| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: grid-column
Returns a function that returns the font to use when drawing each grid
cell of a a particular column, or else returns nil
to determine the font in other ways. This
function is called by the default cell-font method, which in
turn is typically called by a draw-cell method (including those
supplied by editable-text-column-mixin
and
other mixins). A font-reader may be nil
rather than a function if this facility is not
used. The default value is nil
.
The font-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 font 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 font
for a particular cell should be determined by the font-reader function, then it
should return the font to use, and otherwise it should return nil
.
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
.
An application does not call the font-reader function; it supplies the
font-reader function by calling (setf font-reader) or by passing the
:font-reader initarg when calling make-instance to create a grid-column
, and the specified
function is then called automatically by the system as needed.
See the grid-widget
class
for an overview of writing grid-widget code.
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 |