The SelectItemsIndexConverter automatically converts between the index of the select item value and the select item value itself based on its position in the associated select items for the component for which conversion is taking place.

This converter has the following advantages over SelectItemsConverter:

• No need to rely on toString() method of the object.
• No need to extend the SelectItemsConverter when toString() method of the object cannot be used.
• No need to expose the object's unique key if that's a problem.

This converter has the following disadvantage over SelectItemsConverter:

• The "Validation Error: value is not valid" will never occur anymore for the case that the available select items has incompatibly changed during the postback due to a developer's mistake. The developer should make absolutely sure that exactly the same list is preserved on postback (e.g. by making it a property of a view scoped or broader scoped bean).

This converter is available by converter ID omnifaces.SelectItemsIndexConverter. Basic usage example:

 <h:selectOneMenu value="#{bean.selectedEntity}" converter="omnifaces.SelectItemsIndexConverter">
   <f:selectItems value="#{bean.availableEntities}" var="entity"
     itemValue="#{entity}" itemLabel="#{entity.someProperty}" />
 </h:selectOneMenu>