Is anyone here pretty familiar with the way the Tacos library
implemented Partial Forms? If so, could you reality check me on how I
*think* the implementation was managed? I've done a fair amount of AJAX
stuff, but that was all with my own servlets and my own javascript, so I'm
familiar with the core concepts, but I'm a bit fuzzy on how exactly the
tacos components implemented them.
So, is this the proper model:
1) A Partial Form is posted. The javascript takes the contents of the
form, builds and encoded POST string, and calls it.
2) Tapestry catches the POST and redirects it to the appropriate
listener.
3) Tapestry listener implements POST.
4) Tapestry rebuilds *entire page* on server.
5) Tapestry returns entire page.
6) Javascript recognizes POST has completed.
7) Javascript parses result string.
8) Javascript plucks out any divs that are on the list of divs to be
updated.
9) Javascript replaces current document's version of that div with the
div that came out of the response.
As you can tell from the bolding, I'm concerned about step 4. Unless I'm
mistaken (which wouldn't be the first time), this particular AJAX
implementation isn't going to save me anything on page render time because
even if I'm only updating a small div in the middle of the form, Tapestry
still has to render the entire form and return it. So the only thing I'm
really saving on is the "screen flicker" associated with a complete redraw.
In terms of server side resources and network resources, I'm still A)
building the whole form and B) sending the whole form.
Am I wrong here? Is there some alternative approach to make tacos just
render (and respond with) the divs its interested in?
--- Pat
