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Regardless if you Flex or Flash, I ran into a porting issue with a Flashcom app I wrote in Flex 1.5 & ActionScript 2. A lot of the server-side code, which is written in case sensitive JavaScript 1, utilizes the Flashcom Component Framework. This framework utilizes a namespace scheme to allow clients to identify server components, and server components to identify client components. This allows them to send messages to each other, and works really well…

…except in Flash Player 9. For some reason, the namespace mechanism doesn’t work for ActionScript 3 classes. This isn’t a big deal for playing existing content. All of my existing Flashcom apps I wrote in Flash MX 2004 & Flex 1.5 (Flash Player 7) still run just fine in Flash Player 9 in both Firefox & IE.

It’s when you have a server-side script do a NetConnection.call on an Flash Player 9 created SWF that things don’t work. You CAN call a method that your class has defined as public assuming you point the NetConnection’s client property to your class; protected and private don’t work. However, the namespace mechanism commonly used in ActionScript 2 doesn’t work with the server; it constantly reports method not found. You’d typically decorate the client side NetConnection object reference that you’re component got passed in via it’s loose interface “connect” method. This decoration with the namespaces pointing to your component allowed the server-side to find it. The server-side Flashcom Component Framework already has a built-in namespace mechanism that still works just fine.

You can emulate this by extending NetConnection, and making the class dynamic. Still, you’ll get the method not found error.

My only guess at the problem is I think it has to do with the lack of support of “slash syntax”. I’m not sure the new ActionScript Virtual Machine supports it. I know AVM does; it’s how Flash Player 4 SWF’s will work the same as they always have. However, it seems the FCS Component Framework utilizes this behind the scenes somehow. When you do this on the server-side:

nc.call ( this.callPrefix + "method" );

You’re basically going:

nc.call ( "YourComponent/InstanceName/method" );

…I guess. I gave up after 3 nights of trying to get it to work. I didn’t mind porting client code, but I didn’t want to port server-side code. Anyway, fix for me is to pass in the callPrefix as the first parameter to the method, and have the client side Observer class just parse out “who this message goes to”.

If you get it to work on your end, drop a note in the comments. I’m using Flex 2 & FCS 1.5 on Windows via Flash Player 9 in Firefox 1.5.

Past two weeks, I’ve been porting over some Flashcom & Flex 1.5 code to Flex 2 (still using FCS 1.5 vs. FMS 2). One nice addition I found in the ActionScript 3 SharedObject class is the client property. This little gem allows you have events that are called by SharedObject.send to be called on a proxy class instead. What this means is, if someone in a Flashcom application causes the remote SharedObject to be updated, and it fires a “onChatMessageUpdate” method, it’ll actually get called on the client object if you set it to something. Since a lot of intrinsic classes are now “final”, meaning you can’t futz with ‘em as easily as you could in AS2, this is a great way to incorporate it via Composition.

var my_rso:SharedObject = SharedObject.getRemote("chat", nc.uri, false);
my_rso.owner = this;
my_rso.onChat = function(str)
{
        this.owner.onChatMessage(str);
};

function onChatMessage(str)
{
        textArea.text += str;
}

In the past, you’d use something like the above; proxying the message yourself, or even putting the logic inside the method closure if you were in a hurry.

Now, you can forward it to an anonymous object, yourself, or even a class instance.

var my_rso:SharedObject = SharedObject.getRemote("chat", nc.uri, false);
my_rso.client = this; // onChatMessage needs to be a public function in this class
my_rso.client = {onChatMessage: function(str){ // }}; // anonymous function
                my_rso.client = new ProxyClass(); // you can make a class specifically to handle events

David Simmons from Adobe told me it was on NetConnection as well. Just checked, and she’s on NetStream too. In my tests, for classes, it only works on methods in the public namespace; protected & private don’t work. I didn’t test custom namespaces, nor do I know how to make it “see” them.

Handy! Thanks Adobe.