Changes in id/name handling!?

Question

On my search to find a good way to compensate the lack of event triggers with the new Animate effects I encoutered a strange problem. A really basic one
So I have an empty application with a button like this (simplyfied):
<s:Application>
<s:Button id="myButton" click="trace(event.target)" />
</s:Application>
When i click the Button I would expect it to trace something like
app.ApplicationSkin2.Group3.myButton
but instead i get
EventSanityCheck0.ApplicationSkin2.Group3.Button4
just some auto generated Button4 identifier!?
Seems like my identifier is lost somehow. It turns out that if I set the name property of my Button like so:
<s:Button name="myButton" click="trace(event.target)" /> it actually gives me the correct name in the trace.
This is not really what one would expect or? It certainly was different in Flex 3 and I don`t think it makes sense. The identifier should be the identifier or?
What is the difference between name and id anyway? In Flex3 it made sense but now it`s treated in a different way I think?
From the manual:
name = Indicates the instance name of the DisplayObject.
id = ID of the component. This value becomes the instance name of the object
I get the feeling I`m asking something really dumb here - just need to do a sanity check
BTW I have much more probems with events and objects in a group but first need to sort this out
Thanks for any clarifications on these changes.
Benz

Answer 1

Nope, you aren't asking anything dumb.
So with the Flex 4 containers (including s:Application), the compiler no longer generates UIComponentDescriptors representing each node in your MXML document.
Why is this meaningful?
In Flex 3 the compiler would generate a UIComponentDescriptor representation of each component tag in your document.  At runtime these component descriptors would be realized into actual instances.  See Container::createComponentFromDescriptor ... In this method the 'name' would be set (copied) from the id of the component.
In Flex 4 the compiler instead generates factory methods for each component tag in your document.  These are a bit faster.  In this case we don't go through the step of copying the id to the name field (if name is unspecified).
You can compile your sample with '-keep' to contrast the difference in code generation to see for yourself what I'm referring to.
Feel free to file an enhancement request in JIRA (I believe it would be valuable to address) - http://bugs.adobe.com/flex/.  But for now you'll need to assign a meaningful name yourself if you wish to your name to reflect the id moniker.
Regards,
Corey Lucier