| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: grid-column
Returns a function that returns whether each of the grid cells in a
particular column of a grid-widget
is currently selected, or else returns
nil
to determine the selection status in
other ways (see cell-selected). The selected-reader function
is a property of a particular grid-column
, and is called once for
each grid-row
that intersects that column, to determine the selected status of the
cell at the intersection of that row and column. The function should
take one argument, which is the data-object of the grid-row
. If the cell
is currently considered to be selected, then the function should
return true, and otherwise it should return nil
. When selected, a grid cell is drawn in special
colors, and the application may treat it in some special way.
This property value may be specified as either a function name symbol
(which would be more debuggable), or a function object (which may be
slightly faster, though probably insignificantly), or nil
if this facility is not used. The default value
is nil
.
An application does not call the selected-reader function; it
supplies the selected-reader function by calling
(setf selected-reader) or by passing
the :selected-reader initarg when calling make-instance to create a grid-column
. The specified
function is then called automatically by the system as needed.
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 |