Question

Basically I created a simple mp3 player, and there are multiple copies of that embedded in a page. Now when I play one, I want all the others to pause…..any idea how to do this? is it possible to do n-way localconnection? or is there a better alternative?

Answer 1

ExternalInterface.call can be used to call JavaScript from a SWF and, vice-versa, ExternalInterface.addCallback can be used to expose certain methods to be called by JavaScript.

For example, in each SWF, you might have:

ExternalInterface.addCallback("externalStopAudio", stopAudio);

// later..
function stopAudio():void {
    // Code to stop audio
    _audioStream.stop(); 
}

function playAudio():void {
    // tell JS to stop all audio
    ExternalInterface.call("stopAllAudio");
    // play this players audio
    _audioStream.play();
}

And then in the JS that is part of the HTML containing the SWF:

<script>
    // these references need to be actual pointers to the SWFs, this will vary 
    // depending on how you have it setup - might be SWFObject, Jquery, etc
    var a = [swf1, swf2, swf3];

    // called by SWF
    function stopAllAudio() {
        // called to SWF
        for(var i = 0; i < a.length; i++) {
             a[i].externalStopAudio();
        }
    }

</script>

Depending on security settings/domain placement, you may need the following:

In HTML:

<param name="allowScriptAccess" value="always" />

In SWF:

flash.system.Security.allowDomain(sourceDomain)

See: http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/external/ExternalInterface.html#addCallback%28%29