XFA Specification
New XFA Template Features
970
Data Binding
Complex binding, version 2.4
Data binding can update properties other than
value
via an explicit reference to the Data DOM or to a
web service. Almost any property can be updated this way at bind time, for example a caption can be
copied from a data value.
See “Bind to Properties (Step 5)” on page 181.
Conditional binding, version 2.4
Data binding to the
value
property of a container via an explicit data reference can be conditional upon
the value of the data. This is accomplished via an extension to the grammar for SOM expressions.
See
“Selecting a Subset of Sibling Nodes” on page 95.
Dynamic forms, version 2.1
These are forms that change in structure in accordance with the data. See
“Static Forms Versus Dynamic
Forms” on page 259
Repeating subforms, version 2.1
In XFA 2.0, when it was desired to repeat the same subform multiple times, it was necessary to re-declare
the subform once for each instance. In XFA 2.1 a repeating subform can be declared just once along with
properties that control how many times it repeats. See
“Forms with Repeated Fields or Subforms” on
page 200
Explicit data references, version 2.1
The automatic data-binding logic can now be overridden on a per-field basis. The field can be forced to
bind to an arbitrary node in the Data DOM. See
“Explicit Data References” on page 176
for detailed
information.
Subform sets, version 2.1
Subforms can now be grouped under a controlling object called a subform set. The subform set declares
the logical relationship of the subforms, for example, that they are mutually exclusive. The logical
relationships supported correspond closely to the relationships supported by common schema
languages. See
“Subform Set” on page 275
Record processing, version 2.1
Data can now optionally be processed a record at a time. In this mode only a logical record of data is
loaded into memory at any one time. Processing in record mode limits consumption of memory and CPU
cycles. It also limits the scope of data binding to the current record in most cases.
See “Creating, Updating,
and Unloading a Basic XFA Data DOM” on page 113.
Global fields, version 2.1
A field can now be declared global. A field declared this way can bind to certain data outside the current
record. Globals were not required in XFA 2.0 because it did not support record processing. See
“The Bind
Element” on page 157
for detailed information.
Note that in every case XFA 2.1 data binding is backwards-compatible with XFA 2.0 templates and data.
The default behavior is always the same as the XFA 2.0 behavior.