Flutter stateless UI life cycle - flutter

Question

I have a Flutter app which is based on StatelessWidget. I saw an example with StatefulWidget which allows the programmer to perform some actions in the dispose() method. I am trying to see if the StatelessWidget also provides such feature?
import 'package:flutter/material.dart';
import 'routes.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'My App',
theme: ThemeData(
primarySwatch: colorCustom,
fontFamily: 'Roboto',
),
initialRoute: '/',
routes: routes,
);
}
}
UPDATED
import 'package:flutter/material.dart';
import 'routes.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
Future<bool> _exitApp(BuildContext context) {
return showDialog(
context: context,
child: new AlertDialog(
title: new Text('Do you want to exit this application?'),
content: new Text('We hate to see you leave...'),
actions: <Widget>[
new FlatButton(
onPressed: () => Navigator.of(context).pop(false),
child: new Text('No'),
),
new FlatButton(
onPressed: () => Navigator.of(context).pop(true),
child: new Text('Yes'),
),
],
),
) ??
false;
}
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'My App',
home: WillPopScope(
child: MaterialApp(
theme: ThemeData(
primarySwatch: colorCustom,
fontFamily: 'Roboto',
),
initialRoute: '/',
routes: routes
),
onWillPop: () => _exitApp(context)
)
);
}
Hm, after updating the code, the AlertDialog does not pop up though?

Answer 1

The short answer is no, there is no method similar to dispose() available in a StatelessWidget since as the name suggests, it does not maintain a State.
The long answer is the dispose() mehtod -
The framework calls this method when this State object will never build again. After the framework calls dispose, the State object is considered unmounted and the mounted property is false. It is an error to call setState at this point.
This stage of the lifecycle is terminal: there is no way to remount a State object that has been disposed.
Since the StatelessWidget has no State associated with it, there is no dispose() method.
A similar solution for StatelessWidgets -
So what should we do if we want to run some code only after theStatelessWidgets are popped from the navigation stack or return some data from the StatelessWidget?
Well, this Flutter docmentation page has a this explained along with an example. Hope this helps!