Which alv-grid for own build

Question

Hi,
how and what kind of ALV i must use to build own ALV-List (columns with content i create).
For understanding:
to test it, i will counting something and show that in a new column (counter). But i dont find any way to do that. In one thread i read "cl_salv_table", in the next "cl_gui_alv_grid", then "fieldcatalog" and so on... i'm confused at the moment.
the only answer i need is:
1. what are the correct way... cl_gui_alv_grid, cl_salv_table, ... i will find a way to create a list like my own conceivabilities. not a classic one.. a new one.
Thats my code, but i dont know how i can create any new column (with a name i give and content i create [anywhere in code - till now not in snipped])
*&---------------------------------------------------------------------*
*& Report  ZMW_TESTOBJECTS2
*&
*&---------------------------------------------------------------------*
*&
*&
*&---------------------------------------------------------------------*
REPORT  zmw_testobjects2.
*&---------------------------------------------------------------------*
*& Global Declarations
*&---------------------------------------------------------------------*
TABLES: tabelle1,
        tabelle2,
        tabelle3.
* SELECTION-SCREEN                                                     *
SELECTION-SCREEN BEGIN OF BLOCK choices WITH FRAME.
PARAMETERS:
  l_field1 TYPE tabelle1-field1 OBLIGATORY,
  l_field2 TYPE tabelle2-field2 OBLIGATORY,
  l_field3 TYPE tabelle2-field3,
  l_field4 TYPE tabelle1-field4.
SELECTION-SCREEN END OF BLOCK choices.
*&---------------------------------------------------------------------*
*& Class Test Definition
*&---------------------------------------------------------------------*
CLASS test_class DEFINITION.
  PUBLIC SECTION.
    CLASS-METHODS: read_data,
                   fill_list.
  PRIVATE SECTION.
      TYPES: BEGIN OF struc_out_table1,
              field3 LIKE tabelle2-field3,
              field2 LIKE tabelle2-field2,
              field4 LIKE tabelle1-field4,
              field1 LIKE tabelle1-field1,
              field5 LIKE tabelle3-field5,
             END OF struc_out_table1.
    CLASS-DATA: it_out_table1   TYPE TABLE OF   struc_out_table1,
                ctl_salv_list   TYPE REF TO     cl_salv_table,
                ctl_salv_exc    TYPE REF TO     cx_salv_msg.
ENDCLASS.                    "test_class DEFINITION
*&---------------------------------------------------------------------*
*& Class Test Implementation
*&---------------------------------------------------------------------*
CLASS test_class IMPLEMENTATION.
*&---------------------------------------------------------------------*
*& Method read_data
*&---------------------------------------------------------------------*
  METHOD read_data.
    SELECT tabelle2~field2 tabelle2~field3 tabelle1~field1
       FROM tabelle2
          INNER JOIN tabelle1
            ON tabelle2~field3 = tabelle1~field3
            INTO CORRESPONDING FIELDS OF TABLE it_out_table1
              WHERE    tabelle1~field1 = l_field1
              AND      tabelle2~field2 = l_field2
              ORDER BY tabelle2~field3.
        CALL METHOD fill_list.
  ENDMETHOD.                    "read_data
*&---------------------------------------------------------------------*
*& Method fill_list
*&---------------------------------------------------------------------*
  METHOD fill_list.
    TRY.
      cl_salv_table=>factory(
        EXPORTING
          list_display = 'X'
        IMPORTING
          r_salv_table = ctl_salv_list
        CHANGING
          t_table      = it_out_table1
                  ctl_salv_list->display( ).
    CATCH cx_salv_msg INTO ctl_salv_exc.
      MESSAGE ctl_salv_exc TYPE 'I'
        DISPLAY LIKE 'E'.
    ENDTRY.
  ENDMETHOD.
ENDCLASS.                    "test_class IMPLEMENTATION
START-OF-SELECTION.
  test_class=>read_data( ).

Answer 1

Hi Marc,
You may use any of the above ALVs. Either should suit your requirements.
If I understand you correctly, you want to add an extra column in the displayed ALV grid/table. The values to be displayed in this additional column are not present in the Tables, but you want to calculate the values at runtime.
As you know already, the ALV needs a field-catalog  [FC] and  a table storing the data [IT].
Please do the following.
1. Create a local structure (LS) having the relevant database tables and your new columns. You can't use a DB structure if all the columns you want to show are not present in the DB structure.
2. Create a internal table with line type LS. This table (IT) has to be passed to the ALV.
3. Manually fill the columns in the IT as you need it.
If you are using FM 'REUSE_ALV_FIELDCATALOG_MERGE' to build your field-catalog, your problem is solved here.  Instead of the DB structure, you have to pass your own structure to this FM.
However, if you are using manual creation of the FC, you'll need to append additional rows to the FC manually.
Cheers!
Abhinava