Correct process for updating CRM Z fields from ERP Z field.

Question

I currently have an accounts block with a field (Region) which has a drop-down list box containing values, plus another field containing the description/name of the region. Based on other fields within this same block I need to replace the Region and its description with a single value which should be sourced from an ERP Z table, or joined Z tables if I include the description as well.
I believe that I know how to change the attributes of the Region field using the AET, although I can't see anything which displays or allows me to displable the drop-down list of values, although I'm sure I've seen a video demonstrating the AET being used to create a list of lookup values.
Anyway, what I need to do is to change the Region field, making it and its description field Read-only, remove the list of values option so there's no drop-down list box against the Region field, and also update this field from an ERP Z field. Can this all be done using either the AET or EEWB, or is there some code required to be manually entered, and if so, what transactions need to be used to do this?.
Any help would be much appreciated.
Jason

Answer 1

MIcha,
With regards to youe 9 steps that gave.
I am looking at component BP_ADDR and view BP_ADDR/StandardAddress. However, there are no enhancements shown when I click on the [Enhance Component] button. So I assume that I need to create an enhancement in order to change the code. Does this enhancement create am implementation or does it create replacement code?. The reason for asking this is that the code shown against the View_controller->Content->Content_Nodes->STANDARDADDRESS->Attributes->STRUCT.REGION->GET_V_REGION method is as follows::
METHOD GET_V_REGION.
  DATA:
    lv_fieldname            TYPE name_komp,
    lt_fieldname_additional TYPE crmt_attr_name_tab.
  lv_fieldname = 'COUNTRY'.                                 "#EC NOTEXT
  INSERT lv_fieldname INTO TABLE lt_fieldname_additional.
  lv_fieldname = 'COUNTRY_TEXT'.                            "#EC NOTEXT
  INSERT lv_fieldname INTO TABLE lt_fieldname_additional.
  lv_fieldname = 'REGION_TEXT'.                             "#EC NOTEXT
  INSERT lv_fieldname INTO TABLE lt_fieldname_additional.
  CALL METHOD cl_crm_uiu_bp_cust_get=>GET_VHELP_FOR_REGION_VATTR
    EXPORTING
      iv_index                = iv_index
      it_fieldname_additional = lt_fieldname_additional
    RECEIVING
      rv_valuehelp_descriptor = rv_valuehelp_descriptor
    EXCEPTIONS
      OTHERS                  = 0.
ENDMETHOD.
The above call gets the value helps and if I replace this code how can I also ensure that the value-help pull down icon does not appear next to the Region field, as all I'm attempting to do here is replace the code. In other words where do I update the screen to say that this field is no longer a value help field?. I wondered if this code actuallypoints the pull-down icon next to the Region field, although I suspect all it does is physically display the list of values and allows you to select one.
So, I need to determine how I can create an enhancement. I've just been trying different things in the BSP_WD_CMPWB tranx but have not found out yet how this is achieved, although I think this is achieved via the creation of a new View set, but am not 100% sure.
Jason