Understanding the Differences between Top-Level and Mixed-In Calendars in 25Live Publisher

Understanding the differences between top-level and mixed-in calendars is often a point of confusion for new users of 25Live Publisher.  This page explains the differences and when each is a more appropriate choice for more comprehensive and complex calendars.

Top-Level Calendar Description

A top-level calendar is composed of one or more sub-calendars. To create a top-level/sub-calendar framework, the sub-calendars all have to be published as sub-calendars in the feed publication process in 25Live. A top-level calendar can either be created as an empty container or it may be its own feed of events. 

Example: An Athletics calendar is one of the best examples of a potential top-level/sub-calendar framework. You could publish a feed of overarching Athletics division events that cross athletic teams as the top-level calendars. Then, you would publish individual sub-calendars for each of your intercollegiate athletic teams. Taken together, they represent the entirety of event scheduling for athletics and the relationship is represented by the top-level/sub-calendar framework.

Mixed-in Calendar Description

A mixed-in calendar is a calendar in which two or more calendars have been mixed together to create a more comprehensive calendar. 

Example: You might have a Major Events Calendar, a Student Life Calendar, and an Athletics Calendar that are each hosted on their own web page on your campus website. However, you want to create a more comprehensive calendar that contains the events on all three of those calendars. A mixed-in calendar combines the three calendar feeds together into one all-encompassing calendar. 

Mixed-in calendar feeds are considered siblings, or equals, so on the calendar list control they will all output aligned flush left.


Every calendar that you publish that is not specifically published as a sub-calendar is by default considered a top-level calendar. As such, we know that this top-level calendar has no specific relationship to any other calendars.  We can mix them together with other calendars but they stand alone.

How Top-Level and Mixed-In Calendars Differ

The biggest difference between a top-level calendar with sub-calendars and a simple mixed-in calendar is in presentation.  If you were to mix five calendars together in a mixed-in calendar and then look at the calendar list control, they will all print flush left as illustrated below.

Preview for calendar list

This presentation shows that the calendar contained in the mixed-in calendar are equals—or siblings—to each other. Each can stand alone on a separate web page on your campus's website but they have all been brought together in a mixed-in calendar to produce a more comprehensive campus calendar.

On the other hand, a top-level calendar will have all sub-calendars indented under it. 

Preview for calendar list with top-level and sub-calendars

Notice that in the case of each of the team sport sub-calendars falls under the SE Regional Athletics Calendar. Those sub-calendars could be published on a page devoted to each of those team sports separately, but this calendar shows that each of these sub-calendars make up the overarching athletics calendar.

Deciding Calendar Type to Use

Use a mixed-in calendar if:

Diagram: ...you want to create a comprehensive campus calendar, but you have a series of stand-alone feeds containing the events that would make up this calendar. Use a mixed-in calendar.

Use a top-level/sub-calendar construction if:

Diagram: ...you have a group of calendars that are related in some way and you want to represent that all these calendar make up a larger group calendar. Use a top-level/sub-calendar structure

The Main Pitfall of Mixing Calendar Feeds Together

There is always the danger of introducing doubled or tripled events to the mixed-in container, whether it be just a container for mix-ins or a top-level calendar for mix-in sub-calendars. Remember that each of the calendars being mixed-in has to include its own unique set of events. If any of the calendars look at the same set of events, when they are mixed together, you will start seeing the same event multiple times.

If you need a comprehensive calendar but some events have to show up on multiple stand-alone calendars (making them impossible to mix together without introducing a nasty duplication issue) you can simply build a special search for your comprehensive calendar that looks at all the calendar categories, resources, event types (however you are driving your calendar) and puts them all on one calendar feed. In that instance, it doesn't matter if you have multiple calendar categories on an event because the search is simply looking to see if it contains at least one. No duplicates will be created and you can use a Filter Control let users filter out events on the calendar.