How to get alignment in treeview

[Hariyanto <xhonghar gmail com>]

I using gtktreeview with 3 column to display some data. 
I set alignment Center in header column with gtk_tree_view_column_set_alignment().
And I set alignment data with g_object_set (renderer, "xalign", 1.0, NULL); 

How I get alignment from data ?
I try using gtk_tree_view_column_get_alignment(), but i can only alignment from header.

thx. 
Hariyanto.