Display Conditions are used in HTML Blocks and Field Blocks to determine when the content defined in an HTML/Field Block is displayed.
A display condition is used to conditionally display a block of HTML or dynamically retrieved content. It is a TALES expression; for information on TALES, see for example http://wiki.zope.org/ZPT/TALESSpecification13 and http://plone.org/documentation/tutorial/zpt/advanced-usage.
There are several predefined variables that can be used as starting points in the TALES expressions:
- portal
- action
- edition
- record
- request
- session
In addition, there are some predefined numerical variables:
- onsite_edition_count
- onsite_edition_goal
- onsite_edition_progress
- onsite_action_count
- onsite_action_goal
- onsite_action_progress
For detailed help see the documentation on Conditional Blocks.