在 Flutter 中播放自定义声音

Question

我正在尝试播放我在资产文件夹中放入应用程序文件夹的自定义 mp3 声音，就像您对字体或图像文件所做的那样，但我真的不知道如何继续。我想我可能需要将音频文件注册到 pubspec.yaml 中，但是如何？

我该怎么玩呢？

我已经检查了这两个答案： How to play a custom sound in Flutter?

Flutter - Play custom sounds updated?

但是第一个太老了，第二个使用URL作为声音路径：const kUrl2 = "http://www.rxlabz.com/labz/audio.mp3";，而我喜欢播放的声音是在应用程序中，而不是在线。那么...我该怎么做呢？

这是我当前的代码，如您所见，只有一个浮动按钮。 而且我需要在我在代码中声明的那一点开始声音。

但是visual studio用红色下划线的各个部分： await：表示 await 无法识别。 audioPlugin.play：是说它也无法识别

import 'dart:io';
import 'dart:typed_data';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
void main() => runApp(new MyApp());

Directory tempDir = await getTemporaryDirectory();
File tempFile = new File('${tempDir.path}/demo.mp3');
await tempFile.writeAsBytes(bytes, flush: true);
AudioPlayer audioPlugin = new AudioPlayer();


class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {


  void _incrementCounter() {
    setState(() {
      print("Button Pressed");

      ///
      /// 
      /// 
      /// Here I Need To start Playing the Sound
      /// 
      /// 
      /// 
      /// 
      audioPlugin.play(tempFile.uri.toString(), isLocal: true);

    });
  }



  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new Center(),
      floatingActionButton: new FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: new Icon(Icons.add),
      ),
    );
  }
}

Answer 1

使用音频播放器包 => https://pub.dev/packages/audioplayers

将密钥添加到 iOS 支持的 plist

<key>NSAppTransportSecurity</key>
<dict>
    <key>NSAllowsArbitraryLoads</key>
    <true/>
</dict>

添加依赖到 pubspec.yaml 文件

audioplayers: ^0.13.2

颤振代码：

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

class AudioTest extends StatefulWidget {
  @override
  _AudioTestState createState() => _AudioTestState();
}

class _AudioTestState extends State<AudioTest> {

  static AudioCache _player = AudioCache();
  static const _audioPath = "count_down.mp3";
  AudioPlayer _audioPlayer = AudioPlayer();

  Future<AudioPlayer> playAudio() async {
    return _player.play(_audioPath);
  }

  void _stop(){
    if (_audioPlayer != null) {
      _audioPlayer.stop();
  }

  @override
  void initState() {

    playAudio().then((player) {
      _audioPlayer = player;
    });

    super.initState();
  }

  @override
  Widget build(BuildContext context) {

    return homeScreen();
  }

  Widget homeScreen() {
    return Scaffold();
    //Enter your code here
  }
}

Answer 2

虽然不好看，但是……

将 mp3 文件添加到 assets 文件夹并将其添加到 pubspec.yaml，如 this。

使用rootBundle.load(asset)将资产加载为二进制数据

使用path_provider 获取应用的临时文件夹位置

使用常规dart:io 在tempDir 中打开一个文件（可能使用资产名称）并将bytes 写入其中。

从file:///folderPath/fileName形式的临时文件名形成file URL

将此传递给audioplayer，将isLocal 设置为true（iOS 上需要）。

import 'dart:async';
import 'dart:io';
import 'dart:typed_data';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:audioplayer/audioplayer.dart';
import 'package:path_provider/path_provider.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Audio Player Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key key}) : super(key: key);

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  AudioPlayer audioPlugin = AudioPlayer();
  String mp3Uri;

  @override
  void initState() {
    _load();
  }

  Future<Null> _load() async {
    final ByteData data = await rootBundle.load('assets/demo.mp3');
    Directory tempDir = await getTemporaryDirectory();
    File tempFile = File('${tempDir.path}/demo.mp3');
    await tempFile.writeAsBytes(data.buffer.asUint8List(), flush: true);
    mp3Uri = tempFile.uri.toString();
    print('finished loading, uri=$mp3Uri');
  }

  void _playSound() {
    if (mp3Uri != null) {
      audioPlugin.play(mp3Uri, isLocal: true);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Audio Player Demo Home Page'),
      ),
      body: Center(),
      floatingActionButton: FloatingActionButton(
        onPressed: _playSound,
        tooltip: 'Play',
        child: const Icon(Icons.play_arrow),
      ),
    );
  }
}