所以我遵循了“https://flutter.dev/docs/development/platform-integration/platform-channels?tab=android-channel-java-tab”中的所有内容，但是当我单击设备中的浮动按钮时，会显示此错误.
[ERROR:flutter/lib/ui/ui_dart_state.cc(166)] Unhandled Exception: MissingPluginException(No implementation found for method getBatteryLevel on channel battery)
E/flutter ( 4580): #0 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:159:7)
E/flutter ( 4580): <asynchronous suspension>
E/flutter ( 4580): #1 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:334:12)
E/flutter ( 4580): #2 _batteryState._getBatteryLevel (package:flutter_app/main.dart:45:37)
E/flutter ( 4580): #3 _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:992:19)
E/flutter ( 4580): #4 _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:1098:38)
E/flutter ( 4580): #5 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:184:24)
E/flutter ( 4580): #6 TapGestureRecognizer.handleTapUp (package:flutter/src/gestures/tap.dart:524:11)
E/flutter ( 4580): #7 BaseTapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:284:5)
E/flutter ( 4580): #8 BaseTapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:219:7)
E/flutter ( 4580): #9 PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:477:9)
E/flutter ( 4580): #10 PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:78:12)
E/flutter ( 4580): #11 PointerRouter._dispatchEventToRoutes.<anonymous closure> (package:flutter/src/gestures/pointer_router.dart:124:9)
E/flutter ( 4580): #12 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:377:8)
E/flutter ( 4580): #13 PointerRouter._dispatchEventToRoutes (package:flutter/src/gestures/pointer_router.dart:122:18)
E/flutter ( 4580): #14 PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:108:7)
E/flutter ( 4580): #15 GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:220:19)
E/flutter ( 4580): #16 GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:200:22)
E/flutter ( 4580): #17 GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:158:7)
E/flutter ( 4580): #18 GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:104:7)
E/flutter ( 4580): #19 GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:88:7)
E/flutter ( 4580): #20 _rootRunUnary (dart:async/zone.dart:1206:13)
E/flutter ( 4580): #21 _CustomZone.runUnary (dart:async/zone.dart:1100:19)
E/flutter ( 4580): #22 _CustomZone.runUnaryGuarded (dart:async/zone.dart:1005:7)
E/flutter ( 4580): #23 _invoke1 (dart:ui/hooks.dart:267:10)
E/flutter ( 4580): #24 _dispatchPointerDataPacket (dart:ui/hooks.dart:176:5)
E/flutter ( 4580):
主要飞镖： -
import 'dart:ffi';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
void main(){
runApp(
MaterialApp(
home: battery()
)
);
}
class battery extends StatefulWidget {
@override
_batteryState createState() => _batteryState();
}
class _batteryState extends State<battery> {
static const platform = const MethodChannel('battery');
String _batteryLevel = 'error';
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('BatteryDetails'),
),
body: Center(
child: Column(
children: <Widget>[
FloatingActionButton.extended(onPressed: _getBatteryLevel, label: Text('Get battery info')),
Text(_batteryLevel),
],
)
)
);
}
Future<void> _getBatteryLevel() async{
String BatteryLevel;
try {
final int result = await platform.invokeMethod('getBatteryLevel');
BatteryLevel = 'battery Level is $result %.';
}on PlatformException catch (e){
BatteryLevel = "failed to get battery level: '&{e.message}'";
}
setState(() {
_batteryLevel = BatteryLevel;
});
}
}
MainActivity.java:-
package com.example.flutter_app;
import androidx.annotation.NonNull;
import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.FlutterEngine;
import io.flutter.plugin.common.MethodChannel;
import android.content.ContextWrapper;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.BatteryManager;
import android.os.Build.VERSION;
import android.os.Build.VERSION_CODES;
import android.os.Bundle;
public class MainActivity extends FlutterActivity {
private static final String CHANNEL = "battery";
@Override
public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
super.configureFlutterEngine(flutterEngine);
new MethodChannel(flutterEngine.getDartExecutor().getBinaryMessenger(), CHANNEL)
.setMethodCallHandler(
(call, result) -> {
// Note: this method is invoked on the main thread.
if (call.method.equals("getBatteryLevel")) {
int batteryLevel = getBatteryLevel();
if (batteryLevel != -1) {
result.success(batteryLevel);
} else {
result.error("UNAVAILABLE", "Battery level not available.", null);
}
} else {
result.notImplemented();
}
}
);
}
private int getBatteryLevel() {
int batteryLevel = -1;
if (VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {
BatteryManager batteryManager = (BatteryManager) getSystemService(BATTERY_SERVICE);
batteryLevel = batteryManager.getIntProperty(BatteryManager.BATTERY_PROPERTY_CAPACITY);
} else {
Intent intent = new ContextWrapper(getApplicationContext()).
registerReceiver(null, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
batteryLevel = (intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1) * 100) /
intent.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
}
return batteryLevel;
}
}
我是新来的，你能帮我吗也有人能解释一下我发生了什么
public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
super.configureFlutterEngine(flutterEngine);
new MethodChannel(flutterEngine.getDartExecutor().getBinaryMessenger(), CHANNEL)
.setMethodCallHandler(
(call, result)
这部分代码。谢谢你。