XForms Essentials

Name

insert

Synopsis

This action works within a node-set, by constructing new nodes based on a template. The immediate problem with this approach is that if there are no nodes present in the repeating set (as can happen after invoking the delete action), what template can be used to copy from? The answer depends on the way instance data is constructed in XForms: as a separate in-memory representation. The initial instance data, as it appears inside the instance element in the containing document (or in an external linked file) doesn’t change as the instance data changes through all the various interactions defined by XForms. Thus, the initial instance data is defined as the source of the template to be copied, even though it makes for some awkward terminology to explain how it works.

The main attributes that control the operation of this element are:

single-node binding attributes

These attribute or attributes select a node-set, which matches the node-set selected by a repeat set.

at

This attribute selects the location within the node-set where the inserted element node will appear. Generally, it is one of three possibilities:

• To insert a new repeat item at the beginning, at="1“.

• To insert a new repeat item at the end, at="last( )“.

• To insert a new repeat item at the current index, at="index('id_of_repeat')" (where id_of_repeat represents the IDREF of the <repeat> element).

position

This attribute is required, and must be either "before" or "after“—where to insert the new node relative ...