Chapter 4, Exchanging Data Between an External Application
and a Basic XFA Form
XFA Specification
Basic Data Binding to Produce the XFA Form DOM
171
Template
DOM
registration
Form DOM
registration
Data DOM
registration
first
first
“Jack”
last
“Spratt”
first
“Jack”
last
“Spratt”
last
apt
apt
“”
street
“99 Candlestick Lane”
city
“London”
country
“UK”
postalcode
“SW1”
apt
“”
street
“99 Candlestick Lane”
city
“London”
country
“UK”
postalcode
“SW1”
street
city
country
postalcode
Transparent node handling
Nameless fields are also transparent, unless they make explicit data references. Explicit data references are
explained below in
“Explicit Data References” on page 176.
Note that the transparency of nameless
subforms and fields is not arbitrary. Rather, because they are nameless, they cannot be referred to in the
normal way by SOM expressions. Hence they are also excluded from data binding. However like nameless
subforms they are still copied into the Form DOM where appropriate so that scripts and other XFA
subsystems can use them. (Because they are nameless the script has to refer to them via SOM expressions
using class names. For example the above nameless subform would be referred to as
$form.registration.#subform
.)
A subform can also be transparent even though it has a name. This happens when the subform’s
scope
property is set to
none
. Such a subform is treated like a nameless subform by the data binding process but
at the same time scripts can access the transparent subform by name.
Nodes representing
area
elements are also transparent to data binding, even when they are named.
There are also various nodes that are descended from subforms but do not participate in data binding