ABAP_to_the_Future

Designing a Report Interface 10.2
Figure 10.10 User Command Received Event Parameters
However, the more common situation is that the user double-clicks a specific cell
in the report. In this case, parameters ED_ROW and ED_COLUMN will be filled with the
coordinates of the cell that was clicked on and ED_USER_COMMAND will be filled with
a system generated constant; it’s the wittily named &IC1, which is the value the
SAP system automatically sets when a user double-clicks something. In this case,
the row number and column number become vitally important so that the part of
the program that deals with the user action can know exactly what the user wants
dealt with (e.g., which sales order—or monster—to display).
Note that this is not about responding to what the user has done; this is just about
broadcasting the fact that the user ha s done something. The problem of how to
respond to that something is the responsibility of another part of the program.
The view is ideally placed to recogniz e such an event, because only the view
knows exactly what the screen looks like and what technology is being used to
interact with the user. Once the view has raised such an event, its work here is
done.
As mentioned earlier, it’s not the job of the view to respond to any commands the
user makes; its job is to pass the inform ation about what the user just did on to
the parts of the program best suited to deciding what the proper response should
be. Half the articles on MV C say the view should talk directly to the model, and
half say the view and the model should know nothing about each other and only
communicate via the controller. In the latter case, it becomes easy to replace the
view without affecting the model (e.g., when a new user interface technology
comes along) and likewise to use the same view for various similar models (e.g.,
you have lots of different models for approving various things, like leave requests
and purchase orders, and you want them all to have the same look and feel, so
you use the same view each time).
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