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module com {  module sun {  module star {  module form { module binding {


/** is a specialization of the com::sun::star::form::DataAwareControlModel
    which additionally supports binding to external value suppliers.

    <p>Control models usually have some kind of value property, which reflects the very current
    content of the controls associated with this model. For instance, for an
    com::sun::star::form::component::TextField, this would be the
    com::sun::star::awt::UnoControlEditModel::Text property of the base
    service. Similarly, a com::sun::star::form::component::CheckBox has
    a property com::sun::star::awt::UnoControlCheckBoxModel::State, which
    reflects the current check state.</p>

    <p>Usual com::sun::star::form::DataAwareControlModels can be bound to
    a column of a com::sun::star::form::component::DataForm, and exchange
    their content with such a column.<br/>
    In particular, when the com::sun::star::form::component::DataForm
    is moved to a different record, then the bound control model is updated with the value of
    it's column in this particular row.<br/>
    On the other hand, when any change in the control model (e.g. resulting from a user entering
    data in a control associated with the control model) is committed
    (com::sun::star::form::XBoundComponent::commit()), then the actual
    data of the control model is written into the associated
    com::sun::star::form::component::DataForm column.</p>

    <p>BindableDataAwareControlModel's additionally support an alternative value
    binding, which forces them to exchange their value with another foreign instance.
    In some sense, they are an abstraction of the data aware control models, which only
    support a specialized, hard-coded value binding (namely the binding to a
    com::sun::star::form::component::DataForm column).</p>

    <p>For this, they provide the XBindableValue interface which allows to
    set an external component to exchange the value with.</p>

    <p>The following rules apply when a data aware control model is bound to an external value binding:
        <ul><li><b>Priority</b><br/>
                External value bindings overrule any active SQL-column binding. If an external
                component is bound to a control model which currently has an active SQL binding,
                this SQL binding is suspended, until the external binding is revoked.
            </li>
            <li><b>Activation</b><br/>
                An external value binding becomes effective as soon as it is set. This is a
                difference to SQL bindings, which only are effective when the parent form
                of the control model is loaded (com::sun::star::form::XLoadable).
            </li>
            <li><b>Immediacy</b><br/>
                When a BindableDataAwareControlModel is bound to an external value,
                then every change in the control model's value is <em>immediately</em> reflected
                in the external binding. This is a difference to SQL bindings of most
                com::sun::star::form::DataAwareControlModel's, where changes
                in the control model's value are only propagated to the bound column upon explicit
                request via com::sun::star::form::XBoundComponent::commit().<br/>
                Note that this restriction is inherited from the BindableControlModel.
            </li>
            <li><b>Cloning</b><br/>
                com::sun::star::form::FormControlModels support cloning themselves
                via the com::sun::star::util::XCloneable interface which they
                inherit from the com::sun::star::awt::UnoControlModel service.<br>
                When a BindableDataAwareControlModel is cloned while it has an active
                external value binding, then the clone is also bound to the same binding instance.<br/>
                Note that this restriction is inherited from the BindableControlModel.
            </li>
        </ul>
    </p>

    <p>When a BindableDataAwareControlModel is being bound to an external value,
    using XBindableValue::setValueBinding(),
    then the control model (its value property, respectively) and the external value are
    initially synchronized by setting the external value (XValueBinding::getValue())
    at the control model.</p>

*/
service BindableDataAwareControlModel
{
    /** specifies the functionality for binding the control model to a
        column of an SQL com::sun::star::form::component::DataForm.
    */
    service com::sun::star::form::DataAwareControlModel;

    /** specifies the functionality for <em>alternatively</em> binding the control model
        to an external value.
    */
    service BindableControlModel;
};


}; }; }; }; };

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