CHAPTER 8
592
Interactive Features
KEY
TYPE
VALUE
V
boolean
boolean
(Optional) The initial visibility of the field in the user interface. Default
value:
true
.
(Optional) A flag indicating whether the PDF viewer application should
provide support for editing the field value. Default value:
false
.
E
A
collection sort dictionary
identifies the fields that are used to sort items in the
collection. The type of sorting depends on the type of data:
•
Text strings are ordered lexically from smaller to larger, if ascending order is
specified.
•
Numbers are ordered numerically from smaller to larger, if ascending order is
specified.
•
Dates are ordered from oldest to newest, if ascending order is specified.
TABLE 8.9 Entries in a collection sort dictionary
KEY
TYPE
VALUE
Type
name
name or
array
(Optional) The type of PDF object that this dictionary describes; if present,
must be
CollectionSort
for a collection sort dictionary.
(Required) The name or names of fields that the PDF viewer application uses
to sort the items in the collection. If the value is a name, it identifies a field
described in the parent collection dictionary.
If the value is an array, each element of the array is a name that identifies a
field described in the parent collection dictionary. The array form is used to
allow additional fields to contribute to the sort, where each additional field
is used to break ties. More specifically, if multiple collection item dictionar-
ies have the same value for the first field named in the array, the values for
successive fields named in the array are used for sorting, until a unique or-
der is determined or until the named fields are exhausted.
S
A
boolean or
array
(Optional) Specifies whether the items in the collection are sorted in ascend-
ing order. If the array form is used, each element of the array is a boolean
value that specifies whether the entry at the same index in the
S
array is sort-
ed in ascending order.
Default value:
true
.