| Allegro CL version 6.2 Unrevised from 6.1 | |||||||||
A non-instantiable class that can be mixed with the grid-column class to
create grid columns whose cells act like combo-box controls. Each cell in
the column will implement the pseudo-control if the row of that cell
is an instance of a grid-row subclass that mixes in the
widget-row-mixin class.
Instances of this may use real combo-boxes or simulations
(such as pop-up menus). Which is used depends on the value of the
use-real-combo-box property.
When the user clicks on the down-arrow gadget displayed in the cell,
the cell-click
method provided by this mixin displays a list of choices and calls
write-cell-value
with the new choice if the user selects one. When the user clicks
anywhere else in the cell, other properties of the grid-column determine whether this
gesture displays the list of choices, initiates type-in, or does
nothing. The user may alternately press the spacebar to emulate
clicking on the down-arrow or the enter key to emulate clicking
elsewhere in the cell.
The typable property of the column may be used to indicate whether the user may optionally type in a new value directly. When the typable property is true, the edit-start-trigger and edit-end-trigger properties of the column may be used to determine what gesture the user must make to initiate and complete the typing in of a new value for the cell.
The range-reader property should be used to determine the set of choices that will be presented in each cell's drop-down list. The on-print property may be used to convert the choices to strings to be displayed in the cell's drop-down list (though the column's data-read-converter is called to convert the cell's actual value to the string displayed in the cell).
The click-must-be-on-gadget property
may be used to determine where the user must click within the cell to
display the list of choices when the typable property is nil. (When typable is true, the user must
always click on the drop-down arrow to show the list of choices, since
clicking elsewhere in the cell initiates type-in instead.)
Copyright (c) 1998-2002, Franz Inc. Oakland, CA., USA. All rights reserved.
Documentation for Allegro CL version 6.2. This page was not revised from the 6.1 page.
Created 2002.2.26.
| Allegro CL version 6.2 Unrevised from 6.1 | |||||||||