flutter_netease_music/lib/pages/home_page.dart

// ignore_for_file: unnecessary_null_comparison

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:audioplayers/audioplayers.dart';

/// Description: home page
/// Time       : 11/06/2023 Monday
/// Author     : liuyuqi.gov@msn.cn
class HomePage extends StatefulWidget {
  HomePage({super.key});

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  String url = "";
  late PlayerMode mode;

  late AudioPlayer _audioPlayer;

  late Duration _duration;
  late Duration _position;
  late StreamSubscription _durationSubscription;
  late StreamSubscription _positionSubscription;
  late StreamSubscription _playerCompleteSubscription;
  late StreamSubscription _playerErrorSubscription;
  late StreamSubscription _playerStateSubscription;

  get _durationText => _duration.toString().split('.').first;
  get _positionText => _position.toString().split('.').first;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Netease Music'),
      ),
      body: Column(
        children: [
          Text(
            _position != null
                ? '${_positionText ?? ''} / ${_durationText ?? ''}'
                : _duration != null
                    ? _durationText
                    : '',
          ),
          Padding(
            padding: const EdgeInsets.all(12.0),
            child: Stack(
              children: [
                Slider(
                  onChanged: (v) {
                    final Position = v * _duration.inMilliseconds;
                    _audioPlayer.seek(Duration(milliseconds: Position.round()));
                  },
                  value: (_position.inMilliseconds > 0 &&
                          _position.inMilliseconds < _duration.inMilliseconds)
                      ? _position.inMilliseconds / _duration.inMilliseconds
                      : 0.0,
                ),
              ],
            ),
          ),
          Row(
            children: [
              IconButton(
                  icon: const Icon(Icons.play_arrow),
                  onPressed: () {
                    _play();
                  }),
              IconButton(
                  icon: const Icon(Icons.pause),
                  onPressed: () {
                    _pause();
                  }),
              IconButton(
                  icon: const Icon(Icons.stop),
                  onPressed: () {
                    _stop();
                  }),
            ],
          )
        ],
      ),
    );
  }

  @override
  void initState() {
    super.initState();
    url = 'http://music.163.com/song/media/outer/url?id=476592630.mp3';
    _initAudioPlayer();
  }

  @override
  void dispose() {
    super.dispose();
    _audioPlayer.dispose();
    _durationSubscription.cancel();
    _positionSubscription.cancel();
    _playerCompleteSubscription.cancel();
    _playerErrorSubscription.cancel();
    _playerStateSubscription.cancel();
  }

  _initAudioPlayer() {
    mode = PlayerMode.mediaPlayer;
    //初始化
    _audioPlayer = AudioPlayer(mode: mode);

    _durationSubscription = _audioPlayer.onDurationChanged.listen((duration) {
      setState(() => _duration = duration);

      if (Theme.of(context).platform == TargetPlatform.iOS) {
        _audioPlayer.startHeadlessService();

        _audioPlayer.setNotification(
            title: 'App Name',
            artist: 'Artist or blank',
            albumTitle: 'Name or blank',
            imageUrl: 'url or blank',
            forwardSkipInterval: const Duration(seconds: 30), // default is 30s
            backwardSkipInterval: const Duration(seconds: 30), // default is 30s
            duration: duration,
            elapsedTime: const Duration(seconds: 0));
      }
    });

    //监听进度
    _positionSubscription =
        _audioPlayer.onAudioPositionChanged.listen((p) => setState(() {
              _position = p;
            }));

    //播放完成
    _playerCompleteSubscription =
        _audioPlayer.onPlayerCompletion.listen((event) {
//          _onComplete();
      setState(() {
        _position = const Duration();
      });
    });

    //监听报错
    _playerErrorSubscription = _audioPlayer.onPlayerError.listen((msg) {
      print('audioPlayer error : $msg');
      setState(() {
//        _playerState = PlayerState.stopped;
        _duration = const Duration(seconds: 0);
        _position = const Duration(seconds: 0);
      });
    });

    //播放状态改变
    _audioPlayer.onPlayerStateChanged.listen((state) {
      if (!mounted) return;
      setState(() {});
    });

    ///// iOS中来自通知区域的玩家状态变化流。
    _audioPlayer.onDurationChanged.listen((state) {
      if (!mounted) return;
    });

//    _playingRouteState = PlayingRouteState.speakers;
  }

  //开始播放
  void _play() async {
    final playPosition = (_position.inMilliseconds > 0 &&
            _position.inMilliseconds < _duration.inMilliseconds)
        ? _position
        : null;
    await _audioPlayer.play(UrlSource(url), position: playPosition);
    _audioPlayer.setPlaybackRate(1.0);
  }

  //暂停
  void _pause() async {
    await _audioPlayer.pause();
  }

  //停止播放
  _stop() async {
    await _audioPlayer.stop();
  }
}