| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: standard-object
Returns or sets with setf the value of the on-sort-predicate event-handler
property of a dialog-item
. The value may be a
function name or function object, which determines the ordering of
items in a list-view-column
, grid-column
, or
outline
control. The value may also be nil
to
indicate that the control is not sortable (using its built-in sorting
functionality). When the value is a function, the function should
accept two arguments and return true when the first value should
precede the second (as with the predicate argument to cl:sort).
For a list-view-column
, where the sorted
values are always strings, the default value is string-lessp (for a case-insensitive
alphanumeric sort). For a grid-column
or outline
, the default is nil
because the sortable values are arbitrary Lisp
objects, and so there is no possible general default predicate that
would not cons strings in many cases. For these objects, a custom
on-sort-predicate
must be supplied in order to use the built-in sorting behavior.
The on-sort-predicate function (if any)
is used when calling sort-grid on a grid-widget
, when calling add-outline-item-value
(without an explicit position argument) or
replace-outline-item-value on an
outline
control, when calling list-view-sort, (setf
sort-column) or (setf sort-reverse) on a list-view
control
(which happens internally when clicking a list-view
column header).
See cg-events.htm for information about event handling in Common Graphics.
Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 8.1 page.
Created 2010.1.21.
| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |