startPlayer()

• Dart API: startPlayer().

You can use startPlayer to play a sound.

• startPlayer() has three optional parameters, depending on your sound source :

  • fromUri: (if you want to play a file or a remote URI)

  • fromDataBuffer: (if you want to play from a data buffer)

  • sampleRate is mandatory if codec == Codec.pcm16. Not used for other codecs.

You must specify one or the three parameters : fromUri, fromDataBuffer, fromStream.

• You use the optional parametercodec: for specifying the audio and file format of the file. Please refer to the Codec compatibility Table to know which codecs are currently supported.

• whenFinished:() : A lambda function for specifying what to do when the playback will be finished.

Very often, the codec: parameter is not useful. Flutter Sound will adapt itself depending on the real format of the file provided. But this parameter is necessary when Flutter Sound must do format conversion (for example to play opusOGG on iOS).

startPlayer() returns a Duration Future, which is the record duration.

Hint: path_provider can be useful if you want to get access to some directories on your device.

Example:

Dart

Javascript

        Directory tempDir = await getTemporaryDirectory();
        File fin = await File ('${tempDir.path}/flutter_sound-tmp.aac');
        Duration d = await myPlayer.startPlayer(fin.path, codec: Codec.aacADTS);

        _playerSubscription = myPlayer.onProgress.listen((e)
        {
                // ...
        });

        Lorem ipsum ...

</div>

Example:

Dart

Javascript

    final fileUri = "https://file-examples.com/wp-content/uploads/2017/11/file_example_MP3_700KB.mp3";

    Duration d = await myPlayer.startPlayer
    (
                fromURI: fileUri,
                codec: Codec.mp3,
                whenFinished: ()
                {
                         print( 'I hope you enjoyed listening to this song' );
                },
    );

        Lorem ipsum ...

</div>

setAudioFocus()

• Dart API: setAudioFocus.

focus: parameter possible values are

• AudioFocus.requestFocus (request focus, but do not do anything special with others App)

• AudioFocus.requestFocusAndStopOthers (your app will have exclusive use of the output audio)

• AudioFocus.requestFocusAndDuckOthers (if another App like Spotify use the output audio, its volume will be lowered)

• AudioFocus.requestFocusAndKeepOthers (your App will play sound above others App)

• AudioFocus.requestFocusAndInterruptSpokenAudioAndMixWithOthers

• AudioFocus.requestFocusTransient (for Android)

• AudioFocus.requestFocusTransientExclusive (for Android)

• AudioFocus.abandonFocus (Your App will not have anymore the audio focus)

Other parameters :

Please look to openAudioSession() to understand the meaning of the other parameters

Example:

Dart

Javascript

        myPlayer.setAudioFocus(focus: AudioFocus.requestFocusAndDuckOthers);

        Lorem ipsum ...

</div>

seekToPlayer()

• Dart API: seekToPlayer().

To seek to a new location. The player must already be playing or paused. If not, an exception is thrown.

Example:

Dart

Javascript

await myPlayer.seekToPlayer(Duration(milliseconds: milliSecs));

        Lorem ipsum ...

</div>

nowPlaying()

• Dart API: nowPlaying().

This verb is used to set the Lock screen fields without starting a new playback. The fields 'dataBuffer' and 'trackPath' of the Track parameter are not used. Please refer to 'startPlayerFromTrack' for the meaning of the others parameters. Remark setUIProgressBar() is implemented only on iOS.

Example:

Dart

Javascript

    Track track = Track( codec: Codec.opusOGG, trackPath: fileUri, trackAuthor: '3 Inches of Blood', trackTitle: 'Axes of Evil', albumArtAsset: albumArt );
    await nowPlaying(Track);

        Lorem ipsum ...

</div>

resumePlayer()

• Dart API: resumePlayer().

Use this verbe to resume the current playback. An exception is thrown if the player is not in the "paused" state.

Example:

Dart

Javascript

await myPlayer.resumePlayer();

        Lorem ipsum ...

</div>

foodSink

• Dart API: foodSink.

The sink side of the Food Controller that you use when you want to play asynchronously live data. This StreamSink accept two kinds of objects :

• FoodData (the buffers that you want to play)

• FoodEvent (a call back to be called after a resynchronisation)

Example:

This example shows how to play Live data, without Back Pressure from Flutter Sound

Dart

Javascript

await myPlayer.startPlayerFromStream(codec: Codec.pcm16, numChannels: 1, sampleRate: 48000);

myPlayer.foodSink.add(FoodData(aBuffer));
myPlayer.foodSink.add(FoodData(anotherBuffer));
myPlayer.foodSink.add(FoodData(myOtherBuffer));
myPlayer.foodSink.add(FoodEvent((){_mPlayer.stopPlayer();}));

        Lorem ipsum ...

</div>

playerState, isPlaying, isPaused, isStopped. getPlayerState()

• Dart API: .

• Dart API: .

• Dart API: .

• Dart API: .

• Dart API: .

This four verbs is used when the app wants to get the current Audio State of the player.

playerState is an attribut which can have the following values :

• isStopped /// Player is stopped

• isPlaying /// Player is playing

• isPaused /// Player is paused

• isPlaying is a boolean attribut which is true when the player is in the "Playing" mode.

• isPaused is a boolean atrribut which is true when the player is in the "Paused" mode.

• isStopped is a boolean atrribut which is true when the player is in the "Stopped" mode.

Flutter Sound shows in the playerState attribut the last known state. When the Audio State of the background OS engine changes, the playerState parameter is not updated exactly at the same time. If you want the exact background OS engine state you must use PlayerState theState = await myPlayer.getPlayerState(). Acutually getPlayerState() is only implemented on iOS.

Example:

        swtich(myPlayer.playerState)
        {
                case PlayerState.isPlaying: doSomething; break;
                case PlayerState.isStopped: doSomething; break;
                case PlayerState.isPaused: doSomething; break;
        }
        ...
        if (myPlayer.isStopped) doSomething;
        if (myPlayer.isPlaying) doSomething;
        if (myPlayer.isPaused) doSomething;
        ...
        PlayerState theState = await myPlayer.getPlayerState();
        ...

        Lorem ipsum ...

</div>

startPlayerFromTrack()

• Dart API: .

Use this verb to play data from a track specification and display controls on the lock screen or an Apple Watch. The Audio Session must have been open with the parameter withUI.

• track parameter is a simple structure which describe the sound to play. Please see

• whenFinished:() : A function for specifying what to do when the playback will be finished.

• onPaused:() : this parameter can be :

  • a call back function to call when the user hit the Skip Pause button on the lock screen

  • null : The pause button will be handled by Flutter Sound internal

• onSkipForward:() : this parameter can be :

  • a call back function to call when the user hit the Skip Forward button on the lock screen

  • null : The Skip Forward button will be disabled

• onSkipBackward:() : this parameter can be :

  • a call back function to call when the user hit the Skip Backward button on the lock screen

  • : The Skip Backward button will be disabled

• removeUIWhenStopped : is a boolean to specify if the UI on the lock screen must be removed when the sound is finished or when the App does a stopPlayer(). Most of the time this parameter must be true. It is used only for the rare cases where the App wants to control the lock screen between two playbacks. Be aware that if the UI is not removed, the button Pause/Resume, Skip Backward and Skip Forward remain active between two playbacks. If you want to disable those button, use the API verb nowPlaying(). Remark: actually this parameter is implemented only on iOS.

• defaultPauseResume : is a boolean value to specify if Flutter Sound must pause/resume the playback by itself when the user hit the pause/resume button. Set this parameter to FALSE if the App wants to manage itself the pause/resume button. If you do not specify this parameter and the onPaused parameter is specified then Flutter Sound will assume FALSE. If you do not specify this parameter and the onPaused parameter is not specified then Flutter Sound will assume TRUE. Remark: actually this parameter is implemented only on iOS.

startPlayerFromTrack() returns a Duration Future, which is the record duration.

Example:

    final fileUri = "https://file-examples.com/wp-content/uploads/2017/11/file_example_MP3_700KB.mp3";
    Track track = Track( codec: Codec.opusOGG, trackPath: fileUri, trackAuthor: '3 Inches of Blood', trackTitle: 'Axes of Evil', albumArtAsset: albumArt )
    Duration d = await myPlayer.startPlayerFromTrack
    (
                track,
                whenFinished: ()
                {
                         print( 'I hope you enjoyed listening to this song' );
                },
    );

        Lorem ipsum ...

</div>

Creating the Player instance.

• Dart API: constructor.

This is the first thing to do, if you want to deal with playbacks. The instanciation of a new player does not do many thing. You are safe if you put this instanciation inside a global or instance variable initialization.

Example:

Dart

Javascript

        FlutterSoundPlayer myPlayer = FlutterSoundPlayer();

        Lorem ipsum ...

</div>

setUIProgressBar()

• Dart API: setUIProgressBar().

This verb is used if the App wants to control itself the Progress Bar on the lock screen. By default, this progress bar is handled automaticaly by Flutter Sound. Remark setUIProgressBar() is implemented only on iOS.

Example:

Dart

Javascript

        Duration progress = (await getProgress())['progress'];
        Duration duration = (await getProgress())['duration'];
        setUIProgressBar(progress: Duration(milliseconds: progress.milliseconds - 500), duration: duration)

        Lorem ipsum ...

</div>

pausePlayer()

• Dart API: pausePlayer().

Use this verbe to pause the current playback. An exception is thrown if the player is not in the "playing" state.

Example:

Dart

Javascript

await myPlayer.pausePlayer();

        Lorem ipsum ...

</div>

isDecoderSupported()

• Dart API: .

This verb is useful to know if a particular codec is supported on the current platform. Returns a Future.

Example:

         if ( await myPlayer.isDecoderSupported(Codec.opusOGG) ) doSomething;

        Lorem ipsum ...

</div>

setVolume()

• Dart API: setVolume().

The parameter is a floating point number between 0 and 1. Volume can be changed when player is running. Manage this after player starts.

Example:

Dart

Javascript

await myPlayer.setVolume(0.1);

        Lorem ipsum ...

</div>

Food

• Dart API: food.

• Dart API: foodData.

• Dart API: food.

This are the objects that you can add to foodSink The Food class has two others inherited classes :

• FoodData (the buffers that you want to play)

• FoodEvent (a call back to be called after a resynchronisation)

Example:

This example shows how to play Live data, without Back Pressure from Flutter Sound

Dart

Javascript

await myPlayer.startPlayerFromStream(codec: Codec.pcm16, numChannels: 1, sampleRate: 48000);

myPlayer.foodSink.add(FoodData(aBuffer));
myPlayer.foodSink.add(FoodData(anotherBuffer));
myPlayer.foodSink.add(FoodData(myOtherBuffer));
myPlayer.foodSink.add(FoodEvent(()async {await _mPlayer.stopPlayer(); setState((){});}));

        Lorem ipsum ...

</div>

getProgress()

• Dart API: .

This verb is used to get the current progress of a playback. It returns a Map with two Duration entries : 'progress' and 'duration'. Remark : actually only implemented on iOS.

Example:

        Duration progress = (await getProgress())['progress'];
        Duration duration = (await getProgress())['duration'];

        Lorem ipsum ...

</div>

setSubscriptionDuration()

• Dart API: setSubscriptionDuration().

This verb is used to change the default interval between two post on the "Update Progress" stream. (The default interval is 0 (zero) which means "NO post")

Example:

Dart

Javascript

        myPlayer.setSubscriptionDuration(Duration(milliseconds: 100));

        Lorem ipsum ...

</div>

openAudioSession() and closeAudioSession()

• Dart API: openAudioSession.

• Dart API: closeAudioSession.

A player must be opened before used. A player correspond to an Audio Session. With other words, you must open the Audio Session before using it. When you have finished with a Player, you must close it. With other words, you must close your Audio Session. Opening a player takes resources inside the OS. Those resources are freed with the verb closeAudioSession(). It is safe to call this procedure at any time.

• If the Player is not open, this verb will do nothing

• If the Player is currently in play or pause mode, it will be stopped before.

focus: parameter

focus is an optional parameter can be specified during the opening : the Audio Focus. This parameter can have the following values :

• AudioFocus.requestFocusAndStopOthers (your app will have exclusive use of the output audio)

• AudioFocus.requestFocusAndDuckOthers (if another App like Spotify use the output audio, its volume will be lowered)

• AudioFocus.requestFocusAndKeepOthers (your App will play sound above others App)

• AudioFocus.requestFocusAndInterruptSpokenAudioAndMixWithOthers (for Android)

• AudioFocus.requestFocusTransient (for Android)

• AudioFocus.requestFocusTransientExclusive (for Android)

• AudioFocus.doNotRequestFocus (useful if you want to mangage yourself the Audio Focus with the verb setAudioFocus())

The Audio Focus is abandoned when you close your player. If your App must play several sounds, you will probably open your player just once, and close it when you have finished with the last sound. If you close and reopen an Audio Session for each sound, you will probably get unpleasant things for the ears with the Audio Focus.

category

category is an optional parameter used only on iOS. This parameter can have the following values :

• ambient

• multiRoute

• playAndRecord

• playback

• record

• soloAmbient

• audioProcessing

See iOS documentation to understand the meaning of this parameter.

mode

mode is an optional parameter used only on iOS. This parameter can have the following values :

• modeDefault

• modeGameChat

• modeMeasurement

• modeMoviePlayback

• modeSpokenAudio

• modeVideoChat

• modeVideoRecording

• modeVoiceChat

• modeVoicePrompt

See iOS documentation to understand the meaning of this parameter.

audioFlags

are a set of optional flags (used on iOS):

• outputToSpeaker

• allowHeadset

• allowEarPiece

• allowBlueTooth

• allowAirPlay

• allowBlueToothA2DP

device

is the output device (used on Android)

• speaker

• headset,

• earPiece,

• blueTooth,

• blueToothA2DP,

• airPlay

withUI

is a boolean that you set to true if you want to control your App from the lock-screen (using startPlayerFromTrack() during your Audio Session).

You MUST ensure that the player has been closed when your widget is detached from the UI. Overload your widget's dispose() method to closeAudioSession the player when your widget is disposed. In this way you will reset the player and clean up the device resources, but the player will be no longer usable.

@override
void dispose()
{
        if (myPlayer != null)
        {
            myPlayer.closeAudioSession();
            myPlayer = null;
        }
        super.dispose();
}

You may not open many Audio Sessions without closing them. You will be very bad if you try something like :

    while (aCondition)  // *DON'T DO THAT*
    {
            flutterSound = FlutterSoundPlayer().openAudioSession(); // A **new** Flutter Sound instance is created and opened
            flutterSound.startPlayer(bipSound);
    }

openAudioSession() and closeAudioSession() return Futures. You may not use your Player before the end of the initialization. So probably you will await the result of openAudioSession(). This result is the Player itself, so that you can collapse instanciation and initialization together with myPlayer = await FlutterSoundPlayer().openAudioSession();

Example:

Dart

Javascript

    myPlayer = await FlutterSoundPlayer().openAudioSession(focus: Focus.requestFocusAndDuckOthers, outputToSpeaker | allowBlueTooth);

    ...
    (do something with myPlayer)
    ...

    await myPlayer.closeAudioSession();
    myPlayer = null;
    FlutterSoundPlayer myPlayer = FlutterSoundPlayer();

        Lorem ipsum ...

</div>

onProgress

• Dart API: onProgress.

The stream side of the Food Controller : this is a stream on which FlutterSound will post the player progression. You may listen to this Stream to have feedback on the current playback.

PlaybackDisposition has two fields :

• Duration duration (the total playback duration)

• Duration position (the current playback position)

Example:

Dart

Javascript

        _playerSubscription = myPlayer.onProgress.listen((e)
        {
                Duration maxDuration = e.duration;
                Duration position = e.position;
                ...
        }

        Lorem ipsum ...

</div>

stopPlayer()

• Dart API: stopPlayer().

Use this verb to stop a playback. This verb never throw any exception. It is safe to call it everywhere, for example when the App is not sure of the current Audio State and want to recover a clean reset state.

Example:

Dart

Javascript

        await myPlayer.stopPlayer();
        if (_playerSubscription != null)
        {
                _playerSubscription.cancel();
                _playerSubscription = null;
        }

        Lorem ipsum ...

</div>

startPlayerFromStream()

• Dart API: startPlayerFromStream().

This functionnality needs, at least, and Android SDK >= 21

• The only codec supported is actually Codec.pcm16.

• The only value possible for numChannels is actually 1.

• SampleRate is the sample rate of the data you want to play.

Please look to the following notice

Example You can look to the three provided examples :

• This example shows how to play Live data, with Back Pressure from Flutter Sound

• This example shows how to play Live data, without Back Pressure from Flutter Sound

• This example shows how to play some real time sound effects.

Example 1:

Dart

Javascript

await myPlayer.startPlayerFromStream(codec: Codec.pcm16, numChannels: 1, sampleRate: 48000);

await myPlayer.feedFromStream(aBuffer);
await myPlayer.feedFromStream(anotherBuffer);
await myPlayer.feedFromStream(myOtherBuffer);

await myPlayer.stopPlayer();
    );

        Lorem ipsum ...

</div>

Example 2:

Dart

Javascript

await myPlayer.startPlayerFromStream(codec: Codec.pcm16, numChannels: 1, sampleRate: 48000);

myPlayer.foodSink.add(FoodData(aBuffer));
myPlayer.foodSink.add(FoodData(anotherBuffer));
myPlayer.foodSink.add(FoodData(myOtherBuffer));

myPlayer.foodSink.add(FoodEvent((){_mPlayer.stopPlayer();}));

        Lorem ipsum ...

</div>

feedFromStream()

• Dart API: feedFromStream().

This is the verb that you use when you want to play live PCM data synchronously. This procedure returns a Future. It is very important that you wait that this Future is completed before trying to play another buffer.

Example:

• This example shows how to play Live data, with Back Pressure from Flutter Sound

• This example shows how to play some real time sound effects synchronously.

Dart

Javascript

await myPlayer.startPlayerFromStream(codec: Codec.pcm16, numChannels: 1, sampleRate: 48000);

await myPlayer.feedFromStream(aBuffer);
await myPlayer.feedFromStream(anotherBuffer);
await myPlayer.feedFromStream(myOtherBuffer);

await myPlayer.stopPlayer();

        Lorem ipsum ...

</div>