Sean’s #WOW2024 challenge this week was to visualise the comparisons between different entities within a limited space, by using a Viz In Tooltip (VIT) to provide additional information on hover.

Building the Treemap

Add Sales to Size, Category to Colour and Sub-Category to Detail to create the basic tree map. Tableau will automatically define the layout based on the space available, and you can’t control this, so don’t worry if it doesn’t match the final output.

Move Sub-Category from Detail to Label and add Sales to Label too. Format Sales to to be $ at 0dp, then adjust the Label as required.

Crete a new field

Rank

RANK(SUM([Sales]))

Format the field so it is formatted to be a whole number with a suffix of .)

Convert to discrete and add to the Detail shelf. Adjust the table calculation and verify it is computing by both Category and Sub-Category – this ranks every cell from 1 to 17 based on the Sales.

Adjust the Tooltip to just show the Category, Sub-Category and Sales data.

Name the sheet TreeMap.

Building the bar chart (the VIT)

On a new sheet add Sub-Category to Rows and Sales to Columns. Sort by Sales descending. Add Category to Colour and adjust the opacity to around 30%. Manually widen each row.

Add Sales and Sub-Category to Label and adjust to get the correct layout and then align left middle.

Add Rank to Rows after Sub-Category. Hide the Sub-Category field (uncheck show header).

We need to identify a row that has been ‘selected’ by the user. For this we need a parameter

pSelectedRank

Integer parameter defaulted to 0

Show the parameter on the page. We need to indicate which row is selected.

Selected Rank Indicator

IF [Rank] = [pSelectedRank] THEN ‘●’ ELSE ” END

Add this field to Rows before Rank, then update the pSelectedRank parameter to a valid number, eg 5.

Hide field labels for rows, make the Selected Rank Indicator and Rank columns narrower. Adjust alignment of columns and increase the font size of the Selected Rank Indicator column.

Hide the Sales axis, remove all gridlines, zero lines and row & column dividers. Format the Row Axis Ruler to be a black line.

We only want a subset of the rows to show – those that are 2 below and 2 above the selected rank. Create a new field

Rank in Range

([Rank] >= [pSelectedRank]-2) AND ([Rank]<= [pSelectedRank]+2)

Add this to Rows in front of Sub-Category. The bar chart will split.

We only want to see the ‘True’ rows. You can do this in 2 ways.

1 – Click on the word True and select Keep Only from the dialog box displayed. This will add Rank in Range to the Filter shelf

or

2 – right click on the section with the False records and select Hide from the context menu. The rows associated to False will disappear but won’t actually be filtered out of the view (this is what I did)

Hide the Rank in Range column from showing (uncheck show header). Name this sheet VIT or similar.

On the TreeMap sheet, update the Tooltip to show the VIT worksheet (via Insert > Sheets). Adjust the code snipped inserted so the filter property = “” (ie no filters are passed and the complete viz is displayed).

If you test it from the worksheet, and still have the pSelectedRank set to 5, you should see the same set of bars regardless of which part of the TreeMap you hover on.

Applying the filter

Create a dashboard of the required size and add the TreeMap sheet. Set the viz to fit entire view. It’s likely it will now rearrange itself to (nearly) match the solution.

Add a parameter dashboard action to set the selected rank

Set Rank

On hover of the TreeMap sheet, set the pSelectedRank parameter by passing in the value from the Rank field aggregated to nothing. When the selection is cleared, set to 0.

Hovering over the dashboard should now update the display in the VIT to ‘focus’ on whichever Sub-Category has been selected on the TreeMap.

My published viz is here.

Happy vizzin’!

Donna