Af:region, PPR and onload handler

Question

We develop custom JSF components that need some javascript counterpart on the client.
These counterparts needs to be initialized (through some AJAX calls) when the page is ready to be displayed.
In old technologies, this was done through an "onload" javascript handler placed on the page.
In Apache Trinidad PPR, the page is already loaded when the components are rendered, and we need to register those scripts at render time (in encodeEnd) through :
ExtendedRenderKitService service =  Service.getRenderKitService(context, ExtendedRenderKitService.class); 
service.addScript(context, jsMethod);This method is available in ADF, so we can reuse this.
However, since the default onload mechanism already calls the scripts, and we want the scripts to be called only once, we need to make sure we are in a PPR context by using something like
reqContext.isPartialRequest(context);Now, in an af:region use case, we are not really in a PPR rendering (isPartialRequest returns false). What API should I use to check that the page is already loaded and we are just rendering a new region in that page ?

Answer 1

I tried the AdfFacesContext.getCurrentInstance().isInitialRender() through layers of reflection, to keep independent at compile time from ADF.
However, even when this "initialRender" flag is true, the page rendering (client side) still goes through ADF AJAX calls and does not happen directly in the browser window.
I need in fact to detect, server side, whether the HTML I'm rendering will be executed directly in the browser (in that case, the "onload" happens) or through some indirection on the client where DOM elements such as "document" or "window" may not exist. In the latter case, I will register a script through the ExtendedRenderKitService class.
Any idea on the way I can do this in case of an af:region ?