The "swipe to dismiss" pattern is common in many mobile apps. For example, when writing an email app, you might want to allow a user to swipe away email messages to delete them from a list.

Flutter makes this task easy by providing theDismissible widget. Learn how to implement swipe to dismiss with the following steps:

1. Create a list of items.
2. Wrap each item in aDismissible widget.
3. Provide "leave behind" indicators.

First, create a list of items. For detailed instructions on how to create a list, follow theWorking with long lists recipe.

In this example, you want 20 sample items to work with. To keep it simple, generate a list of strings.

final items =List<String>.generate(20, (i) =>'Item${i + 1}');

Display each item in the list on screen. Users won't be able to swipe these items away just yet.

ListView.builder(  itemCount: items.length,  itemBuilder: (context, index) {    return ListTile(title:Text(items[index]));  },)

In this step, give users the ability to swipe an item off the list by using theDismissible widget.

After the user has swiped away the item, remove the item from the list and display a snackbar. In a real app, you might need to perform more complex logic, such as removing the item from a web service or database.

Update theitemBuilder() function to return aDismissible widget:

itemBuilder: (context, index) {  final item = items[index];  return Dismissible(    // Each Dismissible must contain a Key. Keys allow Flutter to    // uniquely identify widgets.    key:Key(item),    // Provide a function that tells the app    // what to do after an item has been swiped away.    onDismissed: (direction) {      // Remove the item from the data source.      setState(() {        items.removeAt(index);      });      // Then show a snackbar.      ScaffoldMessenger.of(        context,      ).showSnackBar(SnackBar(content:Text('$item dismissed')));    },    child:ListTile(title:Text(item)),  );},

As it stands, the app allows users to swipe items off the list, but it doesn't give a visual indication of what happens when they do. To provide a cue that items are removed, display a "leave behind" indicator as they swipe the item off the screen. In this case, the indicator is a red background.

To add the indicator, provide abackground parameter to theDismissible.

  ScaffoldMessenger.of(context)      .showSnackBar(SnackBar(content:Text('$item dismissed')));},// Show a red background as the item is swiped away.background:Container(color:Colors.red),child:ListTile(  title:Text(item),),

import 'package:flutter/material.dart';void main() {  runApp(const MyApp());}// MyApp is a StatefulWidget. This allows updating the state of the// widget when an item is removed.class MyApp extends StatefulWidget {  const MyApp({super.key});  @override  MyAppState createState() {    return MyAppState();  }}class MyAppState extends State<MyApp> {  final items = List<String>.generate(20, (i) => 'Item ${i + 1}');  @override  Widget build(BuildContext context) {    const title = 'Dismissing Items';    return MaterialApp(      title: title,      theme: ThemeData(        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),      ),      home: Scaffold(        appBar: AppBar(title: const Text(title)),        body: ListView.builder(          itemCount: items.length,          itemBuilder: (context, index) {            final item = items[index];            return Dismissible(              // Each Dismissible must contain a Key. Keys allow Flutter to              // uniquely identify widgets.              key: Key(item),              // Provide a function that tells the app              // what to do after an item has been swiped away.              onDismissed: (direction) {                // Remove the item from the data source.                setState(() {                  items.removeAt(index);                });                // Then show a snackbar.                ScaffoldMessenger.of(                  context,                ).showSnackBar(SnackBar(content: Text('$item dismissed')));              },              // Show a red background as the item is swiped away.              background: Container(color: Colors.red),              child: ListTile(title: Text(item)),            );          },        ),      ),    );  }}