Virtualvfunc_Get the item at position. If position is greater than the number of
items in list, null is returned.
null is never returned for an index that is smaller than the length
of the list. See g_list_model_get_n_items().
The same GObject.Object instance may not appear more than once in a Gio.ListModel.
the position of the item to fetch
Virtualvfunc_Gets the type of the items in list.
All items returned from g_list_model_get_item() are of the type
returned by this function, or a subtype, or if the type is an
interface, they are an implementation of that interface.
The item type of a Gio.ListModel can not change during the life of the model.
Virtualvfunc_Gets the number of items in list.
Depending on the model implementation, calling this function may be
less efficient than iterating the list with increasing values for
position until g_list_model_get_item() returns null.
Interface for implementing ListModel. Contains only the virtual methods that need to be implemented.