How to create a generic TYPES?

Question

hello!
what i try to do is following
eg:
when i call my function the user has the possibility to check the flag "show_button = 'X', and exports a table
when this flag is checked i want to display an icon in the first row of this table, so i need to extend the table structure which i import and add another attribute.
what i actually tried to achieve is this (but this is not working of course)
function
import:
      i_outtab type standard table.
field-symbols:
      <itab> type standard table.
assign i_outtab to <itab>.
TYPES: begin of mytyp.
   types: i_bt type iconname.
  INCLUDE STRUCTURE <itab>
TYPES: end of mytyp.
and then i create a table with the type mytyp (which is not working, but i shows what i try to do)
so is there a way to do this genericly?

Answer 1

You can do that using the ABAP Run Time Type Services.
Example:
I have a function module Y_TEST with one Importing Parameter:
*"  IMPORTING
*"     REFERENCE(IP_IT_DATA) TYPE  ANY TABLE
I have no idea about the table-structure and I want to add a field X_SELECTED of type XFELD to the end of the table to display it using CL_SALV_TABLE or something - this is how I do it:
FUNCTION y_test.
*"  IMPORTING
*"     REFERENCE(IP_IT_DATA) TYPE  ANY TABLE
  DATA:
    gr_tabtype TYPE REF TO cl_abap_tabledescr,
    gr_struc   TYPE REF TO cl_abap_structdescr,
    lr_itab    TYPE REF TO data,
    it_component TYPE cl_abap_structdescr=>component_table,
    wa_component LIKE LINE OF it_component.
  FIELD-SYMBOLS:
    <wa> TYPE ANY.
* Reading 1st line of itab and getting structure ->
  LOOP AT ip_it_data ASSIGNING <wa>.
    gr_struc ?= cl_abap_typedescr=>describe_by_data( <wa> ).
    EXIT.
  ENDLOOP. "ip_it_data
* Getting all components ->
  CHECK gr_struc IS BOUND.
  it_component = gr_struc->get_components( ).
* Adding new field (X_SELECTED) to Component-Table ->
  wa_component-name = 'X_SELECTED'.
  wa_component-type ?= cl_abap_typedescr=>describe_by_name( 'XFELD ').
  INSERT wa_component INTO TABLE it_component.
* Creating new structure-ref ->
  CLEAR gr_struc.
      CALL METHOD cl_abap_structdescr=>create
        EXPORTING
          p_components = it_component
        RECEIVING
          p_result     = gr_struc.
* Creating new table-ref ->
      CALL METHOD cl_abap_tabledescr=>create
        EXPORTING
          p_line_type  = gr_struc
        RECEIVING
          p_result     = gr_tabtype.
* Creating itab with our table-ref ->
  CREATE DATA lr_itab TYPE HANDLE gr_tabtype.
ENDFUNCTION.
Hope that helped ...