| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: grid-widget
This method returns the name of the grid-drawing-pane
class that a
grid-widget
should instantiate for the drawing area of the grid. This method may
be useful in unusual cases where the widget-windows of a grid-widget
need to be subclassed.
Every dialog-item instance that is placed onto a parent window has an
associated widget-window
or lisp-widget-window
instance for the actual window that appears on the screen for the
dialog-item. In atypical cases where it is necessary to subclass a
widget-window
class along with a dialog-item class, a widget-device method is written to
tell the dialog-item subclass which widget-window
or lisp-widget-window
subclass to
instantiate automatically.
A grid-widget
is a special case in that it has an additional associated
widget-window. This window is a child of the main widget-window and
contains the entire grid body except for the border at the outside
edge of the grid. If this window needs to be subclassed as well, then
a grid-drawing-pane-class-for-grid
method should be written to tell the grid-widget subclass which
grid-drawing-pane
subclass to use,
just as the widget-device method tells it which
grid-top-pane
subclass to use. The method should take a grid-widget
instance as its only
argument and return the name of a subclass of grid-drawing-pane
.
There should be no need to subclass a grid-widget's widget-window
classes in typical applications that add cell-click, cell-key-down, and draw-cell methods to
handle events and drawing on a grid. But if that API is not sufficient
and it is necessary to write methods for a grid on lower-level generic
functions such as mouse-left-down or virtual-key-down, then
the grid-drawing-pane
class may be
subclassed to provide a class on which to specialize these methods.
The function grid-drawing-pane (called on the
main widget-window of a grid-widget
) returns the
grid-drawing-pane just as the function window (called on a dialog-item)
returns the main widget-window.
Here is the default method:
(defmethod grid-drawing-pane-class-for-grid (grid-widget) (declare (ignore grid-widget)) 'grid-drawing-pane)
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 |