javascriptactionscriptexternalinterfacenomethoderror

Accessing an ActionScript function via Javascript

I'm trying to call a function in an action script using the ExternalInterface.addCallback API, but I can't seem to get it to work. Here's what I have:

ActionScript:

//MyClass.as  
package {

    import flash.display.Sprite;
    import flash.external.ExternalInterface;

    public class MyClass extends Sprite
    {
        public function MyClass()
        {
            ExternalInterface.addCallback('getStringJS', getStringAS);
        }

        public function getStringAS():String
        {
            return "Hello World!";
        }
    }
}

NOTE: I'm compiling this into an swf using the flex mxmlc compiler if that matters.

HTML/Javascript:

<!doctype html>
<html>
    <head>
        <title>User Identification</title>
    <head>
    <body>
        <object id="MyClass" name="MyClass" type="application/x-shockwave-flash" data="MyClass.swf" width="1" height="1">
            <param name="movie" value="MyClass.swf">
            <embed src="MyClass.swf" width="1" height="1">
        </object>
        <script type="text/javascript">
            var flash = document.getElementById("MyClass");
            var str = flash.getStringJS();
            alert(str);
        </script>
    </body>
</html>

The error I'm getting is:

Uncaught TypeError: Object #<HTMLObjectElement> has no method 'getStringJS'

I also tried adding in a timeout in case the swf file wasn't loading, but I didn't have any success with that method either.

Any thoughts?

Cheers,
Mike

Solution

  • I figured it out. The key way to signal the javascipt through ExternalInterface.call so we know for sure that the swf is loaded. The most "Universal" way to do this is as follows:

    MyClass.as

    //MyClass.as  
package {

    import flash.display.Sprite;
    import flash.external.ExternalInterface;

    public class MyClass extends Sprite
    {
        public function MyClass()
        {
            ExternalInterface.addCallback('getStringJS', getStringAS);
            if  (ExternalInterface.available) {
                ExternalInterface.call("isConnectedFlex");
            }
        }

        public function getStringAS():String
        {
            return "Hello World!";
        }
    }
}

    index.html

    <!doctype html>
<html>
    <head>
        <title>User Identification</title>
    <head>
    <body>
        <object id="MyClass" name="MyClass" type="application/x-shockwave-flash" data="MyClass.swf" width="1" height="1">
            <param name="movie" value="MyClass.swf">
            <embed src="MyClass.swf" width="1" height="1">
        </object>
        <script type="text/javascript">

            var flash = document.getElementById("MyClass");

            function isConnectedFlex() {
                var str = flash.getStringJS();
                alert(str);
            }


        </script>
    </body>
</html>