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Allegro CL version 10.0
Unrevised from 9.0 to 10.0.
9.0 version

font-reader

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) 1998-2019, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 9.0 page.
Created 2015.5.21.

ToCDocOverviewCGDocRelNotesFAQIndexPermutedIndex
Allegro CL version 10.0
Unrevised from 9.0 to 10.0.
9.0 version