gtk:tree-sortable-set-sort-func (sortable column func)

sortable -- a gtk:tree-sortable object
column -- an integer with the sort column ID to set the function for
func -- a gtk:tree-iter-compare-func callback function

Sets the comparison function used when sorting to be func. If the current sort column ID of sortable is the same as column, then the model will sort using this function. The gtk:tree-sortable implementation is deprecated since 4.10. Please do not use it in newly written code.