Buttons missing on output screen (ALV using OOP)

Hi,

This is my first program on OOP, so I need little help. I have created a PF status (copied from SALV_TABLE_STANDARD). Few of the buttons that are present in my PF status are not getting displayed on ALV output screen, like select layout, save layout, info. My code is as below:

    go_alv->set_screen_status(

       EXPORTING

         report        =     sy-repid

         pfstatus      =     'CUSTOM_PF_STATUS'

         set_functions =     go_alv->c_functions_all ).

Regards,

Abhi