flutter audio_manager ios 播放下一首歌曲时播放器延迟

Question

screen capture of my ios device showing the issue

我正在使用以下库 audio_manager，因为它很新，适用于 ios 和 android，并且实际上具有通知处理功能。在 android 上它使用 android 媒体播放器，在 ios 上它使用 AVplayer。

如果您在此处添加给定示例并更改包含 1 首本地歌曲和 1 首网络歌曲的歌曲列表，仅包含网络歌曲并在真实 ios 设备上进行测试我有一个问题，我实际上无法修复。

首先，这是我在演示项目中替换的列表：

final list = [
    {
      "title": "Ambia",
      "desc": "Taeo Kol",
      "url": "https://www.basicmethods.org/mp3/BM_traxx_25.mp3",
      "coverUrl": "https://www.countrymusicnews.de/images/stories/cd/RodneyAtkins-CaughtUpInTheCountryLP.jpg"
    },
    {
      "title": "Terror",
      "desc": "Taeo Kol",
      "url": "https://dreaddymck.com/Public/MUSIC/FEATURING/project%2081.mp3",
      "coverUrl": "https://images.rapgenius.com/ed068b8684cbf71e619ed940d37b0b80.900x892x1.jpg"
    },
    {
      "title": "Confusing",
      "desc": "Ministri",
      "url": "https://ia800305.us.archive.org/30/items/return_201605/return.mp3",
      "coverUrl": "https://static.vibe.com/uploads/2015/01/MCM9.jpg"
    },
    {
      "title": "Dromeda",
      "desc": "Ministri",
      "url": "https://files.freemusicarchive.org/storage-freemusicarchive-org/music/Creative_Commons/Dead_Combo/CC_Affiliates_Mixtape_1/Dead_Combo_-_01_-_Povo_Que_Cas_Descalo.mp3",
      "coverUrl": "https://static.vibe.com/uploads/2015/01/MCM7-600x600.jpg"
    }
  ];

示例如下：

import 'package:flutter/material.dart';
import 'dart:async';
import 'dart:io';

import 'package:flutter/services.dart';
import 'package:audio_manager/audio_manager.dart';
import 'package:path_provider/path_provider.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _platformVersion = 'Unknown';
  bool isPlaying = false;
  Duration _duration;
  Duration _position;
  double _slider;
  double _sliderVolume;
  String _error;
  num curIndex = 0;
  PlayMode playMode = AudioManager.instance.playMode;

  final list = [
    {
      "title": "Assets",
      "desc": "local assets playback",
      "url": "assets/audio.mp3",
      "coverUrl": "assets/ic_launcher.png"
    },
    {
      "title": "network",
      "desc": "network resouce playback",
      "url": "https://dl.espressif.com/dl/audio/ff-16b-2c-44100hz.m4a",
      "coverUrl": "https://homepages.cae.wisc.edu/~ece533/images/airplane.png"
    }
  ];

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

    initPlatformState();
    setupAudio();
    // loadFile();
  }

  @override
  void dispose() {
    // 释放所有资源
    AudioManager.instance.stop();
    super.dispose();
  }

  void setupAudio() {
    List<AudioInfo> _list = [];
    list.forEach((item) => _list.add(AudioInfo(item["url"],
        title: item["title"], desc: item["desc"], coverUrl: item["coverUrl"])));

    AudioManager.instance.audioList = _list;
    AudioManager.instance.intercepter = true;
    AudioManager.instance.play(auto: false);

    AudioManager.instance.onEvents((events, args) {
      print("$events, $args");
      switch (events) {
        case AudioManagerEvents.start:
          print("start load data callback");
          _position = AudioManager.instance.position;
          _duration = AudioManager.instance.duration;
          _slider = 0;
          setState(() {});
          break;
        case AudioManagerEvents.ready:
          print("ready to play");
          _error = null;
          _sliderVolume = AudioManager.instance.volume;
          _position = AudioManager.instance.position;
          _duration = AudioManager.instance.duration;
          setState(() {});
          AudioManager.instance.seekTo(Duration(seconds: 10));
          break;
        case AudioManagerEvents.seekComplete:
          _position = AudioManager.instance.position;
          _slider = _position.inMilliseconds / _duration.inMilliseconds;
          setState(() {});
          print("seek event is completed. position is [$args]/ms");
          break;
        case AudioManagerEvents.buffering:
          print("buffering $args");
          break;
        case AudioManagerEvents.playstatus:
          isPlaying = AudioManager.instance.isPlaying;
          setState(() {});
          break;
        case AudioManagerEvents.timeupdate:
          _position = AudioManager.instance.position;
          _slider = _position.inMilliseconds / _duration.inMilliseconds;
          setState(() {});
          AudioManager.instance.updateLrc(args["position"].toString());
          break;
        case AudioManagerEvents.error:
          _error = args;
          setState(() {});
          break;
        case AudioManagerEvents.ended:
          AudioManager.instance.next();
          break;
        case AudioManagerEvents.volumeChange:
          _sliderVolume = AudioManager.instance.volume;
          setState(() {});
          break;
        default:
          break;
      }
    });
  }

  void loadFile() async {
    final appDocDir = await getApplicationDocumentsDirectory();
    // Please make sure the `test.mp3` exists in the document directory
    final file = File("${appDocDir.path}/test.mp3");
    AudioInfo info = AudioInfo("file://${file.path}",
        title: "file",
        desc: "local file",
        coverUrl: "https://homepages.cae.wisc.edu/~ece533/images/baboon.png");

    list.add(info.toJson());
    AudioManager.instance.audioList.add(info);
  }

  Future<void> initPlatformState() async {
    String platformVersion;
    try {
      platformVersion = await AudioManager.instance.platformVersion;
    } on PlatformException {
      platformVersion = 'Failed to get platform version.';
    }
    if (!mounted) return;

    setState(() {
      _platformVersion = platformVersion;
    });
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Plugin audio player'),
        ),
        body: Center(
          child: Column(
            children: <Widget>[
              Text('Running on: $_platformVersion\n'),
              Padding(
                padding: EdgeInsets.symmetric(horizontal: 16),
                child: volumeFrame(),
              ),
              Expanded(
                child: ListView.separated(
                    itemBuilder: (context, index) {
                      return ListTile(
                        title: Text(list[index]["title"],
                            style: TextStyle(fontSize: 18)),
                        subtitle: Text(list[index]["desc"]),
                        onTap: () => AudioManager.instance.play(index: index),
                      );
                    },
                    separatorBuilder: (BuildContext context, int index) =>
                        Divider(),
                    itemCount: list.length),
              ),
              Center(
                  child: Text(_error != null
                      ? _error
                      : "${AudioManager.instance.info.title} lrc text: $_position")),
              bottomPanel()
            ],
          ),
        ),
      ),
    );
  }

  Widget bottomPanel() {
    return Column(children: <Widget>[
      Padding(
        padding: EdgeInsets.symmetric(horizontal: 16),
        child: songProgress(context),
      ),
      Container(
        padding: EdgeInsets.symmetric(vertical: 16),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceAround,
          children: <Widget>[
            IconButton(
                icon: getPlayModeIcon(playMode),
                onPressed: () {
                  playMode = AudioManager.instance.nextMode();
                  setState(() {});
                }),
            IconButton(
                iconSize: 36,
                icon: Icon(
                  Icons.skip_previous,
                  color: Colors.black,
                ),
                onPressed: () => AudioManager.instance.previous()),
            IconButton(
              onPressed: () async {
                bool playing = await AudioManager.instance.playOrPause();
                print("await -- $playing");
              },
              padding: const EdgeInsets.all(0.0),
              icon: Icon(
                isPlaying ? Icons.pause : Icons.play_arrow,
                size: 48.0,
                color: Colors.black,
              ),
            ),
            IconButton(
                iconSize: 36,
                icon: Icon(
                  Icons.skip_next,
                  color: Colors.black,
                ),
                onPressed: () => AudioManager.instance.next()),
            IconButton(
                icon: Icon(
                  Icons.menu,
                  color: Colors.black,
                ),
                onPressed: () {
                  print("click menu");
                }),
          ],
        ),
      ),
    ]);
  }

  Widget getPlayModeIcon(PlayMode playMode) {
    switch (playMode) {
      case PlayMode.sequence:
        return Icon(
          Icons.repeat,
          color: Colors.black,
        );
      case PlayMode.shuffle:
        return Icon(
          Icons.shuffle,
          color: Colors.black,
        );
      case PlayMode.single:
        return Icon(
          Icons.repeat_one,
          color: Colors.black,
        );
    }
    return Container();
  }

  Widget songProgress(BuildContext context) {
    var style = TextStyle(color: Colors.black);
    return Row(
      children: <Widget>[
        Text(
          _formatDuration(_position),
          style: style,
        ),
        Expanded(
          child: Padding(
            padding: EdgeInsets.symmetric(horizontal: 5),
            child: SliderTheme(
                data: SliderTheme.of(context).copyWith(
                  trackHeight: 2,
                  thumbColor: Colors.blueAccent,
                  overlayColor: Colors.blue,
                  thumbShape: RoundSliderThumbShape(
                    disabledThumbRadius: 5,
                    enabledThumbRadius: 5,
                  ),
                  overlayShape: RoundSliderOverlayShape(
                    overlayRadius: 10,
                  ),
                  activeTrackColor: Colors.blueAccent,
                  inactiveTrackColor: Colors.grey,
                ),
                child: Slider(
                  value: _slider ?? 0,
                  onChanged: (value) {
                    setState(() {
                      _slider = value;
                    });
                  },
                  onChangeEnd: (value) {
                    if (_duration != null) {
                      Duration msec = Duration(
                          milliseconds:
                              (_duration.inMilliseconds * value).round());
                      AudioManager.instance.seekTo(msec);
                    }
                  },
                )),
          ),
        ),
        Text(
          _formatDuration(_duration),
          style: style,
        ),
      ],
    );
  }

  String _formatDuration(Duration d) {
    if (d == null) return "--:--";
    int minute = d.inMinutes;
    int second = (d.inSeconds > 60) ? (d.inSeconds % 60) : d.inSeconds;
    String format = ((minute < 10) ? "0$minute" : "$minute") +
        ":" +
        ((second < 10) ? "0$second" : "$second");
    return format;
  }

  Widget volumeFrame() {
    return Row(children: <Widget>[
      IconButton(
          padding: EdgeInsets.all(0),
          icon: Icon(
            Icons.audiotrack,
            color: Colors.black,
          ),
          onPressed: () {
            AudioManager.instance.setVolume(0);
          }),
      Expanded(
          child: Padding(
              padding: EdgeInsets.symmetric(horizontal: 0),
              child: Slider(
                value: _sliderVolume ?? 0,
                onChanged: (value) {
                  setState(() {
                    _sliderVolume = value;
                    AudioManager.instance.setVolume(value, showVolume: true);
                  });
                },
              )))
    ]);
  }
}

如果您开始播放歌曲并切换到媒体播放器所在的锁定屏幕，一切正常，您唯一可能注意到的是，歌曲开始播放需要很长时间。（插件实际上缓冲）如果你在媒体播放器上切换下一首歌曲图标，播放图标停止一毫秒，恢复，然后歌曲仍在播放，大约 3-5 秒，然后最终播放下一首歌曲。

如果你检查调试控制台，歌曲稍后开始缓冲，我认为 swift 代码某处有错误，如果你在 mediaplayer 上按 next 或 previous，它应该直接切换到下一首歌曲，实际上它现在无法播放。

希望有人能帮忙！

Answer 1

由于音频管理器的最新更新，该问题已得到修复。

audio_manager: ^0.5.4

您可以在这里下载：https://pub.dev/packages/audio_manager#-installing-tab-

flutter audio_manager ios 播放下一首歌曲时播放器延迟

flutter audio_manager ios delay in player when playing next song

audio

ios

avplayer

swift

flutter