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Chapter 4, Exchanging Data Between an External Application

and a Basic XFA Form

XFA Specification

Basic Data Binding to Produce the XFA Form DOM

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Transparent Nodes

In data binding, as in SOM expressions, certain template nodes (such as nameless subforms) are

transparent. This means that data binding, like SOM expression resolution, behaves as though the

transparent nodes were removed and their children adopted by the transparent node's parent. For

example, if a nameless subform is wrapped around a field, the field still binds to the same data value in the

same place in the data hierarchy. The data binding process does copy the transparent node into the Form

DOM, so the Form DOM echoes the hierarchy of the Template DOM, but the form node which is a copy of a

transparent node remains unbound.

The following example shows the registration template with a nameless subform wrapping around the

address information:

</subform>

</template>

The following figure shows what results when this template is bound to the original data. All of the data

bindings are still direct matches because the nameless subform is transparent.