Identifies whether the field should be added to the default view.
xsf:xdYesNo
The viewable attribute is an optional attribute of the field element.
Values include "yes" and "no". The default value is "no".
The following is an example of the viewable attribute as it is used in the field element:
<xsf:listProperties>
<xsf:fields>
<xsf:field
type="xsd:date"
name="TravelDate"
columnName="TravelDate"
required="yes"
viewable="yes"
node="TravelReport/Header/travelDate"
aggregation="first"/>
</xsf:fields>
</xsf:listProperties>