a column.</p>
  <p>When you scroll down, the animation at max extent persists and overlaps. I'm assuming this is a bug and not by design.</p>
  <p>Here's the simple code to reproduce.</p>
  <pre><code>import 'package:flutter/material.dart';
  
  void main() {
    runApp(MyApp(
      items: List&lt;MessageItem&gt;.generate(
        33,
        (i) =&gt; MessageItem(&quot;Sender $i&quot;, &quot;Message body $i&quot;),
      ),
    ));
  }
  
  class MyApp extends StatelessWidget {
    final List&lt;MessageItem&gt; items;
  
    MyApp({Key key, @required this.items}) : super(key: key);
  
    @override
    Widget build(BuildContext context) {
      final title = 'Mixed List';
  
      return MaterialApp(
        title: title,
        home: Scaffold(
          appBar: AppBar(
            title: Text(title),
          ),
          body: Column(
            children: [
              Expanded(
                child: Container(),
              ),
              Expanded(
                child: ListView.builder(
                  itemCount: items.length,
                  itemBuilder: (context, index) {
                    final item = items[index];
  
                    return ListTile(
                      title: item.buildTitle(context),
                      subtitle: item.buildSubtitle(context),
                    );
                  },
                ),
              ),
            ],
          ),
        ),
      );
    }
  }
  
  /// A ListItem that contains data to display a message.
  class MessageItem {
    final String sender;
    final String body;
  
    MessageItem(this.sender, this.body);
  
    Widget buildTitle(BuildContext context) =&gt; Text(sender);
  
    Widget buildSubtitle(BuildContext context) =&gt; Text(body);
  }
  </code></pre>
  <p><img src="https://user-images.githubusercontent.com/20642661/94435310-e132fc00-0192-11eb-93ed-9e3c4cad9f2f.gif" alt="bug" /></p>