historically the components you add from auto resolvers are added via
the autoAdd() method, not using add(). these components only exist
during render of the page (in detach() phase all auto-added components
are removed). the thinking here is that auto resolved components are
not normal components. because they are resolved so late in the
lifecycle they do not typically implement the entire lifecycle like
onInitialize(), onConfigure(), etc may not necessarily be called. such
components are also not meant to have their own state. because of
these reasons we remove them at the end of the request and readd a new
instance next time the page is rendered. these are basically
"transient" "render-once" components.

starting with wicket 1.5, however, components are able to resole their
markup earlier in their lifecycle. the reason auto resolved components
are added so late and treated specially was because the markup was
only available during render.  if you are using 1.5 or 6 you can build
your own mechanism. something that kicks off a page/panel's
oninitialize(), gets the markup, walks it, and adds any components -
maybe ones you mark by special tags in your own namespace. the problem
here is that even if you can find these components you may still not
be able to put them into the right parent because in onInitialize()
the parent may not yet be added to the container. so perhaps you
should have some mechanism that kicks off when page#onComponentAdded()
is called. you can pull the newly added component's markup, see if it
has any of these special components defined as a child of the
components markup, and add them right there. since you are doing this
early on these components will have normal lifecycle and should work
just like any other component.

hope this helps you get started. keep us in the loop.

-igor


On Thu, Nov 22, 2012 at 4:54 PM, Chris Colman
<chr...@stepaheadsoftware.com> wrote:
> We've been using Wicket since version 1.3 and have been using the
> IComponentResolver interface with great effect to allow the web
> designers to effectively 'plug and play' with the Wicket components.
>
> We have multiple layouts using Wicket's 'variation' feature. Each
> designer can build up a different collection of components in any
> particular variation as they like - all without changing the Java code.
>
> Normally, without using IComponentResolver, the Java code to support
> such flexibility would be mind boggingly complex and ugly but with an
> IComponentResolver we simply have code that's capable of instantiating
> any component anywhere - and it works and the resulting code is
> extremely elegant.
>
> While we use lots of AJAX it is restricted to components that are
> explicitly added to components i.e. not added dynamically via the
> component resolver because such components are not able to contribute
> anything to the <head> section.
>
> This is starting to become a bit of a problem as we want some of the
> more advanced components (with AJAX) to take part in the 'plug and play'
> flexibility. We also are starting to get into using Twitter Bootstrap
> with Wicket and much of the 'funkiness' in some of those components
> comes from JS that needs to be injected into the header.
>
> Is anyone else using this 'plug and play' capability of Wicket made
> available via the IComponentResolver interface or is everyone sticking
> to the rigid 1 to 1 relationship between markup and the corresponding
> statically coded Java component hierarchy? (which we found quite
> constricting after a few weeks =] )
>
> I understand that there are some workarounds suggested for empowering
> AJAX in dynamically added components but they seem to involve manually
> parsing markup in the onInitialize method and then explicitly adding any
> required components there - it sounds non ideal and would result in an
> extra parse of all page and panel markups I would think - which may
> affect performance. Would we be parsing raw XHTML at that stage or would
> a preparsed DOM be available to search through?
>
> What is the fundamental issue with the Wicket architecture that prevents
> dynamically resolved components from contributing to the header?
>
> Is one of the causes the fact that by the time the ComponentResolver is
> being called the header has already been rendered to the response stream
> and so once body rendering commences no more header injection is
> possible?
>
> If so, that could probably (thinking out aloud without an in depth
> knowledge of Wicket's internals =] ) be solved by splitting the
> rendering into two streams: header injection goes to current output
> stream while body rendering goes to a temporary 'body' stream. When the
> page render is complete the output of the body is then appended to the
> current stream, after the header rendering. This would allow header
> injection to continue during processing of the body markup because both
> are not being sequentially output to the same stream.
>
> There was mention of another issue - something about auto added
> (component resolver) objects being removed after rendering so they are
> not there when AJAX actions occur. I don't fully understand the details
> of this or why it is necessary. Maybe this devs could offer more advice
> on this.

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