The TreeGrid component mentioned in the doc exists in Vaadin Framework 8.1, which release is currently in beta.
The TreeGrid add-on is built for Vaadin 7 and it doesn’t have this feature.
Try upgrading to 8.1 to use the feature. Upgrading from 8 is very simple, while upgrading from 7 may require some more work, but you can use the compatibility package for a smoother transition.
but I want to know if the version 7 will implement the method addExpandListener because i need a method like addItemClickListener to know when user click on node in a treegrid.