Dismissible Swipe view for two actions

dismissible_swipe_both_ways.dart

import 'package:flutter/material.dart';

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

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

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 itemsList = List<String>.generate(10, (n) => "List item ${n}");

  ListView generateItemsList() {
    return ListView.builder(
      itemCount: itemsList.length,
      itemBuilder: (context, index) {
        return Dismissible(
          key: Key(itemsList[index]),
          child: InkWell(
              onTap: () {
                print("${itemsList[index]} clicked");
              },
              child: ListTile(title: Text('${itemsList[index]}'))),
          background: slideRightBackground(),
          secondaryBackground: slideLeftBackground(),
          confirmDismiss: (direction) async {
            if (direction == DismissDirection.endToStart) {
              final bool res = await showDialog(
                  context: context,
                  builder: (BuildContext context) {
                    return AlertDialog(
                      content: Text(
                          "Are you sure you want to delete ${itemsList[index]}?"),
                      actions: <Widget>[
                        FlatButton(
                          child: Text(
                            "Cancel",
                            style: TextStyle(color: Colors.black),
                          ),
                          onPressed: () {
                            Navigator.of(context).pop();
                          },
                        ),
                        FlatButton(
                          child: Text(
                            "Delete",
                            style: TextStyle(color: Colors.red),
                          ),
                          onPressed: () {
                            // TODO: Delete the item from DB etc..
                            setState(() {
                              itemsList.removeAt(index);
                            });
                            Navigator.of(context).pop();
                          },
                        ),
                      ],
                    );
                  });
              return res;
            } else {
              // TODO: Navigate to edit page;
            }
          },
        );
      },
    );
  }

  Widget slideRightBackground() {
    return Container(
      color: Colors.green,
      child: Align(
        child: Row(
          mainAxisAlignment: MainAxisAlignment.start,
          children: <Widget>[
            SizedBox(
              width: 20,
            ),
            Icon(
              Icons.edit,
              color: Colors.white,
            ),
            Text(
              " Edit",
              style: TextStyle(
                color: Colors.white,
                fontWeight: FontWeight.w700,
              ),
              textAlign: TextAlign.left,
            ),
          ],
        ),
        alignment: Alignment.centerLeft,
      ),
    );
  }

  Widget slideLeftBackground() {
    return Container(
      color: Colors.red,
      child: Align(
        child: Row(
          mainAxisAlignment: MainAxisAlignment.end,
          children: <Widget>[
            Icon(
              Icons.delete,
              color: Colors.white,
            ),
            Text(
              " Delete",
              style: TextStyle(
                color: Colors.white,
                fontWeight: FontWeight.w700,
              ),
              textAlign: TextAlign.right,
            ),
            SizedBox(
              width: 20,
            ),
          ],
        ),
        alignment: Alignment.centerRight,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: generateItemsList(),
    );
  }
}

Actually the issue is resolved, I was usind an old version of flutter and at that time this property was not present. Once I updated the issue is resolved.