GtkTreeSortable
<!-- ##### SECTION Short_Description ##### -->
-
+The interface for sortable models used by GtkTreeView
<!-- ##### SECTION Long_Description ##### -->
<para>
-
+#GtkTreeSortable is an interface to be implemented by tree models which
+support sorting. The #GtkTreeView uses the methods provided by this interface
+to sort the model.
</para>
<!-- ##### SECTION See_Also ##### -->
<para>
-
+#GtkTreeModel, #GtkTreeView
</para>
+<!-- ##### SECTION Stability_Level ##### -->
+
+
+<!-- ##### SECTION Image ##### -->
+
+
<!-- ##### STRUCT GtkTreeSortable ##### -->
<para>
</para>
+<!-- ##### SIGNAL GtkTreeSortable::sort-column-changed ##### -->
+<para>
+
+</para>
+
+@treesortable: the object which received the signal.
+
<!-- ##### STRUCT GtkTreeSortableIface ##### -->
<para>
<!-- ##### USER_FUNCTION GtkTreeIterCompareFunc ##### -->
<para>
-
+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.
+</para>
+<para>
+For example, if @model is a product catalogue, then a compare function
+for the "price" column could be one which returns
+<literal>price_of(@a) - price_of(@b)</literal>.
</para>
-@model:
-@a:
-@b:
-@user_data:
-@Returns:
+@model: The #GtkTreeModel the comparison is within
+@a: A #GtkTreeIter in @model
+@b: Another #GtkTreeIter in @model
+@user_data: Data passed when the compare func is assigned e.g. by
+gtk_tree_sortable_set_sort_func()
+@Returns: a negative integer, zero or a positive integer depending on whether
+ @a sorts before, with or after @b
<!-- ##### FUNCTION gtk_tree_sortable_sort_column_changed ##### -->