ExternalInterface callback is undefined AS3

Question

I am new to AS3, and would like to trigger an as3 function from javascript.

AS3

package code {
    import flash.display.MovieClip;
    import flash.external.ExternalInterface;
    import flash.text.TextFormat;

    public class Main extends MovieClip {
        public function Main() {
            ExternalInterface.addCallback("changesize", this.setStyle);
        }

        protected function setStyle() {
            var tf:TextFormat = new TextFormat();
            tf.size = 15;

            editabletext.setTextFormat(tf);
        }
    }
}

html

    <html><head>
            <meta charset="UTF-8">
            <title>animator</title>
            <style type="text/css" media="screen">
            html, body { height:100%; background-color: #ffffff;}
            body { margin:0; padding:0; overflow:hidden; }
            #flashContent { width:100%; height:100%; }
            </style>
        </head>
        <body>
            <div id="flashContent">
                <object type="application/x-shockwave-flash" data="animator.swf" width="550" height="400" id="animator" style="float: none; vertical-align:middle">
                    <param name="movie" value="animator.swf">
                    <param name="quality" value="high">
                    <param name="bgcolor" value="#ffffff">
                    <param name="play" value="true">
                    <param name="loop" value="true">
                    <param name="wmode" value="window">
                    <param name="scale" value="showall">
                    <param name="menu" value="true">
                    <param name="devicefont" value="false">
                    <param name="salign" value="">
                    <param name="allowScriptAccess" value="always">
                    <a href="http://www.adobe.com/go/getflash">
                        <img src="http://www.adobe.com/images/shared/download_buttons/get_flash_player.gif" alt="Get Adobe Flash player">
                    </a>
                </object>
            </div>

        <script type="text/javascript">
            var animator = document.getElementById('animator');
            animator.changesize();
        </script>

    </body></html>

animator.changesize() gives me Uncaught TypeError: animator.changesize is not a function

I have also tried changing allowscript access between sameDomain and always. neither seems to work

Maybe ExternalInterface.available is false, if so, you won't get external callbacks. Also it's possible that you call the callback before your SWF is initialized the callback on its side. — Vesper
if you are testing locally it won't work, try to test it in a remote server — Özgür Ersil

Aaron Beall Aaron Beall · Accepted Answer · 2015-07-09T22:48:51

It's a timing issue. The callback will only get added to the DOM once the SWF has been loaded by the Flash Player and the Main constructor is executed, but you are trying to call it immediately when the DOM is parsed.

Since the DOM is always going to be parsed before the SWF is loaded (and the callback is added) you should not assume that the SWF callback is always there and ready to be called. Instead, the SWF should call into JS when it is ready.

ExternalInterface callback is undefined AS3

2 Answers