tools/dom/templates/html/impl/impl_ScriptProcessorNode.darttemplate

// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

part of $LIBRARY;

$(ANNOTATIONS)class $CLASSNAME$EXTENDS$NATIVESPEC {
  Stream<AudioProcessingEvent> _eventStream;

  /**
   * Get a Stream that fires events when AudioProcessingEvents occur.
   * This particular stream is special in that it only allows one listener to a
   * given stream. Converting the returned Stream [asBroadcast] will likely ruin
   * the soft-real-time properties which which these events are fired and can
   * be processed.
   */
  Stream<AudioProcessingEvent> get onAudioProcess {
    if (_eventStream == null) {
      var controller = new StreamController();
      var callback = (audioData) { 
          if (controller.hasSubscribers) {
            // This stream is a strange combination of broadcast and single
            // subscriber streams. We only allow one listener, but if there is
            // no listener, we don't queue up events, we just drop them on the
            // floor.
            controller.add(audioData);
          }
        };
      _setEventListener(callback);
      _eventStream = controller.stream;
    }
    return _eventStream;
  }

$if DART2JS
    _setEventListener(callback) {
      JS('void', '#.onaudioprocess = #', this,
          convertDartClosureToJS(callback, 1));
    }
$endif

$!MEMBERS
}