An icon is a small image representing the application when the application’s frame is in a
closed, or iconiﬁed, state. The ICON package is very small. It is subclassed from the WINDOW
package because it is a window that displays graphics and accepts input. The only attributes
that you can set in the ICON package specify the image to display in the window and the
geometry of the image. Other important attributes that an icon can have (such as width,
height, label, and font) are attributes of the generic class.
2.4.5 Nonvisual Objects
There are several nonvisual objects that cannot be represented on the screen but are sub-
classed from the Generic Object:
CMS Colormap segments (cms) are objects that are associated with windows
which provide their color speciﬁcations. Cms objects may be shared by
DROP_SITE_ITEM The drop site item is a rectangle that is an area used for dragging an
object and dropping data associated with the object onto the drop site’s
FONT The font package allows the programmer to request fonts of varying
attributes such as font family and style. Fonts can be accessed by name,
size or scaling.
SCREEN This object describes the visual and other characteristics of the physical
screen. This object is separate from the Xlib SCREEN object.
SELECTION This package allows clients to transfer data between applications.
SERVER This package interacts with the X server. The window-server is the pro-
gram that does the drawing to the screen and receives the user’s input.
The server also maintains font information and user-conﬁgurable
resources, which can be set for speciﬁc applications.
These objects are closely tied with the X Window System, and they are manipulated by mak-
ing requests to set or get attributes from X.
34 XView Programming Manual