xref: /aoo4110/main/offapi/com/sun/star/form/binding/BindableDataAwareControlModel.idl (revision b1cdbd2c)

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#ifndef __com_sun_star_form_binding_BindableDataAwareControlModel_idl__
#define __com_sun_star_form_binding_BindableDataAwareControlModel_idl__

#ifndef __com_sun_star_form_DataAwareControlModel_idl__
#include <com/sun/star/form/DataAwareControlModel.idl>
#endif

#ifndef __com_sun_star_form_binding_BindableControlModel_idl__
#include <com/sun/star/form/binding/BindableControlModel.idl>
#endif

//=============================================================================

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

//=============================================================================

/** is a specialization of the <type scope="com::sun::star::form">DataAwareControlModel</type>
    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
    <type scope="com::sun::star::form::component">TextField</type>, this would be the
    <member scope="com::sun::star::awt">UnoControlEditModel::Text</member> property of the base
    service. Similarily, a <type scope="com::sun::star::form::component">CheckBox</type> has
    a property <member scope="com::sun::star::awt">UnoControlCheckBoxModel::State</member>, which
    reflects the current check state.</p>

    <p>Usual <type scope="com::sun::star::form">DataAwareControlModel</type>s can be bound to
    a column of a <type scope="com::sun::star::form::component">DataForm</type>, and exchange
    their content with such a column.<br/>
    In particular, when the <type scope="com::sun::star::form::component">DataForm</type>
    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
    (<member scope="com::sun::star::form">XBoundComponent::commit</member>), then the actual
    data of the control model is written into the associated
    <type scope="com::sun::star::form::component">DataForm</type> column.</p>

    <p><type>BindableDataAwareControlModel</type>'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
    <type scope="com::sun::star::form::component">DataForm</type> column).</p>

    <p>For this, they provide the <type>XBindableValue</type> 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 (<type scope="com::sun::star::form">XLoadable</type>).
            </li>
            <li><b>Immediacy</b><br/>
                When a <type>BindableDataAwareControlModel</type> 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
                <type scope="com::sun::star::form">DataAwareControlModel</type>'s, where changes
                in the control model's value are only propagated to the bound column upon explicit
                request via <member scope="com::sun::star::form">XBoundComponent::commit</member>.<br/>
                Note that this restriction is inherited from the <type>BindableControlModel</type>.
            </li>
            <li><b>Cloning</b><br/>
                <type scope="com::sun::star::form">FormControlModel</type>s support cloning themself
                via the <type scope="com::sun::star::util">XCloneable</type> interface which they
                inherit from the <type scope="com::sun::star::awt">UnoControlModel</type> service.</br>
                When a <type>BindableDataAwareControlModel</type> 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 <type>BindableControlModel</type>.
            </li>
        </ul>
    </p>

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

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

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

//=============================================================================

}; }; }; }; };

#endif