[Zope] How to create a trigger?

[Fredrick Rybarczyk - LUB NetLab]

Hi,
Sorry for this newbie question. Hope anyone has the time to help me out.

I would like to do something like this within a dtml document that has a
property:
int my_property = 0

<dtml-if "my_property==0">
<a href= .. ???>press this to show some content</a>
<dtml-else>
<a href= .. ???>press this to hide some content</a>
<dtml-/if>

... a bit down in the document
<dtml-if "my_property>0">
show some content
<dtml-/if>

...or in plain words. I want to set the value of a property ( or
variable if that would serve me better ) whenever I click on a link. Can
someone please show how to do it?
Thanks

--
==========================================
Fredrick Rybarczyk
Research Engineer
NetLab, Lund University