CATREFRESHDRAW Name
CATREFRESHDRAW
Purpose
The purpose of this utility routine is to allow objects lower down in a DRAW
hierarchy to request DRAW events from object higher in the hierarchy. For example,
if an IMGAXIS object needed to refresh itself, it would need to call the DRAW
method on the DRAWWIDGET at the top of the graphics hierarchy. It couldn't just
draw itself. There may be one or more objects between the object that requests a
DRAW and the one that needs to perform the DRAW.
If the "STOP_AT" keyword is not specified, the redraw request will
progress to the top of the object hierarchy. If the final object is
a DRAWWIDGET, the DRAW method is called with the ERASE_WINDOW keyword set.
Author
FANNING SOFTWARE CONSULTING
1645 Sheely Drive
Fort Collins, CO 80526 USA
Phone: 970-221-0438
E-mail: davidf@dfanning.com Category
Programming.
Calling Sequence
CatRefreshDraw, object, STOP_AT=thisObjectClass
Inputs
object: The object which requires the refresh. This must be sub-
classed from 'CATATOM'. Keywords
NOERASE: If the object whose draw method is called is a DRAWWIDGET object,
then the draw method is called with the ERASE_WINDOW keyword set.
By setting this NOERASE keyword, you will prevent the ERASE_WINDOW
keyword from being set.
TARGET_WINDOW: The target display window object. Sent to the DRAW method of any
DRAWWIDGET that is found. Ignored in any other case.
REQUESTER: Set this optional keyword equal the the object reference of the object
requesting the DRAW.
STOP_AT: Set this keyword to the object class name at
which the search is to stop.
For example, if "DrawWidget" is specified, the draw will
propogate up the hierarchy until a DRAWWIDGET object
(or a sub-class) is encountered. This object will have its
DRAW method called just before this routine completes.
Notes
Note that any PIXMAPWIDGET encountered during traversal will be refreshed.
Modification History
Written by: David W. Fanning, 21 July 2003.
Added TARGET_WINDOW keyword, 11 July 2005. DWF.