出现错误MediaPlayerNative7313：无法创建媒体播放器-Flutter

如何解决出现错误MediaPlayerNative7313：无法创建媒体播放器-Flutter

我正在建立带闹钟的倒计时，我使用audioplayers库作为声音，我尝试在不同时刻播放提示音，所以我尝试了以下代码：

if（timer ==“ 00:50”）player.play（“ bip.wav”）

并且它无法正常工作，当我重新启动应用程序时，声音停止工作，并且出现此错误：

E/MediaPlayerNative( 6964): Unable to create media player
E/AudioplayersPlugin( 6964): Unexpected error!
E/AudioplayersPlugin( 6964): java.lang.RuntimeException: Unable to access resource
E/MediaPlayerNative( 7313): pause called in state 0,mPlayer(0xe8091b60)
E/AudioplayersPlugin( 7313): java.lang.RuntimeException: Unable to access resource
E/AudioplayersPlugin( 7313):    at xyz.luan.audioplayers.WrappedMediaPlayer.setSource(WrappedMediaPlayer.java:423)
E/AudioplayersPlugin( 7313):    at xyz.luan.audioplayers.WrappedMediaPlayer.setUrl(WrappedMediaPlayer.java:61)
E/AudioplayersPlugin( 7313):    at xyz.luan.audioplayers.AudioplayersPlugin.handleMethodCall(AudioplayersPlugin.java:82)
E/AudioplayersPlugin( 7313):    at xyz.luan.audioplayers.AudioplayersPlugin.onMethodCall(AudioplayersPlugin.java:60)
E/AudioplayersPlugin( 7313):    at io.Flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233)
E/AudioplayersPlugin( 7313):    at io.Flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85)
E/AudioplayersPlugin( 7313):    at io.Flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:692)
E/AudioplayersPlugin( 7313):    at android.os.MessageQueue.nativePollOnce(Native Method)
E/AudioplayersPlugin( 7313):    at android.os.MessageQueue.next(MessageQueue.java:326)
E/AudioplayersPlugin( 7313):    at android.os.Looper.loop(Looper.java:160)

这是我的代码：

import 'package:Flutter/cupertino.dart';
import 'package:audioplayers/audio_cache.dart';
import 'package:Flutter/material.dart';

var player = AudioCache();


class Alarm extends StatefulWidget {
  @override
  _AlarmState createState() => _AlarmState();
}

class _AlarmState extends State<Alarm> with TickerProviderStateMixin {
  AnimationController animationController;



  String get timer {
    Duration duration =
        animationController.duration * animationController.value;
    return "${(duration.inMinutes).toString().padLeft(2,'0')}:${(duration.inSeconds % 60).toString().padLeft(2,'0')}";
  }  

@override
  void initState() {
    super.initState();

    animationController =
        AnimationController(
            vsync: this,duration: Duration(minutes: 1)
        );
  }    
  void Countdown() {
    if (animationController.isAnimating) {
      animationController.stop();
    } else {
      animationController.reverse(
          from: animationController.value == 0.0
              ? 1.0
              : animationController.value);
    };
  }
 

@override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,children: [

            Align(
              alignment: FractionalOffset.center,child: Column(
                mainAxisAlignment: MainAxisAlignment.center,crossAxisAlignment: CrossAxisAlignment.center,children: <Widget>[
                  Container(
                    height: 90,),AnimatedBuilder(
                      animation: animationController,builder: (_,Widget child) {
                      **if (timer == "00:50") player.play("bip.wav");**
                        return Text(timer,style: TextStyle(
                              fontWeight: FontWeight.w200,color: Colors.white,fontSize: 100.0,)    
                        );    
                      }
                  ),Container(

                    child: Row(
                      mainAxisAlignment:
                      MainAxisAlignment.center,children: <Widget>[
                        FloatingActionButton(
                          elevation: 0.0,child: AnimatedBuilder(
                              animation: animationController,Widget child) {
                                return Icon(
                                  animationController
                                      .isAnimating
                                      ? Icons.pause
                                      : Icons.play_arrow,size: 50,);
                              }),backgroundColor: Colors.transparent,splashColor: Colors.white,onpressed: () {

                            Countdown();

                            setState(() {
                              Icon(animationController
                                  .isAnimating
                                  ? Icons.pause
                                  : Icons.play_arrow);
                            });
                          },)
                      ],)
                ],],);
  }
}

谢谢！

解决方法

您应该使用

Timer.periodic( ...)

因此您可以每10分钟播放一次声音。