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Allegro CL version 8.2
Unrevised from 8.1 to 8.2.
8.1 version

data-read-converter

Arguments: grid-column

Returns the function that converts the programmatic value returned by this grid-column's data-reader function into the actual value that is displayed in a grid cell. This is similar to the on-print property of many controls. Typically the function returns a formatted string, but may return other sorts of values for grid-columns that represent data with non-strings (such as the bar-chart in the employee grid example). The employee grid example can be found on the Examples tab of the Navigator.

The function should take a single argument, which is an arbitrary data-object attribute value.

For example, in the employee grid example, the Department column's data-reader is employee-department, which is simply the reader method for the department slot of an employee instance. When called on an employee instance, this function returns a symbol like :marketing. This symbol is fine for representing the department programmatically, but to display it nicely in a grid cell, the Department grid-column has the data-read-converter "capitalize-if-symbol", which is a function that takes the symbol :marketing and returns the string "Marketing" to display in the grid cell.

A special case is that the values that appear in the drop-down list of a combo-box-column-mixin cell are formatted by the on-print function of the grid-column even though the value appearing in the grid cell itself is formatted by the column's data-read-converter function as with other grid cells. To use the same formatting in both places, specify the same function for each of these properties.

NOTE: Your application does not call the data-read-converter function; it supplies the data-read-converter function which is then called automatically by the system as needed.

data-read-converter is a property of the grid-column and row-header-column classes.


Copyright (c) 1998-2012, Franz Inc. Oakland, CA., USA. All rights reserved.
Documentation for Allegro CL version 8.2. This page was not revised from the 8.1 page.
Created 2010.1.21.

ToCDocOverviewCGDocRelNotesFAQIndexPermutedIndex
Allegro CL version 8.2
Unrevised from 8.1 to 8.2.
8.1 version