Gantt chart does not work when task with id "0" is added

Gantt
#1

encountered some weird behaviour. when i have a task with id “0” the component does not seem to handle this.

I had a very big hierarchical dataset, the reported error was “Error: Invalid tasks tree. Cyclic reference has been detected on task Location 0”
Changing that specific id solved the issue.

#2

Hello,
In Gantt, id = 0 is reserved as the default value for gantt.config.root_id, which defines the virtual root of the task tree.

If you assign a task id: 0, and its parent is also 0 (the default root), the task becomes its own parent — causing a cyclic reference error:

Error: Invalid tasks tree. Cyclic reference has been detected on task 0

You can either:

  • Avoid using id = 0;
  • Or change the root ID:
gantt.config.root_id = "root";

Here is an example: DHTMLX Snippet Tool