Hiding a Portlet Manager

There are several methods for hiding a portlet manager.

A portlet manager won't display if there are no portlets assigned to it to display or if the assigned portlets have no data.

In the case of the portlet columns, if the portlet manager is empty, then it is also useful to have the surrounding block elements disappear too, so that you don't get a wide blank margin on your page. For this reason, the columns containing the portlet managers in the main_template are wrapped around with slots. Hiding the portlet managers is, therefore, a matter or manipulating these slots. There are various techniques:

Defining an empty slot

Use the following in a content view template to ensure that the right hand column is removed:

• <metal:column_one fill-slot="column_one_slot" />

Using the sl and sr global variables

These are set as conditions on the slots; they check the respective portlet managers for content and, if they are empty, evaluate to false. You can override these in the template itself.

Using show_portlets option

show_portlets=false can be passed as an option to a template to set both sl and sr to false. To see this in action, have a look at

• CMFPlone/skins/plone_templates/standard_error_message.py and
• CMFPlone/browser/ploneview.py