ABAP_to_the_Future

11
ABAP2XLSX
EXPORTING
io_worksheet = core_object " Worksheet
ip_column = ip_column " Cell Column
ip_row = ip_row " Cell Row
ip_current_max = ip_current_max " Current maximum Width
RECEIVING
ep_width = ep_width ). " New Width
ENDMETHOD.
Listing 11.34 Coding an Overwrite Method
You will notice that in Listing 11.34 you cannot refer to the class you are enhancing
by using the me keyword to refer to the class instance; instead, you have to use
the term CORE_OBJECT. This is because when the ov erwrite method is called you
aren’t inside the main ZCL_EXCEL_WORKSHEET class; you’re inside a generated class
called LCL_ZEI_EXCEL_EXTENSIONS. which has an instance of the real class called
CORE_OBJECT passed into it upon creation.
11.3.2 Creating a Reusable Custom Framework
When looking at the code samples throughout this chapter, you may have noticed
that often it takes a large amount of code to achieve each function; the conditional
formatting code is a case inpoint. Despite this, every time you find yourself wanting
to cut and paste a large chunk of co de out of one program and into another
one and then change one or two input valu es, you should take a leaf out of the
Spice Girls’ book and stop right now. Obviously, this applies to programming as
a whole: not just ABAP2XLSX, not just SAP, but all code everywhere. However,
I’m talking about ABAP2XLSX specifically here, and although it’s good to work
out how to do each task, once you have that worked out it’s time to hide the complexity
in your own custom method of some sort of generic ABAP2XLSX Z custom
class.
For this example, assume there is such a class in the system, and (for example) the
code in Listing 11.33 is encapsulated in a method in that reusable Z class. It is the
same for emailing or downloading a spreadsheet: In each case, you have about 20
lines of code with just one value varying for each report, so it’s best to have a
reusable Z method with all the code that never changes in it, taking the variable
data as input parameters.
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