*&---------------------------------------------------------------------*
*& This Code snippet shows how to
*&   Create Dynamic Internal Table
*&   Dynamic Selection of data
*&   Accessing Dynamic data selection
*&   Displaying Dynamic internal table in ALV
*&---------------------------------------------------------------------*
report zdynamic_itab.
*
* Exisiting Table type
TYPES: BEGIN OF ty_kstar,
       kstar TYPE kstar,
       END   OF ty_kstar.
*
* Dynamic Table creation
DATA: lo_struct   TYPE REF TO cl_abap_structdescr,
      lo_element  TYPE REF TO cl_abap_elemdescr,
      lo_new_type TYPE REF TO cl_abap_structdescr,
      lo_new_tab  TYPE REF TO cl_abap_tabledescr,
      lo_data     TYPE REF TO data,
      lt_comp     TYPE cl_abap_structdescr=>component_table,
      lt_tot_comp TYPE cl_abap_structdescr=>component_table,
      la_comp     LIKE LINE OF lt_comp,
      lf_months   TYPE monat,
      lf_run_mon  TYPE monat.
*
* Dynamic Selection fields
TYPES: BEGIN OF ty_fields,
       field TYPE char30,
       END   OF ty_fields.
*
DATA:  lt_fields TYPE STANDARD TABLE OF ty_fields,
       la_fields TYPE ty_fields.
*
* field symbols to access the dynamic table
FIELD-SYMBOLS: <f_tab>   TYPE ANY TABLE,
               <f_line>  TYPE ANY,
               <f_field> TYPE ANY.
*
* Selection Screen
PARAMETERS: p_mon_fr TYPE monat,
            p_mon_to TYPE monat.
*
START-OF-SELECTION.
*
*$*$*...............Dynamic Internal Table........................*$*$*
* 1. Getting Compoents from existing type
  lo_struct ?= cl_abap_typedescr=>describe_by_name( 'TY_KSTAR' ).
  lt_comp  = lo_struct->get_components( ).
  APPEND LINES OF lt_comp TO lt_tot_comp.
*
* 2. Adding required fields based on the single data element
* Determining Number of fields
  lf_months = ( p_mon_to - p_mon_fr ) + 1.
  lf_run_mon = p_mon_fr.
*
  DO lf_months TIMES.
*
*   Element Description
    lo_element ?= cl_abap_elemdescr=>describe_by_name( 'WTGXXX' ).
*
*   Field name
    CONCATENATE 'WTG0' lf_run_mon INTO la_comp-name.
*
*   Field type
    la_comp-type = cl_abap_elemdescr=>get_p(
                      p_length   = lo_element->length
                      p_decimals = lo_element->decimals ).
*
*   Filling the component table
    APPEND la_comp TO lt_tot_comp.
    CLEAR: la_comp.
*
    lf_run_mon = lf_run_mon + 1.
  ENDDO.
*
* 3. Create a New Type
  lo_new_type = cl_abap_structdescr=>create( lt_tot_comp ).
*
* 4. New Table type
  lo_new_tab = cl_abap_tabledescr=>create(
                  p_line_type  = lo_new_type
                  p_table_kind = cl_abap_tabledescr=>tablekind_std
                  p_unique     = abap_false ).
*
* 5. data to handle the new table type
  CREATE DATA lo_data TYPE HANDLE lo_new_tab.
*
* 6. New internal table in the fieldsymbols
  ASSIGN lo_data->* TO <f_tab>.
*
*$*$*...............Dynamic Selection.............................*$*$*
* Filling up the table for the Selection fields of Select Query
  LOOP AT lt_tot_comp INTO la_comp.
    la_fields-field = la_comp-name.
    APPEND la_fields TO lt_fields.
    CLEAR: la_comp, la_fields.
  ENDLOOP.
*
* Selecting data
  SELECT (lt_fields)
         INTO  TABLE <f_tab>
         FROM  cosp
         UP TO 10 ROWS.
*
*$*$*...............Accessing dynamic table.......................*$*$*
  LOOP AT <f_tab> ASSIGNING <f_line>.
    ASSIGN COMPONENT 'WTG004' OF STRUCTURE <f_line> TO <f_field>.
    <f_field> = '100.00'.
  ENDLOOP.
*
*
*$*$*...............Displaying using SALV model...................*$*$*
*
  DATA: lo_alv TYPE REF TO cl_salv_table.
*
  TRY.
      cl_salv_table=>factory(
        EXPORTING
          list_display = abap_false
        IMPORTING
          r_salv_table = lo_alv
        CHANGING
          t_table      = <f_tab> ).
    CATCH cx_salv_msg .
  ENDTRY.
*
  lo_alv->display( ).