User interface services define how users may interact with an application. Depending on
the capabilities required by users and the applications, these interfaces may include the
following:
- Graphical client-server services that define the relationships between client and
server processes operating graphical user interface displays, usually within a network. In
this case, the program that controls each display unit is a server process, while
independent user programs are client processes that request display services from the
server.
- Display objects services that define characteristics of display elements such as
color, shape, size, movement, graphics context, user preferences, font management and
interactions among display elements.
- Window management services that define how windows are created, moved, stored,
retrieved, removed and related to each other.
- Dialogue support services translate the data entered for display to that which is
actually displayed on the screen (e.g., cursor movements, keyboard data entry, external
data entry devices).
- Printing services support output of text and/or graphical data, including any
filtering or format conversion necessary. Printing services may include the ability to
print all or part of a document, to print and collate more than one copy, to select the
size and orientation of output, to choose print resolution, colors and graphical behavior,
to specify fonts and other characteristics.
- Computer-based training and on-line help services provide an integrated training
environment on user workstations. Training is available on an as-needed basis for any
application available in the environment. Electronic messages are provided at the stroke
of a key from anywhere within the application. This includes tutorial training on the
application in use and the availability of off-line, on-site interactive training.
- Character-based services, which deal with support for non-graphical terminals.
Character-based services include support for terminal type-independent control of display
attributes, cursor motions, programmable keys, audible signals and other functions.
The services associated with a window system include the visual display of information
on a screen that contains one or more windows or panels, support for pointing to an object
on the screen using a pointing device such as a mouse or touch-screen, and the
manipulation of a set of objects on the screen through the pointing device or through
keyboard entry. Other user interfaces included are industrial controls and virtual reality
devices.
Copyright © The Open Group, 1998