Flutter音频处理插件native_audio的使用

Flutter音频处理插件native_audio的使用

插件介绍

native_audio 是一个用于Flutter的音频插件，它利用原生Android和iOS的音频播放器来处理音频播放、通知和外部控制（如蓝牙）。

安装与设置

该插件适用于Android和iOS平台。以下是安装和设置步骤：

Android

1. 先决条件：

   • Flutter项目需要最小版本 MinSDK 21
   • Flutter项目需要支持 AndroidX

2. 应用配置： 在Application类中添加以下代码：

   import io.flutter.app.FlutterApplication
   import io.flutter.plugin.common.PluginRegistry
   import io.flutter.plugins.GeneratedPluginRegistrant
   import com.danielgauci.native_audio.NativeAudioPlugin
   
   class Application : FlutterApplication(), PluginRegistry.PluginRegistrantCallback {
   
       override fun onCreate() {
           super.onCreate()
           NativeAudioPlugin.setPluginRegistrantCallback(this)
       }
   
       override fun registerWith(registry: PluginRegistry) {
           GeneratedPluginRegistrant.registerWith(registry)
       }
   }
   

   确保在AndroidManifest.xml文件中反映此更改：

   <application
       android:name=".Application"
       ...
   

   注意：如果不调用NativeAudioPlugin.setPluginRegistrant，当播放音频时会抛出异常。

iOS

1. 先决条件：

   • Flutter项目需要最小版本 iOS 10
   • Flutter项目需要最小构建版本 Swift 4.2

2. 无需额外设置： 对于iOS，不需要进行额外设置。

自定义

1. 通知图标： 可以通过添加名为native_audio_notification_icon的drawable资源来覆盖通知图标。这可以在.xml或其他任何支持的格式中实现。

   注意：仅对Android有用，在iOS上，将始终使用启动图标。

2. 设置跳过时间： 设置跳过时间可以控制向前/向后跳转的时间，当调用skipForward()、skipBackward()或通知中的媒体图标时。

   _audio.setSkipTime(forwardTime: Duration(seconds: 30), backwardTime: Duration(seconds: 10));
   

示例代码

import 'package:flutter/material.dart';

import 'package:native_audio/native_audio.dart';

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

class MyApp extends StatefulWidget {
  [@override](/user/override)
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  var _audio = NativeAudio();
  var _progressText = "0:00:00";
  var _isLoaded = false;
  var _isPlaying = false;
  var _status = "stopped";

  [@override](/user/override)
  void initState() {
    super.initState();

    _audio.setSkipTime(
        forwardTime: Duration(seconds: 30),
        backwardTime: Duration(seconds: 10));
    _listenForAudioEvents();
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Native Audio'),
        ),
        body: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: <Widget>[
            Text(_progressText, textAlign: TextAlign.center),
            Padding(
              padding: EdgeInsets.all(16.0),
              child: Text(_status, textAlign: TextAlign.center),
            ),
            SizedBox(height: 48),
            if (!_isLoaded)
              MaterialButton(
                  child: Text("Play"), onPressed: () => _playSampleAudio()),
            if (_isLoaded)
              MaterialButton(
                  child: Text("Stop"), onPressed: () => _audio.stop()),
            if (!_isPlaying && _isLoaded)
              MaterialButton(
                  child: Text("Resume"), onPressed: () => _audio.resume()),
            if (_isPlaying)
              MaterialButton(
                  child: Text("Pause"), onPressed: () => _audio.pause()),
            if (_isLoaded)
              MaterialButton(
                  child: Text("Seek to 30m"),
                  onPressed: () => _audio.seekTo(Duration(minutes: 30))),
            if (_isLoaded)
              MaterialButton(
                  child: Text("Seek to 70m"),
                  onPressed: () => _audio.seekTo(Duration(minutes: 70))),
            if (_isLoaded)
              MaterialButton(
                  child: Text("Skip Forward"),
                  onPressed: () => _audio.skipForward()),
            if (_isLoaded)
              MaterialButton(
                  child: Text("Skip Backward"),
                  onPressed: () => _audio.skipBackward()),
          ],
        ),
      ),
    );
  }

  void _listenForAudioEvents() {
    _audio.onLoaded = (totalDuration, startedAutomatically) {
      setState(() {
        _isLoaded = true;
        _isPlaying = startedAutomatically;
        _status = "loaded";
      });
    };

    _audio.onResumed = () {
      setState(() => _isPlaying = true);
      _status = "resumed";
    };

    _audio.onPaused = () {
      setState(() {
        _isPlaying = false;
        _status = "paused";
      });
    };

    _audio.onStopped = () {
      setState(() {
        _isLoaded = false;
        _isPlaying = false;
        _status = "stopped";
      });
    };

    _audio.onCompleted = () {
      setState(() {
        _isLoaded = false;
        _isPlaying = false;
        _status = "completed";
      });
    };

    _audio.onProgressChanged = (progress) {
      setState(() {
        this._progressText = _durationToString(progress);
      });
    };
  }

  void _playSampleAudio() {
    setState(() => _status = "loadinging");
    _audio.play(
        "https://s3.amazonaws.com/scifri-episodes/scifri20181123-episode.mp3",
        title: "How The Fashion Industry Is Responding To Climate Change",
        album: "Science Friday",
        artist: "WNYC Studio",
        imageUrl:
            "https://www.sciencefriday.com/wp-content/uploads/2019/09/clothes-close-min.jpg");
  }

  String _durationToString(Duration duration) {
    String twoDigits(int n) {
      if (n >= 10) return "$n";
      return "0$n";
    }

    String twoDigitMinutes = twoDigits(duration.inMinutes.remainder(60));
    String twoDigitSeconds = twoDigits(duration.inSeconds.remainder(60));
    return "${twoDigits(duration.inHours)}:$twoDigitMinutes:$twoDigitSeconds";
  }
}