XFA Specification
Chapter 2, Template Features for Designing Static Forms
Form Structural Building Blocks
31
subform or its contents; it only affects how much height the layout processor reserves upon the page for
the subform. Widths work the other way around. The width of a
contentArea
is not a physical constraint;
the content placed into the
contentArea
can extend to the right of the
contentArea
. However the
width of a subform may be a physical constraint; text may wrap when it reaches the right or left edge of
the subform. (This asymmetry arises from the fact that XFA does not currently support languages such as
Chinese that flow vertically with lines stacked horizontally. Probably any future version of XFA that
supports such languages will expand the repertoire of
contentArea
elements to include splitting by
width, and of subforms to include wrapping by height.)
The following table summarizes the types of layout elements:
Type
physical
layout
content
Subtype
N/A
structural
Description
physical display elements or regions
thereof
logical and some physical
relationships between layout
elements
elements visibly presented upon the
display
Element
pageSet, pageArea, contentArea
subform, subformSet, area,
exclGroup, field, draw
text, image, line, arc, rectangle,
barcode, push button, checkbox,
radio button, choice list, text edit
widget, date edit widget, time edit
widget, password edit widget, image
picker widget, signature widget
displayable
“Layout Objects” on page 955
layout element.
Content Elements
A content element is a type of XFA template element that houses datatyped pcdata (text) or graphic
elements (lines and images). Such pcdata or graphic elements may be defined as default data or
un-changeable data in the content element.
Content elements may be used to house information that is interactive or non-interactive, as follows:
●
●
Interactive data, which is enclosed in
field
and exclusion group (
exclGroup
Non-interactive data, which is enclosed in
draw
Most containers have a notion of a value. This value can be used in calculations and may be persisted
when the form's variable content is saved. For
draw
and field containers, the value is the container's
content, available through the
value
subelement.
The following diagram illustrates the relationship between elements in a content element.