60 lines
1.6 KiB
Dart
60 lines
1.6 KiB
Dart
// Copyright 2014 The Flutter Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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import 'package:flutter/material.dart';
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/// Flutter code sample for [ScaffoldMessenger.of].
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void main() => runApp(const OfExampleApp());
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class OfExampleApp extends StatefulWidget {
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const OfExampleApp({super.key});
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@override
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State<OfExampleApp> createState() => _OfExampleAppState();
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}
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class _OfExampleAppState extends State<OfExampleApp> {
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final GlobalKey<ScaffoldMessengerState> _scaffoldMessengerKey =
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GlobalKey<ScaffoldMessengerState>();
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int _counter = 0;
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void _incrementCounter() {
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setState(() {
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_counter++;
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});
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if (_counter % 10 == 0) {
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_scaffoldMessengerKey.currentState!.showSnackBar(
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const SnackBar(content: Text('A multiple of ten!')),
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);
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}
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}
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@override
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Widget build(BuildContext context) {
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return MaterialApp(
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scaffoldMessengerKey: _scaffoldMessengerKey,
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home: Scaffold(
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appBar: AppBar(title: const Text('ScaffoldMessenger Demo')),
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body: Center(
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child: Column(
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mainAxisAlignment: MainAxisAlignment.center,
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children: <Widget>[
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const Text('You have pushed the button this many times:'),
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Text(
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'$_counter',
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style: Theme.of(context).textTheme.headlineMedium,
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),
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],
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),
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),
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floatingActionButton: FloatingActionButton(
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onPressed: _incrementCounter,
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tooltip: 'Increment',
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child: const Icon(Icons.add),
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),
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),
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);
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}
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}
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