Adobe® Flex® 4 Language Reference
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flash.media 
Sound 
Packageflash.media
Classpublic class Sound
InheritanceSound Inheritance EventDispatcher Inheritance Object
Subclasses SoundAsset

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The Sound class lets you work with sound in an application. The Sound class lets you create a Sound object, load and play an external MP3 file into that object, close the sound stream, and access data about the sound, such as information about the number of bytes in the stream and ID3 metadata. More detailed control of the sound is performed through the sound source — the SoundChannel or Microphone object for the sound — and through the properties in the SoundTransform class that control the output of the sound to the computer's speakers.

In Flash Player 10 and later and AIR 1.5 and later, you can also use this class to work with sound that is generated dynamically. In this case, the Sound object uses the function you assign to a sampleData event handler to poll for sound data. The sound is played as it is retrieved from a ByteArray object that you populate with sound data. You can use Sound.extract() to extract sound data from a Sound object, after which you can manipulate it before writing it back to the stream for playback.

To control sounds that are embedded in a SWF file, use the properties in the SoundMixer class.

Note: The ActionScript 3.0 Sound API differs from ActionScript 2.0. In ActionScript 3.0, you cannot take sound objects and arrange them in a hierarchy to control their properties.

When you use this class, consider the following security model:

  • Loading and playing a sound is not allowed if the calling file is in a network sandbox and the sound file to be loaded is local.
  • By default, loading and playing a sound is not allowed if the calling file is local and tries to load and play a remote sound. A user must grant explicit permission to allow this type of access.
  • Certain operations dealing with sound are restricted. The data in a loaded sound cannot be accessed by a file in a different domain unless you implement a cross-domain policy file. Sound-related APIs that fall under this restriction are Sound.id3, SoundMixer.computeSpectrum(), SoundMixer.bufferTime, and the SoundTransform class.

However, in Adobe AIR, content in the application security sandbox (content installed with the AIR application) are not restricted by these security limitations.

For more information related to security, see the following:

  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The Flash Player Developer Center Topic: Security

View the examples

See also



Public Properties
 PropertyDefined By
  bytesLoaded : uint
[read-only] Returns the currently available number of bytes in this sound object.
Sound
  bytesTotal : int
[read-only] Returns the total number of bytes in this sound object.
Sound
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  id3 : ID3Info
[read-only] Provides access to the metadata that is part of an MP3 file.
Sound
  isBuffering : Boolean
[read-only] Returns the buffering state of external MP3 files.
Sound
  length : Number
[read-only] The length of the current sound in milliseconds.
Sound
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
  url : String
[read-only] The URL from which this sound was loaded.
Sound
Public Methods
 MethodDefined By
  
Sound(stream:URLRequest = null, context:SoundLoaderContext = null)
Creates a new Sound object.
Sound
 Inherited
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event.
EventDispatcher
  
Closes the stream, causing any download of data to cease.
Sound
 Inherited
Dispatches an event into the event flow.
EventDispatcher
  
extract(target:ByteArray, length:Number, startPosition:Number = -1):Number
Extracts raw sound data from a Sound object.
Sound
 Inherited
Checks whether the EventDispatcher object has any listeners registered for a specific type of event.
EventDispatcher
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
  
load(stream:URLRequest, context:SoundLoaderContext = null):void
Initiates loading of an external MP3 file from the specified URL.
Sound
  
play(startTime:Number = 0, loops:int = 0, sndTransform:flash.media:SoundTransform = null):SoundChannel
Generates a new SoundChannel object to play back the sound.
Sound
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes a listener from the EventDispatcher object.
EventDispatcher
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
 Inherited
Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.
EventDispatcher
Events
 Event Summary Defined By
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.EventDispatcher
  Dispatched when data has loaded successfully.Sound
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.EventDispatcher
  Dispatched by a Sound object when ID3 data is available for an MP3 sound.Sound
  Dispatched when an input/output error occurs that causes a load operation to fail.Sound
  Dispatched when a load operation starts.Sound
  Dispatched when data is received as a load operation progresses.Sound
  Dispatched when the player requests new audio data.Sound
Property Detail

bytesLoaded

property
bytesLoaded:uint  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Returns the currently available number of bytes in this sound object. This property is usually useful only for externally loaded files.



Implementation
    public function get bytesLoaded():uint

bytesTotal

property 
bytesTotal:int  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Returns the total number of bytes in this sound object.



Implementation
    public function get bytesTotal():int

id3

property 
id3:ID3Info  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Provides access to the metadata that is part of an MP3 file.

MP3 sound files can contain ID3 tags, which provide metadata about the file. If an MP3 sound that you load using the Sound.load() method contains ID3 tags, you can query these properties. Only ID3 tags that use the UTF-8 character set are supported.

Flash Player 9 and later and the AIR runtime support ID3 2.0 tags, specifically 2.3 and 2.4. The following tables list the standard ID3 2.0 tags and the type of content the tags represent. The Sound.id3 property provides access to these tags through the format my_sound.id3.COMM, my_sound.id3.TIME, and so on. The first table describes tags that can be accessed either through the ID3 2.0 property name or the ActionScript property name. The second table describes ID3 tags that are supported but do not have predefined properties in ActionScript.

ID3 2.0 tagCorresponding Sound class property
COMMSound.id3.comment
TALBSound.id3.album
TCONSound.id3.genre
TIT2Sound.id3.songName
TPE1Sound.id3.artist
TRCKSound.id3.track
TYERSound.id3.year

The following table describes ID3 tags that are supported but do not have predefined properties in the Sound class. You access them by calling mySound.id3.TFLT, mySound.id3.TIME, and so on.

PropertyDescription
TFLTFile type
TIMETime
TIT1Content group description
TIT2Title/song name/content description
TIT3Subtitle/description refinement
TKEYInitial key
TLANLanguages
TLENLength
TMEDMedia type
TOALOriginal album/movie/show title
TOFNOriginal filename
TOLYOriginal lyricists/text writers
TOPEOriginal artists/performers
TORYOriginal release year
TOWNFile owner/licensee
TPE1Lead performers/soloists
TPE2Band/orchestra/accompaniment
TPE3Conductor/performer refinement
TPE4Interpreted, remixed, or otherwise modified by
TPOSPart of a set
TPUBPublisher
TRCKTrack number/position in set
TRDARecording dates
TRSNInternet radio station name
TRSOInternet radio station owner
TSIZSize
TSRCISRC (international standard recording code)
TSSESoftware/hardware and settings used for encoding
TYERYear
WXXXURL link frame

When using this property, consider the Flash Player security model:

  • The id3 property of a Sound object is always permitted for SWF files that are in the same security sandbox as the sound file. For files in other sandboxes, there are security checks.
  • When you load the sound, using the load() method of the Sound class, you can specify a context parameter, which is a SoundLoaderContext object. If you set the checkPolicyFile property of the SoundLoaderContext object to true, Flash Player checks for a URL policy file on the server from which the sound is loaded. If a policy file exists and permits access from the domain of the loading SWF file, then the file is allowed to access the id3 property of the Sound object; otherwise it is not.

However, in Adobe AIR, content in the application security sandbox (content installed with the AIR application) are not restricted by these security limitations.

For more information related to security, see the following:

  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The Flash Player Developer Center Topic: Security



Implementation
    public function get id3():ID3Info

See also


Example  ( How to use this example )
The following example reads the ID3 information from a sound file and displays it in a text field.

In the constructor, the sound file is loaded but it is not set to play. Here, it is assumed that the file is in the SWF directory. The system must have permission in order to read the ID3 tags of a loaded sound file. If there is ID3 information in the file and the program is permitted to read it, an Event.ID3 event will be fired and the id3 property of the sound file will be populated. The id3 property contains an ID3Info object with all of the ID3 information.

In the id3Handler() method, the file's ID3 tags are stored in id3, an ID3Info class object. A text field is instantiated to display the list of the ID3 tags. The for loop iterates through all the ID3 2.0 tags and appends the name and value to the content of the text field. Using ID3 info (ID3Info) properties, the artist, song name, and album are also appended. ActionScript 3.0 and Flash Player 9 and later support ID3 2.0 tags, specifically 2.3 and 2.4. If you iterate through properties like in the for loop, only ID3 2.0 tags will appear. However, the data from the earlier versions are also stored in the song's id3 property and can be accessed using ID3 info class properties. The tags for the ID3 1.0 are at the end of the file while the ID3 2.0 tags are in the beginning of the file. (Sometimes, the files may have both earlier and later version tags in the same place.) If a file encoded with both version 1.0 and 2.0 tags at the beginning and the end of the file, the method id3Handler() will be invoked twice. It first reads the 2.0 version and then the version 1.0. If only ID3 1.0 tag is available, then the information is accessible via the ID3 info properties, like id3.songname. For ID3 2.0, id3.TITS property will retrieve the song name using the new tag (TITS).

Note that no error handling is written for this example and if the ID3 content is long, the result may go beyond the viewable area.

package {
    import flash.display.Sprite;
    import flash.media.Sound;
    import flash.net.URLRequest;
    import flash.media.ID3Info;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.events.Event;

    public class Sound_id3Example extends Sprite {
        private var snd:Sound = new Sound();       
        private var myTextField:TextField = new TextField();

        public function Sound_id3Example() {
            snd.addEventListener(Event.ID3, id3Handler);
            snd.load(new URLRequest("mySound.mp3"));
        }
    
        private function id3Handler(event:Event):void {
            var id3:ID3Info = snd.id3;

            myTextField.autoSize = TextFieldAutoSize.LEFT;
            myTextField.border = true;

            myTextField.appendText("Received ID3 Info: \n");
              
            for (var propName:String in id3) {
                myTextField.appendText(propName + " = " + id3[propName] + "\n");
            }
 
            myTextField.appendText("\n" + "Artist: " + id3.artist + "\n");
            myTextField.appendText("Song name: " + id3.songName + "\n");
            myTextField.appendText("Album: " + id3.album + "\n\n"); 
 
            this.addChild(myTextField);
        }
    }
}

isBuffering

property 
isBuffering:Boolean  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Returns the buffering state of external MP3 files. If the value is true, any playback is currently suspended while the object waits for more data.



Implementation
    public function get isBuffering():Boolean

length

property 
length:Number  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The length of the current sound in milliseconds.



Implementation
    public function get length():Number

url

property 
url:String  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The URL from which this sound was loaded. This property is applicable only to Sound objects that were loaded using the Sound.load() method. For Sound objects that are associated with a sound asset from a SWF file's library, the value of the url property is null.

When you first call Sound.load(), the url property initially has a value of null, because the final URL is not yet known. The url property will have a non-null value as soon as an open event is dispatched from the Sound object.

The url property contains the final, absolute URL from which a sound was loaded. The value of url is usually the same as the value passed to the stream parameter of Sound.load(). However, if you passed a relative URL to Sound.load() the value of the url property represents the absolute URL. Additionally, if the original URL request is redirected by an HTTP server, the value of the url property reflects the final URL from which the sound file was actually downloaded. This reporting of an absolute, final URL is equivalent to the behavior of LoaderInfo.url.



Implementation
    public function get url():String

See also

Constructor Detail

Sound

()Constructor
public function Sound(stream:URLRequest = null, context:SoundLoaderContext = null)

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Creates a new Sound object. If you pass a valid URLRequest object to the Sound constructor, the constructor automatically calls the load() function for the Sound object. If you do not pass a valid URLRequest object to the Sound constructor, you must call the load() function for the Sound object yourself, or the stream will not load.

Once load() is called on a Sound object, you can't later load a different sound file into that Sound object. To load a different sound file, create a new Sound object.

In Flash Player 10 and later and AIR 1.5 and later, instead of using load(), you can use the sampleData event handler to load sound dynamically into the Sound object.

Parameters
stream:URLRequest (default = null) — The URL that points to an external MP3 file.
 
context:SoundLoaderContext (default = null) — An optional SoundLoader context object, which can define the buffer time (the minimum number of milliseconds of MP3 data to hold in the Sound object's buffer) and can specify whether the application should check for a cross-domain policy file prior to loading the sound.
Method Detail

close

()method
public function close():void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Closes the stream, causing any download of data to cease. No data may be read from the stream after the close() method is called.


Throws
IOError — The stream could not be closed, or the stream was not open.

Example  ( How to use this example )

In the following example, when the user clicks on the Stop button, the Sound.close() method will be called and the sound will stop streaming.

In the constructor, a text field is created for the Start and Stop button. When the user clicks on the text field, the clickHandler() method is invoked. It handles the starting and stopping of the sound file. Note that depending on the network connection or when the user clicks the Stop button, much of the file could already have been loaded and it may take a while for the sound file to stop playing. A try...catch block is used to catch any IO error that may occur while closing the stream. For example, if the sound is loaded from a local directory and not streamed, error 2029 is caught, stating, "This URLStream object does not have an open stream."

 
package {
    import flash.display.Sprite;
    import flash.net.URLRequest;
    import flash.media.Sound;    
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.events.MouseEvent;
    import flash.errors.IOError;
    import flash.events.IOErrorEvent;

    public class Sound_closeExample extends Sprite {
        private var snd:Sound = new Sound();
        private var button:TextField = new TextField();
        private var req:URLRequest = new URLRequest("http://av.adobe.com/podcast/csbu_dev_podcast_epi_2.mp3");
        
        public function Sound_closeExample() {
            button.x = 10;
            button.y = 10;
            button.text = "START";
            button.border = true;
            button.background = true;
            button.selectable = false;
            button.autoSize = TextFieldAutoSize.LEFT;

            button.addEventListener(MouseEvent.CLICK, clickHandler);

            this.addChild(button);
        }

        private function clickHandler(e:MouseEvent):void {

            if(button.text == "START") {

                snd.load(req);
                snd.play();        

                snd.addEventListener(IOErrorEvent.IO_ERROR, errorHandler);

                button.text = "STOP";
            }
            else if(button.text == "STOP") {
                    
                try {
                    snd.close();
                    button.text = "Wait for loaded stream to finish.";
                }
                catch (error:IOError) {
                    button.text = "Couldn't close stream " + error.message;    
                }
            }
        }
        
        private function errorHandler(event:IOErrorEvent):void {
                button.text = "Couldn't load the file " + event.text;
        }
    }
}


extract

()method 
public function extract(target:ByteArray, length:Number, startPosition:Number = -1):Number

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Extracts raw sound data from a Sound object.

This method is designed to be used when you are working with dynamically generated audio, using a function you assign to the sampleData event for a different Sound object. That is, you can use this method to extract sound data from a Sound object. Then you can write the data to the byte array that another Sound object is using to stream dynamic audio.

The audio data is placed in the target byte array starting from the current position of the byte array. The audio data is always exposed as 44100 Hz Stereo. The sample type is a 32-bit floating-point value, which can be converted to a Number using ByteArray.readFloat().

Parameters

target:ByteArray — A ByteArray object in which the extracted sound samples are placed.
 
length:Number — The number of sound samples to extract. A sample contains both the left and right channels — that is, two 32-bit floating-point values.
 
startPosition:Number (default = -1) — The sample at which extraction begins. If you don't specify a value, the first call to Sound.extract() starts at the beginning of the sound; subsequent calls without a value for startPosition progress sequentially through the file.

Returns
Number — The number of samples written to the ByteArray specified in the target parameter.

See also


Example  ( How to use this example )

The following example loads an mp3 file and uses the extract() method of the Sound class to access the audio data.

The mp3 data is loaded into the sourceSnd Sound object. When the application loads the mp3 data, it calls the loaded() function (the event handler for the complete event of the sourceSnd object). A second Sound object, outputSound, is used to play the modified audio. The outputSound object has a sampleData event listener; so the object dispatches periodical sampleData events once you call the play() method of the object. The upOctave() method returns a byte array of modified audio data based on the source audio data. It returns audio that is one octave higher by skipping over every other audio sample in the source data. The event handler for the sampleData event writes the returned byte array to the data property of the outputSound object. The data byte array is appended to the output audio data for the outputSound object.

To test this example, add a test.mp3 file to the same directory as the SWF file.


var sourceSnd:Sound = new Sound();
var outputSnd:Sound = new Sound();
var urlReq:URLRequest = new URLRequest("test.mp3");

sourceSnd.load(urlReq);
sourceSnd.addEventListener(Event.COMPLETE, loaded);

function loaded(event:Event):void
{
    outputSnd.addEventListener(SampleDataEvent.SAMPLE_DATA, processSound);
    outputSnd.play();
}

function processSound(event:SampleDataEvent):void
{
    var bytes:ByteArray = new ByteArray();
    sourceSnd.extract(bytes, 4096);
    event.data.writeBytes(upOctave(bytes));
}

function upOctave(bytes:ByteArray):ByteArray
{
    var returnBytes:ByteArray = new ByteArray();
    bytes.position = 0;
    while(bytes.bytesAvailable > 0)
    {
        returnBytes.writeFloat(bytes.readFloat());
        returnBytes.writeFloat(bytes.readFloat());
        if (bytes.bytesAvailable > 0)
        {
            bytes.position += 8;
        }
    }
    return returnBytes;
}

load

()method 
public function load(stream:URLRequest, context:SoundLoaderContext = null):void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Initiates loading of an external MP3 file from the specified URL. If you provide a valid URLRequest object to the Sound constructor, the constructor calls Sound.load() for you. You only need to call Sound.load() yourself if you don't pass a valid URLRequest object to the Sound constructor or you pass a null value.

Once load() is called on a Sound object, you can't later load a different sound file into that Sound object. To load a different sound file, create a new Sound object.

When using this method, consider the following security model:

  • Calling Sound.load() is not allowed if the calling file is in the local-with-file-system sandbox and the sound is in a network sandbox.
  • Access from the local-trusted or local-with-networking sandbox requires permission from a website through a URL policy file.
  • You cannot connect to commonly reserved ports. For a complete list of blocked ports, see "Restricting Networking APIs" in the security chapter security chapter of the Programming ActionScript 3.0 book.
  • You can prevent a SWF file from using this method by setting the allowNetworking parameter of the object and embed tags in the HTML page that contains the SWF content.

In Flash Player 10 and later, if you use a multipart Content-Type (for example "multipart/form-data") that contains an upload (indicated by a "filename" parameter in a "content-disposition" header within the POST body), the POST operation is subject to the security rules applied to uploads:

  • The POST operation must be performed in response to a user-initiated action, such as a mouse click or key press.
  • If the POST operation is cross-domain (the POST target is not on the same server as the SWF file that is sending the POST request), the target server must provide a URL policy file that permits cross-domain access.

Also, for any multipart Content-Type, the syntax must be valid (according to the RFC2046 standards). If the syntax appears to be invalid, the POST operation is subject to the security rules applied to uploads.

In Adobe AIR, content in the application security sandbox (content installed with the AIR application) are not restricted by these security limitations.

For more security-related information, see the following:

  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The "Understanding AIR Security" section of the "Getting started with Adobe AIR" chapter in the Developing AIR Applications book.
  • The Flash Player Developer Center Topic: Security

Parameters

stream:URLRequest — A URL that points to an external MP3 file.
 
context:SoundLoaderContext (default = null) — An optional SoundLoader context object, which can define the buffer time (the minimum number of milliseconds of MP3 data to hold in the Sound object's buffer) and can specify whether the application should check for a cross-domain policy file prior to loading the sound.


Throws
IOError — A network error caused the load to fail.
 
SecurityError — Local untrusted files may not communicate with the Internet. You can work around this by reclassifying this file as local-with-networking or trusted.
 
SecurityError — If you are trying to connect to a commonly reserved port. For a complete list of blocked ports, see "Restricting Networking APIs" in the security chapter of the Programming ActionScript 3.0 book.
 
IOError — The digest property of the stream object is not null. You should only set the digest property of a URLRequest object when calling the URLLoader.load() method when loading a SWZ file (an Adobe platform component).
 
SecurityError — If you are trying to connect to a commonly reserved port. For a complete list of blocked ports, see "Restricting Networking APIs" in the security chapter of the Programming ActionScript 3.0 book.

Example  ( How to use this example )

The following example displays the loading progress of a sound file.

In the constructor a URLRequest object is created to identify the location of the sound file, which is a podcast from Adobe. The file is loaded in a try...catch block in order to catch any error that may occur while loading the file. If an IO error occurred, the errorHandler() method also is invoked and the error message is written in the text field intended for the progress report. While a load operation is in progress, a ProgressEvent.PROGRESS event is dispatched and the progressHandler() method is called. Here, ProgressEvent.PROGRESS event is used as a timer for calculating the load progress.

The progressHandler() method divides the bytesLoaded value passed with the ProgressEvent object by the bytesTotal value to arrive at a percentage of the sound data that is being loaded. It then displays these values in the text field. (Note that if the file is small, cached, or the file is in the local directory, the progress may not be noticeable.)

package {
    import flash.display.Sprite;
    import flash.net.URLRequest;
    import flash.media.Sound;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.events.ProgressEvent;
    import flash.events.IOErrorEvent;
    
    public class Sound_loadExample extends Sprite {
        private var snd:Sound = new Sound();
        private var statusTextField:TextField  = new TextField();

        public function Sound_loadExample(){

            statusTextField.autoSize = TextFieldAutoSize.LEFT;
            var req:URLRequest = new URLRequest("http://av.adobe.com/podcast/csbu_dev_podcast_epi_2.mp3");
            
            try {
            snd.load(req);
            
            snd.play();
            }
            catch (err:Error) {
                trace(err.message);
            }
 
            snd.addEventListener(IOErrorEvent.IO_ERROR, errorHandler);
            snd.addEventListener(ProgressEvent.PROGRESS, progressHandler);
                     
            this.addChild(statusTextField);
        }
    
        private function progressHandler(event:ProgressEvent):void {
            var loadTime:Number = event.bytesLoaded / event.bytesTotal;
            var LoadPercent:uint = Math.round(100 * loadTime);
              
            statusTextField.text = "Sound file's size in bytes: " + event.bytesTotal + "\n" 
                                 + "Bytes being loaded: " + event.bytesLoaded + "\n" 
                                 + "Percentage of sound file that is loaded " + LoadPercent + "%.\n";
        }
 
        private function errorHandler(errorEvent:IOErrorEvent):void {
            statusTextField.text = "The sound could not be loaded: " + errorEvent.text;
        }
    }
}

play

()method 
public function play(startTime:Number = 0, loops:int = 0, sndTransform:flash.media:SoundTransform = null):SoundChannel

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Generates a new SoundChannel object to play back the sound. This method returns a SoundChannel object, which you access to stop the sound and to monitor volume. (To control the volume, panning, and balance, access the SoundTransform object assigned to the sound channel.)

Parameters

startTime:Number (default = 0) — The initial position in milliseconds at which playback should start.
 
loops:int (default = 0) — Defines the number of times a sound loops back to the startTime value before the sound channel stops playback.
 
sndTransform:flash.media:SoundTransform (default = null) — The initial SoundTransform object assigned to the sound channel.

Returns
SoundChannel — A SoundChannel object, which you use to control the sound. This method returns null if you have no sound card or if you run out of available sound channels. The maximum number of sound channels available at once is 32.

See also


Example  ( How to use this example )

In the following example, once the file is loaded, the user using a graphic bar can select the starting position (starting time) of the sound file.

The constructor calls the Sound.load() method to start loading the sound data. Next it calls the Sound.play() method which will start playing the sound as soon as enough data has loaded. The Sound.play() method returns a SoundChannel object that can be used to control the playback of the sound. The text field displays the instructions. To make sure the content of where the user wants the sound to start, has already been loaded, the bar Sprite object is created and displayed after the file has finished loading. An Event.COMPLETE event is dispatched when the file is successfully loaded, which triggers the completeHandler() method. The completeHandler() method then creates the bar and adds it to the display list. (A sprite object is used instead of a shape object to support interactivity.) When the user clicks on the bar, the clickHandler() method is triggered.

In the clickHandler() method, the position of x coordinate of the user's click, event.localX, is used to determine where the user wants the file to start. Since the bar is 100 pixels and it starts at x coordinate 100 pixels, it is easy to determine the percentage of the position. Also, since the file is loaded, the length property of the sound file will have the length of the complete file in milliseconds. Using the length of the sound file and the position in the line, a starting position for the sound file is determined. After stopping the sound from playing, the sound file restarts at the selected starting position, which is past as the startTime parameter to the play() method.

 
package {
    import flash.display.Sprite;
    import flash.display.Graphics;
    import flash.events.MouseEvent;
    import flash.media.Sound;;
    import flash.net.URLRequest;
    import flash.media.SoundChannel;
    import flash.events.ProgressEvent;
    import flash.events.Event;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.events.IOErrorEvent;
    
    public class Sound_playExample1 extends Sprite {
        private var snd:Sound = new Sound();
        private var channel:SoundChannel = new SoundChannel();
        private var infoTextField:TextField = new TextField();
    
        public function Sound_playExample1() {

            var req:URLRequest = new URLRequest("MySound.mp3");
            
            infoTextField.autoSize = TextFieldAutoSize.LEFT;
            infoTextField.text = "Please wait for the file to be loaded.\n" 
                                + "Then select from the bar to decide where the file should start.";
            
            snd.load(req);               
            channel = snd.play();

            snd.addEventListener(IOErrorEvent.IO_ERROR, errorHandler);
            snd.addEventListener(Event.COMPLETE, completeHandler);


            this.addChild(infoTextField);
        }

        private function completeHandler(event:Event):void {                
            infoTextField.text = "File is ready.";

            var bar:Sprite = new Sprite();

            bar.graphics.lineStyle(5, 0xFF0000);
            bar.graphics.moveTo(100, 100);
            bar.graphics.lineTo(200, 100);

            bar.addEventListener(MouseEvent.CLICK, clickHandler);

            this.addChild(bar);
        }
    
        private function clickHandler(event:MouseEvent):void {
            
                var position:uint = event.localX;
                var percent:uint = Math.round(position) - 100;   
                var cue:uint = (percent / 100) * snd.length;

                channel.stop();
                channel = snd.play(cue);    
        }

        private function errorHandler(errorEvent:IOErrorEvent):void {
            infoTextField.text = "The sound could not be loaded: " + errorEvent.text;
        }
    }
}

In the following example, depending on whether the user single or double clicks on a button the sound will play once or twice.

In the constructor, the sound is loaded and a simple rectangle button sprite object is created. (A sprite object is used instead of a shape object to support interactivity.) Here, it is assumed that the sound file is in the same directory as the SWF file. (There is no error handling code for this example.)

Two event listeners are set up to respond to single mouse clicks and double clicks. If the user clicks once, the clickHandler() method is invoked, which plays the sound. If the user double clicks on the button, the doubleClickHandler() method is invoked, which will play the sound file twice. The second argument of the play() method is set to 1, which means the sound will loop back once to the starting time of the sound and play again. The starting time, first argument, is set to 0, meaning the file will play from the beginning.

package {
    import flash.display.Sprite;
    import flash.events.MouseEvent;
    import flash.media.Sound;
    import flash.net.URLRequest;

    public class Sound_playExample2 extends Sprite {
        private var button:Sprite = new Sprite(); 
        private var snd:Sound = new Sound();
            
        public function Sound_playExample2() {

            var req:URLRequest = new URLRequest("click.mp3");
            snd.load(req);               
     
            button.graphics.beginFill(0x00FF00);
            button.graphics.drawRect(10, 10, 50, 30);
            button.graphics.endFill();
     
            button.addEventListener(MouseEvent.CLICK, clickHandler);
            button.addEventListener(MouseEvent.DOUBLE_CLICK, doubleClickHandler);
     
            this.addChild(button);
        }

        private function clickHandler(event:MouseEvent):void {
            snd.play();            
        }

        private function doubleClickHandler(event:MouseEvent):void {
            snd.play(0, 2);        
        }
    }
}

The following example displays the loading and playing progress of a sound file.

In the constructor, the file is loaded in a try...catch block in order to catch any error that may occur while loading the file. A listener is added to the sound object that will respond to an IOErrorEvent event by calling the errorHandler() method. Another listener is added for the main application that will respond to an Event.ENTER_FRAME event, which is used as the timing mechanism for showing playback progress. Finally, a third listener is added for the sound channel that will respond to an Event.SOUND_COMPLETE event (when the sound has finished playing), by calling the soundCompleteHandler() method. The soundCompleteHandler() method also removes the event listener for the Event.ENTER_FRAME event.

The enterFrameHandler() method divides the bytesLoaded value passed with the ProgressEvent object by the bytesTotal value to arrive at a percentage of the sound data that is being loaded. The percentage of sound data that is being played could be determined by dividing the value of sound channel's position property by the length of the sound data. However, if the sound data is not fully loaded, the length property of the sound object shows only the size of the sound data that is currently loaded. An estimate of the eventual size of the full sound file is calculated by dividing the value of the current sound object's length by the value of the bytesLoaded property divided by the value of the bytesTotal property.

Note that if the file is small, cached, or the file is in the local directory, the load progress may not be noticeable. Also the lag time between when the sound data starts loading and the loaded data starts playing is determined by the value of the SoundLoaderContext.buffertime property, which is by default 1000 milliseconds and can be reset.

package {
    import flash.display.Sprite;
    import flash.net.URLRequest;
    import flash.media.Sound;
    import flash.media.SoundChannel;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.events.Event;
    import flash.events.IOErrorEvent;
    
    public class Sound_playExample3 extends Sprite {
        private var snd:Sound = new Sound();
        private var channel:SoundChannel;
        private var statusTextField:TextField  = new TextField();

        public function Sound_playExample3(){

            statusTextField.autoSize = TextFieldAutoSize.LEFT;

           var req:URLRequest = new URLRequest("http://av.adobe.com/podcast/csbu_dev_podcast_epi_2.mp3");
            
            try {
                snd.load(req);
            
                channel = snd.play();
            }
            catch (err:Error) {
                trace(err.message);
            }
                    
            snd.addEventListener(IOErrorEvent.IO_ERROR, errorHandler);
            addEventListener(Event.ENTER_FRAME, enterFrameHandler);
            channel.addEventListener(Event.SOUND_COMPLETE, soundCompleteHandler);
                    
            this.addChild(statusTextField);
        }
    
        private function enterFrameHandler(event:Event):void {    
            var loadTime:Number = snd.bytesLoaded / snd.bytesTotal;
            var loadPercent:uint = Math.round(100 * loadTime);
            var estimatedLength:int = Math.ceil(snd.length / (loadTime));
            var playbackPercent:uint = Math.round(100 * (channel.position / estimatedLength));
      
            statusTextField.text = "Sound file's size is " + snd.bytesTotal + " bytes.\n" 
                                   + "Bytes being loaded: " + snd.bytesLoaded + "\n" 
                                   + "Percentage of sound file that is loaded " + loadPercent + "%.\n"
                                   + "Sound playback is " + playbackPercent + "% complete.";     
        }
 
        private function errorHandler(errorEvent:IOErrorEvent):void {
            statusTextField.text = "The sound could not be loaded: " + errorEvent.text;
        }

        private function soundCompleteHandler(event:Event):void {
            statusTextField.text = "The sound has finished playing.";
            removeEventListener(Event.ENTER_FRAME, enterFrameHandler);
        }
    }
}
Event Detail

complete

Event
Event Object Type: flash.events.Event
property Event.type = flash.events.Event.COMPLETE

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched when data has loaded successfully.

The Event.COMPLETE constant defines the value of the type property of a complete event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe network object that has completed loading.

See also

id3

Event  
Event Object Type: flash.events.Event
property Event.type = flash.events.Event.ID3

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched by a Sound object when ID3 data is available for an MP3 sound.

The Event.ID3 constant defines the value of the type property of an id3 event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe Sound object loading the MP3 for which ID3 data is now available. The target is not always the object in the display list that registered the event listener. Use the currentTarget property to access the object in the display list that is currently processing the event.

See also

ioError

Event  
Event Object Type: flash.events.IOErrorEvent
property IOErrorEvent.type = flash.events.IOErrorEvent.IO_ERROR

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched when an input/output error occurs that causes a load operation to fail.

Defines the value of the type property of an ioError event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
errorIDA reference number associated with the specific error (AIR only).
targetThe network object experiencing the input/output error.
textText to be displayed as an error message.

See also

open

Event  
Event Object Type: flash.events.Event
property Event.type = flash.events.Event.OPEN

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched when a load operation starts.

The Event.OPEN constant defines the value of the type property of an open event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe network object that has opened a connection.

See also

progress

Event  
Event Object Type: flash.events.ProgressEvent
property ProgressEvent.type = flash.events.ProgressEvent.PROGRESS

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched when data is received as a load operation progresses.

Defines the value of the type property of a progress event object.

This event has the following properties:

PropertyValue
bubblesfalse
bytesLoadedThe number of items or bytes loaded at the time the listener processes the event.
bytesTotalThe total number of items or bytes that ultimately will be loaded if the loading process succeeds.
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe object reporting progress.

See also

sampleData

Event  
Event Object Type: flash.events.SampleDataEvent
property SampleDataEvent.type = flash.events.Event.SAMPLE_DATA

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Dispatched when the player requests new audio data.


Example  ( How to use this example )

The following example plays a simple sine wave.
var mySound:Sound = new Sound();
function sineWaveGenerator(event:SampleDataEvent):void {
    for ( var c:int=0; c<8192; c++ ) {
        event.data.writeFloat(Math.sin((Number(c+event.position)/Math.PI/2))*0.25);
        event.data.writeFloat(Math.sin((Number(c+event.position)/Math.PI/2))*0.25);
    }
}

mySound.addEventListener(Event.SAMPLE_DATA,sineWaveGenerator);
mySound.play();

See also

SoundExample.as

The following example displays information about sound events that take place as an MP3 file is opened and played. To run this example, place a file named MySound.mp3 in the same directory as your SWF file.
package {
    import flash.display.Sprite;
    import flash.events.*;
    import flash.media.Sound;
    import flash.media.SoundChannel;
    import flash.net.URLRequest;

    public class SoundExample extends Sprite {
        private var url:String = "MySound.mp3";
        private var song:SoundChannel;

        public function SoundExample() {
            var request:URLRequest = new URLRequest(url);
            var soundFactory:Sound = new Sound();
            soundFactory.addEventListener(Event.COMPLETE, completeHandler);
            soundFactory.addEventListener(Event.ID3, id3Handler);
            soundFactory.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
            soundFactory.addEventListener(ProgressEvent.PROGRESS, progressHandler);
            soundFactory.load(request);
            song = soundFactory.play();
        }

        private function completeHandler(event:Event):void {
            trace("completeHandler: " + event);
        }

        private function id3Handler(event:Event):void {
            trace("id3Handler: " + event);
        }

        private function ioErrorHandler(event:Event):void {
            trace("ioErrorHandler: " + event);
        }

        private function progressHandler(event:ProgressEvent):void {
            trace("progressHandler: " + event);
        }
    }
}