[Zope] Re: yadtp (yet another dtml-tree problem)

[Dieter Maurer]

Werner Fabian writes:
 > I posted a problem that I am having with the dtml-tree tag in the 
 > zope@zope.org -list and in the "Zope-Forum", unluckily without getting an
 > y 
 > replies.
Please stay on the list!
 > ...

 > In the root folder there is a dtml-method called "show-tree" which does 
 > essentially this:
 > 
 > 
 > 	<dtml-tree expr="REQUEST.PARENTS[uplevel]"
 >                 	 skip_unauthorized=1
 >                 	 branches_expr="objectValues(['Folder','File','DTML 
 > Method','DTML Document'])">
 > 
 > 	<a href="<dtml-var absolute_url>">  <dtml-var title_or_id>
 > 	</a>
 > 
 > 	</dtml-tree>
 > 
 > 
 > This method is called from the "start folder" in essentially the followin
 > g way 
 > (index, e.g.):
 > 
 > 
 > 	<dtml-var standard_html_header>
 > 
 > 	<dtml-unless uplevel> <dtml-call "REQUEST.set('uplevel' , 0)"></dtml-u
 > nless>
 > 
 > 	<dtml-call "REQUEST.set('uplevel', _.int(uplevel))">
 > 	<dtml-call "REQUEST.set('uplevelp', uplevel+1)">
 > 
 > 	<a href="<dtml-var URL0>?uplevel=<dtml-var uplevelp>">Up</a>
 > 	<dtml-var show_tree>
 > 
 > 	<dtml-var standard_html_footer>
 > 
 > 
 > This works OK.
 > However, if - after having pushed up the tree-root by some levels - I wan
 > t to 
 > expand or collapse one of the branches by using the +/- - icons, the tree
 >  is 
 > displayed with "start folder" as tree-root again, instead of the folder w
 > here 
 > I tried to expand/collapse the branch.
 > 
 > How do I avoid this?
I am almost sure that *I* replied to your question in the list!

  Your problem is that the links for "expand/collapse" do not
  contain your "uplevel".

  Someone invented the "urlparam" attribute, but he did not think
  enough. In almost all cases, the parameter to extend the
  "expand/collapse" URL is not constant but an expression (as in your
  case).

  Your options:
  
    * search for the "urlparam_expr" patch someone donated
      to fix precisely this bad design. Unfortunately, the patch did not
      make it in the Zope core.

    * use a cookie to pass your "uplevel" around 

      This is not nice but you need not to patch Zope code.
      It is this, what I do in my DocFinder product (for
      a similar purpose to yours).


Dieter