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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';
class PlatformChannel extends StatefulWidget {
const PlatformChannel({Key? key}) : super(key: key);
@override
State<PlatformChannel> createState() => _PlatformChannelState();
}
class _PlatformChannelState extends State<PlatformChannel> {
static const MethodChannel methodChannel =
MethodChannel('samples.flutter.io/battery');
static const EventChannel eventChannel =
EventChannel('samples.flutter.io/charging');
String _batteryLevel = 'Battery level: unknown.';
String _chargingStatus = 'Battery status: unknown.';
Future<void> _getBatteryLevel() async {
String batteryLevel;
try {
final int? result = await methodChannel.invokeMethod('getBatteryLevel');
batteryLevel = 'Battery level: $result%.';
} on PlatformException {
batteryLevel = 'Failed to get battery level.';
}
setState(() {
_batteryLevel = batteryLevel;
});
}
@override
void initState() {
super.initState();
eventChannel.receiveBroadcastStream().listen(_onEvent, onError: _onError);
}
void _onEvent(Object? event) {
setState(() {
_chargingStatus =
"Battery status: ${event == 'charging' ? '' : 'dis'}charging.";
});
}
void _onError(Object error) {
setState(() {
_chargingStatus = 'Battery status: unknown.';
});
}
@override
Widget build(BuildContext context) {
return Material(
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(_batteryLevel, key: const Key('Battery level label')),
Padding(
padding: const EdgeInsets.all(16.0),
child: ElevatedButton(
onPressed: _getBatteryLevel,
child: const Text('Refresh'),
),
),
],
),
Text(_chargingStatus),
],
),
);
}
}
void main() {
runApp(const MaterialApp(home: PlatformChannel()));
}