Function
GtkTreeIterCompareFunc
Declaration
int
(* GtkTreeIterCompareFunc) (
GtkTreeModel* model,
GtkTreeIter* a,
GtkTreeIter* b,
gpointer user_data
)
Description [src]
A GtkTreeIterCompareFunc should return a negative integer, zero, or a positive
integer if a sorts before b, a sorts with b, or a sorts after b
respectively.
If two iters compare as equal, their order in the sorted model
is undefined. In order to ensure that the GtkTreeSortable behaves as
expected, the GtkTreeIterCompareFunc must define a partial order on
the model, i.e. it must be reflexive, antisymmetric and transitive.
For example, if model is a product catalogue, then a compare function
for the “price” column could be one which returns
price_of(a) - price_of(b).
Parameters
model-
Type:
GtkTreeModelThe
GtkTreeModelthe comparison is within.The data is owned by the caller of the function. a-
Type:
GtkTreeIterA
GtkTreeIterinmodel.The data is owned by the caller of the function. b-
Type:
GtkTreeIterAnother
GtkTreeIterinmodel.The data is owned by the caller of the function. user_data-
Type:
gpointerData passed when the compare func is assigned e.g. by
gtk_tree_sortable_set_sort_func()The argument can be NULL.The data is owned by the caller of the function.