Dynamic Annotations (Part 2)

• By Joshua Milligan
• Posted in All, Tips and Tricks
• On June 1, 2013
• 5 Comments.

Edit – This post describes one approach. But, it turns out, there is an easier way: Dynamic Annotations (Part 3)

Part 1 described how to implement dynamic annotations in Tableau using a copy of a measure as a dual axis.  However, there were some limitations to that approach.  The biggest limitation is that you won’t be able to use the dual axis for anything else.

Here is a dashboard with a dual axis combo chart view that makes use of dynamic annotations.

 

This solution is very similar to the one proposed in Part 1.  However, instead of using a dual axis, I’m using the Measure Names / Measure Values.  With this approach, I can have as many copies of the measure for the marks I want to annotate as I want.  In that way, I can have multiple “sets” of annotations.

Here are the steps:

1. Create a parameter to control which set of annotations is shown.
   
   Tip: Use an integer type for performance and ease of coding.  You can change the “Display As” value for user-friendliness.
2. For every field that will define a mark for which you will use dynamic annotations, create a calculated copy.  Create a copy for each “set” of annotations. Here is an example of the calculated copies of the Sales measure.  Note that the field only has a value when the corresponding parameter is selected.  Otherwise it evaluates to NULL.

Field Name	Calculation
Sales (Annotation Set 1)	IF [Annotation] = 1 THEN [Sales] END
Sales (Annotation Set 2)	IF [Annotation] = 2 THEN [Sales] END
Sales (Annotation Set 3)	IF [Annotation] = 3 THEN [Sales] END
Sales (Annotation Set 4)	IF [Annotation] = 4 THEN [Sales] END

1. Once you have a view using the original field to define the marks as you want, replace that field with the [Measure Values] field.  Then make sure each calculated copy is placed on the Measure Values shelf.
   Tip: You will need to add [Measure Names] to the Level of Detail if you want to connect a line.
2. Cycle through selecting each parameter value.  Add mark annotations as desired for each parameter selection.

 

That’s it!  You now have annotations that dynamically change based on end-user interaction!