Gets the number of accessible children currently selected.
Note: callers should not rely on NULL or on a zero value for
indication of whether AtkSelectionIface is implemented, they should
use type checking/interface checking macros or the
atk_get_accessible_value() convenience method.
Gets the number of accessible children currently selected. Note: callers should not rely on NULL or on a zero value for indication of whether AtkSelectionIface is implemented, they should use type checking/interface checking macros or the atk_get_accessible_value() convenience method.