The term “relevance” refers to the algorithms used by XpressDox to determine whether the control to capture a data element in the interview should even appear in the interview.
In the simplest case, the fillpoint
«CompanyRegistrationDate» will cause a simple text control to appear in the interview for data element CompanyRegistrationDate.
«If(PartyType = ‘Company’)»
will only result in that text control for the data element appearing in the interview when the value of the PartyType data element is ‘Company’.
This is an example of Conditional Relevance.
This refers to a set of features in XpressDox, all related to interview generation, which enables the template author to provide a set of interview layout instructions not only for one template but for all templates in a suite of templates. This is covered in the Interview Layout article.
How this works is that there are many data capture commands which in essence say “only if the data element in this command is needed in the running template, then include the relevant control for it in the interview.”
These commands include Caption, Heading, Footing, Tab and all the Choose… commands which appear in the Data Capture category in the Command Editor.
Then, expanding the earlier example about CompanyRegistrationDate, suppose the command
appears somewhere at the top of a template (or, probably, inside a template included via the IncludeCodeTemplate command), but in fact no other fillpoint occurs in the template which requires the value of that CompanyRegistrationDate data element. In that case, no date picker (or any other control) will appear on the interview for that data element.
Whereas even a command like
«If(RenderAsNumeric(CompanyRegistrationDate)»«RenderAsNumeric(IncrementDate(‘today’,-1,’y’)))» would cause the data element CompanyRegistrationDate to be “usage relevant” and the date picker will then appear in the interview.
Note that this feature is available only in Version 4 and later of XpressDox.