mirror of
https://github.com/flutter/flutter.git
synced 2025-06-03 00:51:18 +00:00
5491c8c146
This auto-formats all *.dart files in the repository outside of the `engine` subdirectory and enforces that these files stay formatted with a presubmit check. **Reviewers:** Please carefully review all the commits except for the one titled "formatted". The "formatted" commit was auto-generated by running `dev/tools/format.sh -a -f`. The other commits were hand-crafted to prepare the repo for the formatting change. I recommend reviewing the commits one-by-one via the "Commits" tab and avoiding Github's "Files changed" tab as it will likely slow down your browser because of the size of this PR. --------- Co-authored-by: Kate Lovett <katelovett@google.com> Co-authored-by: LongCatIsLooong <31859944+LongCatIsLooong@users.noreply.github.com>
72 lines
2.3 KiB
Dart
72 lines
2.3 KiB
Dart
// 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.
|
|
|
|
import 'package:flutter/material.dart';
|
|
|
|
/// Flutter code sample for [FutureBuilder].
|
|
|
|
void main() => runApp(const FutureBuilderExampleApp());
|
|
|
|
class FutureBuilderExampleApp extends StatelessWidget {
|
|
const FutureBuilderExampleApp({super.key});
|
|
|
|
@override
|
|
Widget build(BuildContext context) {
|
|
return const MaterialApp(home: FutureBuilderExample());
|
|
}
|
|
}
|
|
|
|
class FutureBuilderExample extends StatefulWidget {
|
|
const FutureBuilderExample({super.key});
|
|
|
|
@override
|
|
State<FutureBuilderExample> createState() => _FutureBuilderExampleState();
|
|
}
|
|
|
|
class _FutureBuilderExampleState extends State<FutureBuilderExample> {
|
|
final Future<String> _calculation = Future<String>.delayed(
|
|
const Duration(seconds: 2),
|
|
() => 'Data Loaded',
|
|
);
|
|
|
|
@override
|
|
Widget build(BuildContext context) {
|
|
return DefaultTextStyle(
|
|
style: Theme.of(context).textTheme.displayMedium!,
|
|
textAlign: TextAlign.center,
|
|
child: FutureBuilder<String>(
|
|
future: _calculation, // a previously-obtained Future<String> or null
|
|
builder: (BuildContext context, AsyncSnapshot<String> snapshot) {
|
|
List<Widget> children;
|
|
if (snapshot.hasData) {
|
|
children = <Widget>[
|
|
const Icon(Icons.check_circle_outline, color: Colors.green, size: 60),
|
|
Padding(
|
|
padding: const EdgeInsets.only(top: 16),
|
|
child: Text('Result: ${snapshot.data}'),
|
|
),
|
|
];
|
|
} else if (snapshot.hasError) {
|
|
children = <Widget>[
|
|
const Icon(Icons.error_outline, color: Colors.red, size: 60),
|
|
Padding(
|
|
padding: const EdgeInsets.only(top: 16),
|
|
child: Text('Error: ${snapshot.error}'),
|
|
),
|
|
];
|
|
} else {
|
|
children = const <Widget>[
|
|
SizedBox(width: 60, height: 60, child: CircularProgressIndicator()),
|
|
Padding(padding: EdgeInsets.only(top: 16), child: Text('Awaiting result...')),
|
|
];
|
|
}
|
|
return Center(
|
|
child: Column(mainAxisAlignment: MainAxisAlignment.center, children: children),
|
|
);
|
|
},
|
|
),
|
|
);
|
|
}
|
|
}
|