Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

Compete to become Power BI Data Viz World Champion! First round ends August 18th. Get started.

Reply
TomHalpin
New Member

Help with custom Gantt from Madison Giammaria

Hi all!

I just came across an incredible looking Gantt from Madison Giammaria, built with the Deneb custom visualiser.

I have been trying to produce the core functionality using my own dataset but after countless attempts I am not able to produce the visual in Power BI. I have no idea what is causing this issue and I was hoping to leverage the expertise here.

 

Steps so far:

  • Downloaded the Deneb visual and latest json code from the github repo.
  • Mimicked the data, renamed my visual field names to match the expected value.
  • Tried changing my table names directly to see if that helped.
  • I have confirmed the data types and format match whats expected, by leveraging the example pbix provided.
  • I even replicated the "root" row to see if that helped.


Expected view:

Screenshot 2025-07-25 140650.png


My current view:

Screenshot 2025-07-25 135354.png
 
The Log errors show:

[Error] Cannot read properties of undefined (reading 'enabled')
[Error] Cannot read properties of null (reading 'length')

As you can see nothing is generating within the visual itself, and I am completely lost to what the problem is.
 
I appreciate any and all help. I know this would be extemely powerful to use for my use cases and would like to get it working.
 
Thank you,
Tom
1 ACCEPTED SOLUTION
TomHalpin
New Member

I found the issue. It was with my dataset. 
There were a couple empty dates which were causing some of my nodes on the hierarchy not to appear.

For anyone looking at this in the future, please ensure your entire tree is constructed properly.

View solution in original post

1 REPLY 1
TomHalpin
New Member

I found the issue. It was with my dataset. 
There were a couple empty dates which were causing some of my nodes on the hierarchy not to appear.

For anyone looking at this in the future, please ensure your entire tree is constructed properly.

Helpful resources

Announcements
August Power BI Update Carousel

Power BI Monthly Update - August 2025

Check out the August 2025 Power BI update to learn about new features.

August 2025 community update carousel

Fabric Community Update - August 2025

Find out what's new and trending in the Fabric community.

Top Solution Authors