Object Services - How to loop at a table ' osreftab ' ?

Question

Hi Object Services Gurus,
I'm try to transform a table selected via object services (transaction service) to a table with type VRM_VALUES (the one necessary to fill selection screen listbox parameters).
So, i have a table with type 'osreftab' and i need to loop it accessing the attributes of its lines (which i just know at runtime). How can i proceed with this? Below is what i'm trying..
* (This is a method of a global class which pretends to transform a variable 'osreftab' into a variable 'vrm_values').
DATA: l_wa_value TYPE VRM_VALUE,
           l_i_values TYPE VRM_VALUES.
DATA: l_o_tax_code TYPE OSREF.
* im_tax_codes type is osreftab
LOOP AT im_tax_codes INTO l_o_tax_code.
*l_wa_value-KEY = l_o_tax_code->?
*l_wa_value-text = l_o_tax_code->?
  APPEND l_wa_value TO l_i_values.
ENDLOOP.

Answer 1

You can't cast b/w data reference which l_tax is and object reference which l_o_tax_code is.
osref is a generic object type and you store a reference to some object in it, right? So the question is: what kind of object you store there? Please note - this must be an object reference , not data reference .
i.e
"here goes some class
class zcl_spfli definition.
endclass.
class zcl_spfli implementation.
endclass.
"here is an OBJECT REFERENCE for it, (so I refer to a class) i.e persistent object to table SPFLI
data oref_spfli type ref to zcl_spfli.
"but here I have a DATA REFERENCE (so I refer to some data object) i.e DDIC structure SPFLI
data dref_spfli type ref to spfli.
So my OSREF can hold only oref_spfli but it not intended for dref_spfli . That's why you get this syntax error. Once you have stored reference to zcl_spfli in osref then you will be able to dereference it and access this object's attributes.
data: osref type osref.
create object osref_spfli.
osref = osref_spfli.
"now osref holds reference to object, you can deference it
oref_spfli ?= osref.
osref_spfli->some_attribute = ....
OSREFTAB is just a table whose line is of type OSREF (so can hold multiple object references - one in each line).
Regards
Marcin