How can i build a gird which can show data in hierarchical tree, with a cus

Hello all,
1. i want to build a gird which can show data in hierarchical tree. 
2.Also except for the columns defined in the data structure, i need to add some custome colums for the gird. Ex.a cloumn contains some operation buttons for the row.

For 1, i find the tree-grid addon for this. https://vaadin.com/directory#!addon/vaadin-treegrid
For 2, i used to use GeneratedPropertyContainer for regural Grid to add custom columns, but failed to apply this in TreeGird.

 Any ideas for this? Ths.