I want to use chart module(c3 lib) of drupal 8 to show a chart of user count for different roles using views. E.g.
Role Name Total user a 5 b 10 c 13
I achieved above table using aggregation in views. I followed this guideline to create a chart but when I create chart attachment and add it to parent, the value of child replace the value in the parent chart.It should merge. Any help would be appreciable.