lightning:treeGrid Row level actions

A lightning:treeGrid component displays hierarchical data in a table. Its appearance resembles lightning:datatable, with the exception that each row can be expanded to reveal a nested group of items. Rows that contain nested data display a chevron icon to denote that they can be expanded or collapsed. In this example, I will show how to use the row-level actions on the tree grid as shown below.

Apex Class 

Lightning Component