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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Template: dev/snippets/config/templates/stateful_widget_restoration_material.tmpl
//
// Comment lines marked with "▼▼▼" and "▲▲▲" are used for authoring
// of samples, and may be ignored if you are just exploring the sample.
// Flutter code sample for showDatePicker
//
//***************************************************************************
//* ▼▼▼▼▼▼▼▼ description ▼▼▼▼▼▼▼▼ (do not modify or remove section marker)
// This sample demonstrates how to create a restorable Material date picker.
// This is accomplished by enabling state restoration by specifying
// [MaterialApp.restorationScopeId] and using [Navigator.restorablePush] to
// push [DatePickerDialog] when the button is tapped.
//* ▲▲▲▲▲▲▲▲ description ▲▲▲▲▲▲▲▲ (do not modify or remove section marker)
//***************************************************************************
import 'package:flutter/material.dart';
void main() => runApp(const MyApp());
/// This is the main application widget.
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
static const String _title = 'Flutter Code Sample';
@override
Widget build(BuildContext context) {
return const MaterialApp(
restorationScopeId: 'app',
title: _title,
home: MyStatefulWidget(restorationId: 'main'),
);
}
}
/// This is the stateful widget that the main application instantiates.
class MyStatefulWidget extends StatefulWidget {
const MyStatefulWidget({Key? key, this.restorationId}) : super(key: key);
final String? restorationId;
@override
State<MyStatefulWidget> createState() => _MyStatefulWidgetState();
}
/// This is the private State class that goes with MyStatefulWidget.
/// RestorationProperty objects can be used because of RestorationMixin.
class _MyStatefulWidgetState extends State<MyStatefulWidget>
with RestorationMixin {
// In this example, the restoration ID for the mixin is passed in through
// the [StatefulWidget]'s constructor.
@override
String? get restorationId => widget.restorationId;
//********************************************************************
//* ▼▼▼▼▼▼▼▼ code ▼▼▼▼▼▼▼▼ (do not modify or remove section marker)
final RestorableDateTime _selectedDate =
RestorableDateTime(DateTime(2021, 7, 25));
late final RestorableRouteFuture<DateTime?> _restorableDatePickerRouteFuture =
RestorableRouteFuture<DateTime?>(
onComplete: _selectDate,
onPresent: (NavigatorState navigator, Object? arguments) {
return navigator.restorablePush(
_datePickerRoute,
arguments: _selectedDate.value.millisecondsSinceEpoch,
);
},
);
static Route<DateTime> _datePickerRoute(
BuildContext context,
Object? arguments,
) {
return DialogRoute<DateTime>(
context: context,
builder: (BuildContext context) {
return DatePickerDialog(
restorationId: 'date_picker_dialog',
initialEntryMode: DatePickerEntryMode.calendarOnly,
initialDate: DateTime.fromMillisecondsSinceEpoch(arguments! as int),
firstDate: DateTime(2021, 1, 1),
lastDate: DateTime(2022, 1, 1),
);
},
);
}
@override
void restoreState(RestorationBucket? oldBucket, bool initialRestore) {
registerForRestoration(_selectedDate, 'selected_date');
registerForRestoration(
_restorableDatePickerRouteFuture, 'date_picker_route_future');
}
void _selectDate(DateTime? newSelectedDate) {
if (newSelectedDate != null) {
setState(() {
_selectedDate.value = newSelectedDate;
ScaffoldMessenger.of(context).showSnackBar(SnackBar(
content: Text(
'Selected: ${_selectedDate.value.day}/${_selectedDate.value.month}/${_selectedDate.value.year}'),
));
});
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: OutlinedButton(
onPressed: () {
_restorableDatePickerRouteFuture.present();
},
child: const Text('Open Date Picker'),
),
),
);
}
//* ▲▲▲▲▲▲▲▲ code ▲▲▲▲▲▲▲▲ (do not modify or remove section marker)
//********************************************************************
}