easy alv report just for display

REPORT ZTEST_002.

TABLES:MARA.

SELECT-OPTIONS: S_MATNR FOR MARA-MATNR.
DATA:  G_ALV TYPE REF TO CL_SALV_TABLE.

TYPES: BEGIN OF T_MARA,
            MATNR TYPE MARA-MATNR,
            NORMT TYPE MARA-NORMT,
            GROES TYPE MARA-GROES,
       END OF T_MARA.

DATA:  I_MARA TYPE STANDARD TABLE OF T_MARA,
       W_MARA LIKE LINE OF I_MARA.

SELECT MATNR NORMT GROES FROM MARA INTO TABLE I_MARA WHERE MATNR IN S_MATNR.

TRY.
    CALL METHOD CL_SALV_TABLE=>FACTORY
      IMPORTING
        R_SALV_TABLE = G_ALV
      CHANGING
        T_TABLE      = I_MARA.
  CATCH CX_SALV_MSG.
ENDTRY.
G_ALV->DISPLAY(  ).