ABAP_to_the_Future

10
ALV SALV Reporting Framework
Note
Section 10.3 and Section 10.4 of this chapter discusses souping up this method to make
it do “impossible” things, but for now you’ve got the basics.
10.2.3 Report Flow Step 3: Making Application-Specific Changes
(Specific)
You now come to the part of the progra m that will vary wi th each and every
report: the application-specif ic changes. For incredibly simple reports that only
display a read-only representation of every column of an internal table, you may
well have to do nothing here; however, it’slikely that sooner or later the business
users are going to demand something extr a. You achieve this by calling one or
more methods to do things like optimi ze the column widths, change various
aspects of the columns of data, or sort and subtotal the data in a specific way.
Since you are pretty much always going to have to make application-specific
changes, there needs to be a method to do this. Good news; there is! There is a
definition of an APPLICATION_SPECIFIC_CHANGES method in the interface that is
an abstract method in the concrete ZCL_BC_VIEW_SALV_TABLE class; that is, the
method is always redefined by the calling program. Therefore, in the calling program,
you will have code like that in Listing 10.8.
In this code, first the column widths ar e optimized to make them look pretty.
Then, the column definitions are changed in various ways to satisfy various common
business requirements. Next, the code specifies how the data is to be sorted.
Finally, there’s a bucket load of error handling.
CLASS lcl_view IMPLEMENTATION.
METHOD application_specific_changes.
* Local Variables
DATA: lo_error TYPE REF TO cx_salv_msg,
lo_not_found TYPE REF TO cx_salv_not_found,
lo_data_error TYPE REF TO cx_salv_data_error,
ls_message TYPE bal_s_msg.
TRY.
lo_view->optimise_column_width( ).
lo_view->set_column_attributes( :
id_field_name = 'MANDT'
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