When swiping away ListTiles, it overlaps on top of surrounding content

listTileOverflow.dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'ListTile test'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  final leftItems = List<String>.generate(3, (i) => "Item ${i + 1}");
  final rightItems = List<String>.generate(3, (i) => "Item ${i + 1}");

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      body: Container(
        child: Row(
          children: [
            Expanded(
              child: ListView.builder(
                itemCount: leftItems.length,
                itemBuilder: (context, index) {
                  final item = leftItems[index];
                  return Dismissible(
                    key: Key('$item left'),
                    onDismissed: (direction) {
                      setState(() {
                        leftItems.removeAt(index);
                      });
                      Scaffold.of(context)
                          .showSnackBar(SnackBar(content: Text("$item dismissed")));
                    },
                    background: Container(color: Colors.red),
                    child: ListTile(title: Text('$item')),
                  );
                },
              ),
            ),
            Expanded(
              child: ListView.builder(
                itemCount: rightItems.length,
                itemBuilder: (context, index) {
                  final item = rightItems[index];
                  return Dismissible(
                    key: Key('$item right'),
                    onDismissed: (direction) {
                      setState(() {
                        rightItems.removeAt(index);
                      });
                      Scaffold.of(context)
                          .showSnackBar(SnackBar(content: Text("$item dismissed")));
                    },
                    background: Container(color: Colors.red),
                    child: ListTile(title: Text('$item')),
                  );
                },
              ),
            ),
          ],
        ),
      ),
    );
  }
}