specifies a control model which supports both binding to an external value supplier,
and to an external validator.
There are two methods how the value which is represented by a control model
can interact with other components (well, except the trivial ones accessible
by using ::com::sun::star::beans::XPropertySet):
binding the value to an external component via ::com::sun::star::form::binding::XBindableValue
specifies support for binding the control value to an external component
If a value binding is established at the control model (by using
::com::sun::star::form::binding::XBindableValue::setValueBinding with a non-NULL
binding), this binding is analyzed for validation support. If it is present (read: if the
binding also supports the XValidator interface), the binding is also
established as validator, as if it has been passed to XValidatable::setValidator.
If, while this binding is active (in both its roles as value binding and validator),
an attempt is made to establish another validator, this is blocked with raising a
::com::sun::star::util::VetoException upon calling XValidatable::setValidator.
