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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.
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
void main() {
runApp(FlutterView());
}
class FlutterView extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter View',
theme: ThemeData(
primarySwatch: Colors.grey,
),
home: MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
static const String _channel = 'increment';
static const String _pong = 'pong';
static const String _emptyMessage = '';
static const BasicMessageChannel<String> platform =
BasicMessageChannel<String>(_channel, StringCodec());
int _counter = 0;
@override
void initState() {
super.initState();
platform.setMessageHandler(_handlePlatformIncrement);
}
Future<String> _handlePlatformIncrement(String message) async {
setState(() {
_counter++;
});
return _emptyMessage;
}
void _sendFlutterIncrement() {
platform.send(_pong);
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Expanded(
child: Center(
child: Text(
'Platform button tapped $_counter time${ _counter == 1 ? '' : 's' }.',
style: const TextStyle(fontSize: 17.0)),
),
),
Container(
padding: const EdgeInsets.only(bottom: 15.0, left: 5.0),
child: Row(
children: <Widget>[
Image.asset('assets/flutter-mark-square-64.png', scale: 1.5),
const Text('Flutter', style: TextStyle(fontSize: 30.0)),
],
),
),
],
),
floatingActionButton: FloatingActionButton(
onPressed: _sendFlutterIncrement,
child: const Icon(Icons.add),
),
);
}
}