[Wonder-disc] addResourceInHead and AjaxUpdateContainers

[<aro...@cl...>]

Hi Guys,

We really love the "addXXXResourceInHead" methods such as 
"addStylesheetResourceInHead". It's really neat to design a reusable 
subComponent and just think about what resources it needs (CSS, 
Javascript, etc). Then, in that subComponent's "appendToResponse()" method 
you can simply call those resourceInHead methods so that the appropriate 
resources are only mentioned once in between the "head" tags.

As cool as this is, we've run into a snag. I wonder if anyone else has 
stumbled on this and has an elegant solution. 

The Problem:
If there are no instances of your special reuseable subComponent displayed 
at page load time, there is no reference to their mandatory CSS and 
Javascript resources in between the header tags. But, by the result of an 
Ajax call, when a portion of the DOM gets updated and your reuseable 
subComponent appears, it will lack its necessary CSS and Javascript to 
function properly.

The Reason:
"appendToResponse()" was not called on the reusable subComponent at page 
load. That was its only chance to stick its required resources inbetween 
the "head" tags. When you use an AjaxUpdateContainer to replace part of 
the DOM, you do call that subComponent's "appendToResponse()" method but 
there is no "head" tag and hence no place to stick your required 
resources.

The Workaround:
The current workaround we have in place right now is to put some of these 
resources in our "page wrapper" component. This is not so elegant because 
the reusable subComponent is no longer self contained.

The Solution:
Please extrapolate any ideas you might have on this curious situation :-)

Cheers,
-- Aaron