| // Copyright 2016 The Chromium 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/widgets.dart'; |
| |
| class LifecycleWatcher extends StatefulWidget { |
| @override |
| _LifecycleWatcherState createState() => new _LifecycleWatcherState(); |
| } |
| |
| class _LifecycleWatcherState extends State<LifecycleWatcher> |
| with WidgetsBindingObserver { |
| AppLifecycleState _lastLifecyleState; |
| |
| @override |
| void initState() { |
| super.initState(); |
| WidgetsBinding.instance.addObserver(this); |
| } |
| |
| @override |
| void dispose() { |
| WidgetsBinding.instance.removeObserver(this); |
| super.dispose(); |
| } |
| |
| @override |
| void didChangeAppLifecycleState(AppLifecycleState state) { |
| setState(() { |
| _lastLifecyleState = state; |
| }); |
| } |
| |
| @override |
| Widget build(BuildContext context) { |
| if (_lastLifecyleState == null) |
| return const Text('This widget has not observed any lifecycle changes.'); |
| return new Text('The most recent lifecycle state this widget observed was: $_lastLifecyleState.'); |
| } |
| } |
| |
| |
| void main() { |
| runApp(new Center( |
| child: new LifecycleWatcher() |
| )); |
| } |