AudioContext#

class AudioContext extends BaseAudioContext

Annotations: @SupportedBrowser.new(SupportedBrowser.CHROME), @SupportedBrowser.new(SupportedBrowser.FIREFOX), @Native.new("AudioContext,webkitAudioContext")

Inheritance

Object → EventTarget → BaseAudioContext → AudioContext

Constructors#

AudioContext() factory#

factory AudioContext()

Implementation

factory AudioContext() => JS(
  'AudioContext',
  'new (window.AudioContext || window.webkitAudioContext)()',
);

Properties#

baseLatency no setter#

num? get baseLatency

Implementation

num? get baseLatency native;

currentTime no setter inherited#

num? get currentTime

Inherited from BaseAudioContext.

Implementation

num? get currentTime native;

destination no setter inherited#

AudioDestinationNode? get destination

Inherited from BaseAudioContext.

Implementation

AudioDestinationNode? get destination native;

hashCode no setter inherited#

int get hashCode

Inherited from Interceptor.

Implementation

int get hashCode => Primitives.objectHashCode(this);

listener no setter inherited#

AudioListener? get listener

Inherited from BaseAudioContext.

Implementation

AudioListener? get listener native;

on no setter inherited#

Events get on

This is an ease-of-use accessor for event streams which should only be used when an explicit accessor is not available.

Inherited from EventTarget.

Implementation

Events get on => new Events(this);

runtimeType no setter inherited#

Type get runtimeType

Inherited from Interceptor.

Implementation

Type get runtimeType =>
    getRuntimeTypeOfInterceptorNotArray(getInterceptor(this), this);

sampleRate no setter inherited#

num? get sampleRate

Inherited from BaseAudioContext.

Implementation

num? get sampleRate native;

state no setter inherited#

String? get state

Inherited from BaseAudioContext.

Implementation

String? get state native;

Methods#

addEventListener() inherited#

void addEventListener( String type, dynamic Function(Event event)? listener, [ bool? useCapture, ]);

Inherited from EventTarget.

Implementation

void addEventListener(
  String type,
  EventListener? listener, [
  bool? useCapture,
]) {
  &#47;&#47; TODO(leafp): This check is avoid a bug in our dispatch code when
  &#47;&#47; listener is null.  The browser treats this call as a no-op in this
  &#47;&#47; case, so it's fine to short-circuit it, but we should not have to.
  if (listener != null) {
    _addEventListener(type, listener, useCapture);
  }
}

close()#

Future<dynamic> close()

Implementation

Future close() => promiseToFuture(JS("", "#.close()", this));

createAnalyser() inherited#

AnalyserNode createAnalyser()

Inherited from BaseAudioContext.

Implementation

AnalyserNode createAnalyser() native;

createBiquadFilter() inherited#

BiquadFilterNode createBiquadFilter()

Inherited from BaseAudioContext.

Implementation

BiquadFilterNode createBiquadFilter() native;

createBuffer() inherited#

AudioBuffer createBuffer( int numberOfChannels, int numberOfFrames, num sampleRate, );

Inherited from BaseAudioContext.

Implementation

AudioBuffer createBuffer(
  int numberOfChannels,
  int numberOfFrames,
  num sampleRate,
) native;

createBufferSource() inherited#

AudioBufferSourceNode createBufferSource()

Inherited from BaseAudioContext.

Implementation

AudioBufferSourceNode createBufferSource() native;

createChannelMerger() inherited#

ChannelMergerNode createChannelMerger([ int? numberOfInputs])

Inherited from BaseAudioContext.

Implementation

ChannelMergerNode createChannelMerger([int? numberOfInputs]) native;

createChannelSplitter() inherited#

ChannelSplitterNode createChannelSplitter([ int? numberOfOutputs])

Inherited from BaseAudioContext.

Implementation

ChannelSplitterNode createChannelSplitter([int? numberOfOutputs]) native;

createConstantSource() inherited#

ConstantSourceNode createConstantSource()

Inherited from BaseAudioContext.

Implementation

ConstantSourceNode createConstantSource() native;

createConvolver() inherited#

ConvolverNode createConvolver()

Inherited from BaseAudioContext.

Implementation

ConvolverNode createConvolver() native;

createDelay() inherited#

DelayNode createDelay([ num? maxDelayTime])

Inherited from BaseAudioContext.

Implementation

DelayNode createDelay([num? maxDelayTime]) native;

createDynamicsCompressor() inherited#

DynamicsCompressorNode createDynamicsCompressor()

Inherited from BaseAudioContext.

Implementation

DynamicsCompressorNode createDynamicsCompressor() native;

createGain() override#

GainNode createGain()

Implementation

GainNode createGain() {
  if (JS('bool', '#.createGain !== undefined', this)) {
    return JS('GainNode', '#.createGain()', this);
  } else {
    return JS('GainNode', '#.createGainNode()', this);
  }
}

createIirFilter() inherited#

IirFilterNode createIirFilter(List<num> feedForward, List<num> feedBack)

Inherited from BaseAudioContext.

Implementation

@JSName('createIIRFilter')
IirFilterNode createIirFilter(
  List<num> feedForward,
  List<num> feedBack,
) native;

createMediaElementSource() inherited#

MediaElementAudioSourceNode createMediaElementSource( MediaElement mediaElement, );

Inherited from BaseAudioContext.

Implementation

MediaElementAudioSourceNode createMediaElementSource(
  MediaElement mediaElement,
) native;

createMediaStreamDestination() inherited#

MediaStreamAudioDestinationNode createMediaStreamDestination()

Inherited from BaseAudioContext.

Implementation

MediaStreamAudioDestinationNode createMediaStreamDestination() native;

createMediaStreamSource() inherited#

MediaStreamAudioSourceNode createMediaStreamSource(MediaStream mediaStream)

Inherited from BaseAudioContext.

Implementation

MediaStreamAudioSourceNode createMediaStreamSource(
  MediaStream mediaStream,
) native;

createOscillator() inherited#

OscillatorNode createOscillator()

Inherited from BaseAudioContext.

Implementation

OscillatorNode createOscillator() native;

createPanner() inherited#

PannerNode createPanner()

Inherited from BaseAudioContext.

Implementation

PannerNode createPanner() native;

createPeriodicWave() inherited#

PeriodicWave createPeriodicWave( List<num> real, List<num> imag, [ Map<dynamic, dynamic>? options, ]);

Inherited from BaseAudioContext.

Implementation

PeriodicWave createPeriodicWave(
  List<num> real,
  List<num> imag, [
  Map? options,
]) {
  if (options != null) {
    var options_1 = convertDartToNative_Dictionary(options);
    return _createPeriodicWave_1(real, imag, options_1);
  }
  return _createPeriodicWave_2(real, imag);
}

createScriptProcessor() override#

ScriptProcessorNode createScriptProcessor([ int? bufferSize, int? numberOfInputChannels, int? numberOfOutputChannels, ]);

Implementation

ScriptProcessorNode createScriptProcessor([
  int? bufferSize,
  int? numberOfInputChannels,
  int? numberOfOutputChannels,
]) {
  var function = JS(
    '=Object',
    '#.createScriptProcessor || '
        '#.createJavaScriptNode',
    this,
    this,
  );
  if (numberOfOutputChannels != null) {
    return JS(
      'ScriptProcessorNode',
      '#.call(#, #, #, #)',
      function,
      this,
      bufferSize,
      numberOfInputChannels,
      numberOfOutputChannels,
    );
  } else if (numberOfInputChannels != null) {
    return JS(
      'ScriptProcessorNode',
      '#.call(#, #, #)',
      function,
      this,
      bufferSize,
      numberOfInputChannels,
    );
  } else if (bufferSize != null) {
    return JS(
      'ScriptProcessorNode',
      '#.call(#, #)',
      function,
      this,
      bufferSize,
    );
  } else {
    return JS('ScriptProcessorNode', '#.call(#)', function, this);
  }
}

createStereoPanner() inherited#

StereoPannerNode createStereoPanner()

Inherited from BaseAudioContext.

Implementation

StereoPannerNode createStereoPanner() native;

createWaveShaper() inherited#

WaveShaperNode createWaveShaper()

Inherited from BaseAudioContext.

Implementation

WaveShaperNode createWaveShaper() native;

decodeAudioData() override#

Future<AudioBuffer> decodeAudioData( ByteBuffer audioData, [ void Function(AudioBuffer decodedData)? successCallback, void Function(DomException error)? errorCallback, ]);

Implementation

Future<AudioBuffer> decodeAudioData(
  ByteBuffer audioData, [
  DecodeSuccessCallback? successCallback,
  DecodeErrorCallback? errorCallback,
]) {
  &#47;&#47; Both callbacks need to be provided if they're being used.
  assert((successCallback == null) == (errorCallback == null));
  &#47;&#47; `decodeAudioData` can exist either in the older callback syntax or the
  &#47;&#47; newer `Promise`-based syntax that also accepts callbacks. In the former,
  &#47;&#47; we synthesize a `Future` to be consistent.
  &#47;&#47; For more details:
  &#47;&#47; https:&#47;&#47;developer.mozilla.org&#47;en-US&#47;docs&#47;Web&#47;API&#47;BaseAudioContext&#47;decodeAudioData
  &#47;&#47; https:&#47;&#47;www.w3.org&#47;TR&#47;webaudio&#47;#dom-baseaudiocontext-decodeaudiodata
  final completer = Completer<Object>();
  var errorInCallbackIsNull = false;

  void success(AudioBuffer decodedData) {
    completer.complete(decodedData);
    successCallback!.call(decodedData);
  }

  final nullErrorString =
      '[AudioContext.decodeAudioData] completed with a null error.';

  void error(DomException? error) {
    &#47;&#47; Safari has a bug where it may return null for the error callback. In
    &#47;&#47; the case where the Safari version still returns a `Promise` and the
    &#47;&#47; error is not null after the `Promise` is finished, the error callback
    &#47;&#47; is called instead in the `Promise`'s `catch` block. Otherwise, and in
    &#47;&#47; the case where a `Promise` is not returned by the API at all, the
    &#47;&#47; callback never gets called (for backwards compatibility, it can not
    &#47;&#47; accept null). Instead, the `Future` completes with a custom string,
    &#47;&#47; indicating that null was given.
    &#47;&#47; https:&#47;&#47;github.com&#47;mdn&#47;webaudio-examples&#47;issues&#47;5
    if (error != null) {
      &#47;&#47; Note that we `complete` and not `completeError`. This is to make sure
      &#47;&#47; that errors in the `Completer` are not thrown if the call gets back
      &#47;&#47; a `Promise`.
      completer.complete(error);
      errorCallback!.call(error);
    } else {
      completer.complete(nullErrorString);
      errorInCallbackIsNull = true;
    }
  }

  var decodeResult;
  if (successCallback == null) {
    decodeResult = JS(
      "creates:AudioBuffer;",
      "#.decodeAudioData(#)",
      this,
      audioData,
    );
  } else {
    decodeResult = JS(
      "creates:AudioBuffer;",
      "#.decodeAudioData(#, #, #)",
      this,
      audioData,
      convertDartClosureToJS(success, 1),
      convertDartClosureToJS(error, 1),
    );
  }

  if (decodeResult != null) {
    &#47;&#47; Promise-based syntax.
    return promiseToFuture<AudioBuffer>(decodeResult).catchError((error) {
      &#47;&#47; If the error was null in the callback, but no longer is now that the
      &#47;&#47; `Promise` is finished, call the error callback. If it's still null,
      &#47;&#47; throw the error string. This is to handle the aforementioned bug in
      &#47;&#47; Safari.
      if (errorInCallbackIsNull) {
        if (error != null) {
          errorCallback?.call(error);
        } else {
          throw nullErrorString;
        }
      }
      throw error;
    });
  }

  &#47;&#47; Callback-based syntax. We use the above completer to synthesize a
  &#47;&#47; `Future` from the callback values. Since we don't use `completeError`
  &#47;&#47; above, `then` is used to simulate an error.
  return completer.future.then((value) {
    if (value is AudioBuffer) return value;
    throw value;
  });
}

dispatchEvent() inherited#

bool dispatchEvent(Event event)

Inherited from EventTarget.

Implementation

bool dispatchEvent(Event event) native;

getOutputTimestamp()#

Map<dynamic, dynamic> getOutputTimestamp()

Implementation

Map getOutputTimestamp() {
  return convertNativeToDart_Dictionary(_getOutputTimestamp_1())!;
}

noSuchMethod() inherited#

dynamic noSuchMethod(Invocation invocation)

Invoked when a nonexistent method or property is accessed.

A dynamic member invocation can attempt to call a member which doesn't exist on the receiving object. Example:

dynamic object = 1;
object.add(42); // Statically allowed, run-time error

This invalid code will invoke the noSuchMethod method of the integer 1 with an Invocation representing the .add(42) call and arguments (which then throws).

Classes can override noSuchMethod to provide custom behavior for such invalid dynamic invocations.

A class with a non-default noSuchMethod invocation can also omit implementations for members of its interface. Example:

class MockList<T> implements List<T> {
  noSuchMethod(Invocation invocation) {
    log(invocation);
    super.noSuchMethod(invocation); // Will throw.
  }
}
void main() {
  MockList().add(42);
}

This code has no compile-time warnings or errors even though the MockList class has no concrete implementation of any of the List interface methods. Calls to List methods are forwarded to noSuchMethod, so this code will log an invocation similar to Invocation.method(#add, [42]) and then throw.

If a value is returned from noSuchMethod, it becomes the result of the original invocation. If the value is not of a type that can be returned by the original invocation, a type error occurs at the invocation.

The default behavior is to throw a NoSuchMethodError.

Inherited from Interceptor.

Implementation

dynamic noSuchMethod(Invocation invocation) {
  throw NoSuchMethodError.withInvocation(this, invocation);
}

removeEventListener() inherited#

void removeEventListener( String type, dynamic Function(Event event)? listener, [ bool? useCapture, ]);

Inherited from EventTarget.

Implementation

void removeEventListener(
  String type,
  EventListener? listener, [
  bool? useCapture,
]) {
  &#47;&#47; TODO(leafp): This check is avoid a bug in our dispatch code when
  &#47;&#47; listener is null.  The browser treats this call as a no-op in this
  &#47;&#47; case, so it's fine to short-circuit it, but we should not have to.
  if (listener != null) {
    _removeEventListener(type, listener, useCapture);
  }
}

resume() inherited#

Future<dynamic> resume()

Inherited from BaseAudioContext.

Implementation

Future resume() => promiseToFuture(JS("", "#.resume()", this));

suspend()#

Future<dynamic> suspend()

Implementation

Future suspend() => promiseToFuture(JS("", "#.suspend()", this));

toString() inherited#

String toString()

A string representation of this object.

Some classes have a default textual representation, often paired with a static parse function (like int.parse). These classes will provide the textual representation as their string representation.

Other classes have no meaningful textual representation that a program will care about. Such classes will typically override toString to provide useful information when inspecting the object, mainly for debugging or logging.

Inherited from Interceptor.

Implementation

String toString() => Primitives.objectToHumanReadableString(this);

Operators#

operator ==() inherited#

bool operator ==(Object other)

The equality operator.

The default behavior for all Objects is to return true if and only if this object and other are the same object.

Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:

Total: It must return a boolean for all arguments. It should never throw.
Reflexive: For all objects o, o == o must be true.
Symmetric: For all objects o1 and o2, o1 == o2 and o2 == o1 must either both be true, or both be false.
Transitive: For all objects o1, o2, and o3, if o1 == o2 and o2 == o3 are true, then o1 == o3 must be true.

The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.

If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.

Inherited from Interceptor.

Implementation

bool operator ==(Object other) => identical(this, other);

Static Properties#

supported no setter#

bool get supported

Checks if this type is supported on the current platform.

Implementation

static bool get supported =>
    JS('bool', '!!(window.AudioContext || window.webkitAudioContext)');