Flutter Dismissible with Delete text

gistfile1.txt

import 'package:flutter/material.dart';

void main() => runApp(new MaterialApp(
      home: new HomePage('Dismissible Example'),
    ));

class HomePage extends StatelessWidget {
  String title;
  final items = new List<String>.generate(10000, (i) => "Item $i");

  HomePage(this.title);

  @override
  Widget build(BuildContext context) {
    var listView = new ListView.builder(
      itemCount: items.length,
      itemBuilder: (context, index) {
        var item = items[index];
        return new Dismissible(
          direction: DismissDirection.endToStart,
          key: new Key(item),
          onDismissed: (direction) {
            items.removeAt(index);
          },
          background: new Container(
              padding: EdgeInsets.only(right: 20.0),
              color: Colors.red,
              child: new Align(
                alignment: Alignment.centerRight,
                child: new Text('Delete',
                    textAlign: TextAlign.right,
                    style: new TextStyle(color: Colors.white)),
              )),
          child: new ListTile(
            title: new Text('$item'),
          ),
        );
      },
    );
    var scafford = new Scaffold(
      appBar: new AppBar(title: new Text(title)),
      body: listView,
    );
    return scafford;
  }
}

Thanks for the code snippet...
You no need to add Align widget, use alignment property of Container Widget to align center-right instead.

 background: Container(
   padding: EdgeInsets.only(right: 20.0),
   alignment: Alignment.centerRight,
   color: Colors.red,
   child: Text(
     'Delete',
      textAlign: TextAlign.right,
      style: TextStyle(color: Colors.white),
    ),
  ),