ABAP_to_the_Future

Computer science departments have always considered “user interface”
research to be sissy work.
—Nicholas Negroponte, founder and director of the Massachusetts
Institute of Technology’s Media Laboratory
10 ALV SALV Reporting Framework
To start Part III, which focuses on the us er interface (UI) layer, this chapter
explains how to make best use of the SALV framework to code reports that run
inside the SAP GUI. Although the SAP GUI is not particularly futuristic (quite the
opposite), the SALV framework within the SAP GUI replaced the traditional ALV
reporting framework and is still widely unfamiliar to many ABAP developers. The
good news is that the SALV framework is a technology that old-school ABAPers
find easy to get their heads around; it could be compared to Henry Ford’s “faster
horse.”
A lot of programmers hate writing reports.They feel they are boring compared to
cutting-edge new programs, and if they do have to write a report they want the
pain of doing so over as quickly as possible. The first and most obvious way of
doing this is to have a template program: When a new report is needed, you copy
the template and then insert the report-spe cific tables and retrieval logic. In the
days of procedural programming, you could isolate all repetitive ALV code in an
INCLUDE program. You could have an INCLUDE program for all the data declarations,
such as the definitions for the field catalog and sort catalog tables and so on,
and another INCLUDE for the routines, such as adding a new line to the field catalog—that
is, the routines that would alwa ys be identical if you created each program
normally. As time went on, you also started to see ALV robot types of programs
on the Internet that you could download. You ran the program and said
what your internal table would look like, and the whole program was generated
for you using the ability of SAP to use a program to create another program.
You’d think that would be the ideal so lution—but generated code tends to be
lengthy due to (for example) not encapsulating repetitive code in a routine.
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