CIFER®-MATLAB Interfaces: Development and ... - Cal Poly

3.2.1 Development Process
The most difficult aspect of developing the GUI was adjusting the look and feel to appeal to the
widest audience of potential users. The iterative method used for the command-line development
was employed for the GUI as well, with NASA engineers and programmers included during the
design process. Several initial concepts were sketched on paper before any code was written.
When ideas were put into code, the first programs were designed only around the layout of the
GUI, lacking any real functionality. This allowed reviewers a clear idea of what the finished
product might look like. Once the design for the layout was sufficiently refined, the functionality
was written into the code. As the functionality was based on the command-line interface, the
focus of the GUI development was the layout.
The GUI was largely built up around the command-line code that already could interface with
CIFER ® . Data entry in the GUI was largely handled by toggles and text fields. The error checking
from the command line was superseded by similar checks within the GUI to make its use closely
resemble the old CIFER ® interface. Appendix A shows the COMPOSITE screens from both the
old interface and the new GUI.
3.2.2 Modern Updates to the Original Interface
Perhaps the most visible change between the original interface and the new MATLAB GUI was
the added navigational features. CIFER ® was originally designed to run on VAX/VMS systems
and as a result, uses the keyboard function keys for navigation. There were menus that could be
accessed for navigation within each program; however they are not always intuitive in use. Thus
two primary navigation bars were added to the GUI interface. The left bar, found in Appendix A,
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