Gets the logical @sort_column_id that the model sorts on when this column is selected for sorting.
See [method@Gtk.TreeViewColumn.set_sort_column_id].
the current @sort_column_id for this column, or -1 if this column can’t be used for sorting
See Implementation
Gets the logical @sort_column_id that the model sorts on when this column is selected for sorting.
See [method@Gtk.TreeViewColumn.set_sort_column_id].