Issues with mx:method, mx.rpc.remoting.mxml.RemoteObject, and sub-classing mx.rpc.remoting.mxml.RemoteObject

Question

I am looking to subclass RemoteObject. Instead of:

<mx:RemoteObject ... >
    <mx:method ... />
    <mx:method ... />
</mx:RemoteObject>

I want to do something like:

<remoting:CustomRemoteObject ...>
    <mx:method ... />
    <mx:method ... />
</remoting:CustomRemoteObject>

where CustomRemoteObject extends mx.rpc.remoting.mxml.RemoteObject like so:

package remoting
{
    import mx.rpc.remoting.mxml.RemoteObject;

    public class CustomRemoteObject extends RemoteObject
    {
        public function CustomRemoteObject(destination:String=null)
        {
            super(destination);
        }
    }
}

However, when doing so and declaring a CustomRemoteObject in MXML as above, the flex compiler shows the error:

Could not resolve <mx:method> to a component implementation

At first I thought it had something to do with CustomRemoteObject failing to do something, despite that (or since) it had no change except as to the name. So, I copied the source from mx.rpc.remoting.mxml.RemoteObject into CustomRemoteObject and modified it so the only difference was a refactoring of the class and package name. But still, the same error.

Unlike many MXML components, I cannot cmd+click <mx:method> in FlashBuilder to open the source. Likewise, I have not found a reference in mx.rpc.remoting.mxml.RemoteObject, mx.rpc.remoting.RemoteObject, or mx.rpc.remoting.AbstractService, and have been unsuccessful in find its source online.

Which leads me to the questions in the title:

What exactly is <mx:method>? (yes, I know it's a declaration of a RemoteObject method, and I know how to use it, but it's peculiar in regard to other components)

Why did my attempt at subclassing RemoteObject fail, despite it effectually being a rename? Perhaps the root, why can mx.rpc.remoting.mxml.RemoteObject as an MXML declaration accept <mx:method> child tags, yet the source of said class cannot when refactored in name only?

Answer 1

The syntax you're looking at ('mx:method') is a way to define properties in MXML instead of in ACtionScript. IF this were extending a "standard" UIComponent, you'd do this:

<remoting:CustomRemoteObject ...>
    <remoting:method ... />
    <remoting:method ... />
</remoting:CustomRemoteObject>

However, since method is not a property on RemoteObject, there is probably some compiler magic behind the scenes. I bet it turns the "methods" tags into the operation array.

You'll probably need to do that manually, something like this:

<remoting:CustomRemoteObject ...>
  <remoting:Operations>
    <remoting:method ... />
    <remoting:method ... />
   </remoting:Operations>
</remoting:CustomRemoteObject>

But, you may have to parse through code and/or run in debug mode and/or review the generated actionscript to figure out exactly what is going on and how "method" is turned into the operations array.

I thought the source of the remoting classes was available in the SDK; but perhaps just the open source SDK not the Adobe supported SDK. You can download the open source SDK at opensource.adobe.com

Half of this post is guessing.