How do you get the values (not the selected values but the possible values) of a selectitems tag from SSJS ?

 

Background

I have a dialog with several comboboxes, the values for which are set in a selectitems tag by javascript functions. The function always returns at least one default value ('Select Target')

e.g.

                    <xp:panel rendered="#{javascript:showTarget()}">
                        <xp:comboBox id="cbTarget">
                            <xp:selectItems value="#{javascript:getTargetOptions()}" id="siTarget" />
                            <xp:this.validators><xp:validateExpression expression="#{javascript:validateTarget()}" message="Please select target"/></xp:this.validators>
                        </xp:comboBox>
                    </xp:panel>                       

I only want to show the combobox if there are values other than the default 'Select Target'. At present the function showTarget() calls the same function that generates the selectItems getTargetOptions(), checks the results to determine whether to show the panel.

 

As it's inefficient to call the getTargetOptions() function twice I would prefer to call the function once, and then have the showTarget() function check the values of the combobox component to determine whether to render the combobox.

 

function showTarget() {

    var ComboBox = getComponent('cbTarget')

    var ChildrenList:java.util.ListIterator = ComboBox.getChildren().listIterator()
    while (ChildrenList.hasNext()) {
        var Child = ChildrenList.next()
        if (typeof(Child) == 'com.ibm.xsp.component.UISelectItemsEx') {
            //Have handle to SelectItems but unable to get any further
            //as unable to identify which function to use to access the individual select items

            //I suspect it's Child.getValue() but it's an object of a type I don't know and 

            //designer autohelp doesn't recognise either
            //typeof(Child.getValue()) = '[Ljavax.faces.model.SelectItem;'
        }
    }
}