ABAP_to_the_Future

Using BOPF to Write a DYNPRO-Style Program 8.2
Figure 8.14 Displaying a Determination in Transaction BOB
In this case, you want to the do the PB O trick (filling out derived fields before
showing them to the user)—you can tell because the Determination Pattern
field has been set to Fill Transient Attributes of Persistent Nodes —and fill
some text fields straight after you have the database fields.
After you finish the wizard, the next task is to actually code ZCL_D_FILL_MONSTER-
HEADER_TEXT. Looking at the generated class, the first thing to notice is that the /
BOBF/IF_FRW_DETERMINATION interface has been added to the new class. The interface
for determinations has the following three methods you can implement (the
first two are optional):
왘 CHECK_DELTA
This corresponds to the DYNPRO concept of ON-INPUT. This method works out
what fields have been changed; this is important, because usually only some
fields will need to trigge r determination if they ha ve been changed. In the
DYNPRO framework, this was part of the UI logic, but really this is the job of
the model.
왘 CHECK
This is very subtly different; this time, the method looks at the new content of
the changed fields. This is important, because sometimes you need to work out
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