【flutter】Flutter和原生交互提示: MissingPluginExceptio

Z时代
2024-01-10
分类：技术分享

问题描述

flutter获取电池信息的小demo
Performing hot reload...
Syncing files to device OPPO R11...
Reloaded 0 of 419 libraries in 401ms.
E/flutter ( 2440): [ERROR:flutter/shell/common/shell.cc(184)] Dart Error: Unhandled exception:
E/flutter ( 2440): MissingPluginException(No implementation found for method getBatteryLevel on channel samples.flutter.io/battery)
E/flutter ( 2440): #0 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:291:7)

**我跑了一下官方的实例代码,是可以正确获取到电池信息的，但是官方在代码里用的是 new MethodCallHandler()
我在自己的项目里用new MethodCallHandler() 就不行得这样子才可以 newMethodChannel.MethodCallHandler()**

dart文件

问题出现的环境背景及自己尝试过哪些方法

1.是根据文档写的，

相关代码

// 请把代码文本粘贴到下方（请勿用图片代替代码）

package com.example.batterylevel;
import android.os.Bundle;
import io.flutter.app.FlutterActivity;
import io.flutter.plugin.common.MethodCall;
import io.flutter.plugin.common.MethodChannel;
import io.flutter.plugins.GeneratedPluginRegistrant;
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 = "com.example.batterylevel/battery";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
GeneratedPluginRegistrant.registerWith(this);
new MethodChannel(getFlutterView(),CHANNEL).setMethodCallHandler(
new MethodChannel.MethodCallHandler() {
@Override
public void onMethodCall(MethodCall call, MethodChannel.Result result) {
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();
}
}
}
);}

  static const platfrom = const MethodChannel("com.example.batterylevel/battery");
String _batteryLevel ="电量未知";
Future<Null> _getBatteryLevel() async{
String batteryLevel;
try{
final int result = await platfrom.invokeMethod('getBatteryLevel');
batteryLevel = "$result %";
} on PlatformException catch(e){
batteryLevel="电量获取失败:$e.message";
}
setState(() {
_batteryLevel =_batteryLevel;
});}