| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: dialog-item
Use of this function is deprecated. Common Graphics now always internally calls this function on all Microsoft widgets, and so there is never a need for an application to call it. Calling this function will now simply do nothing.
Performs what might be called "MS subclassing" on the window of dialog-item. This has nothing to do with CLOS classes, but rather causes lisp to intercept all low-level messages that are sent to widget windows and are normally handled within the Windows operating system where these widgets are implemented. All low-level Windows events for dialog-item will be passed to the pc:control-procedure generic function. In addition, the keypress and mouse-click events will call an event method for the dialog-item's window and that event.
You need to call subclass-widget only if you want to
handle these low-level Windows events that are usually handled by
MS-Windows internally. For example, when a user types a new value into
an (single-line) editable-text
widget, you normally
know only what the new string and the old string are; if you want to
know what actual key was pressed, then you will need to call subclass-widget and then
write an event method on the window to handle the keypress event. Or
you may want to intercept a mouse click on a widget even when its
value is not
changed by the click.
If subclass-widget is called on a
widget that is already subclassed, no action is taken and nil
is returned, otherwise t
is returned.
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 |