Hi Abdul,
1, Add STYLES type LVC_T_STYL to your Data table(which you want to display in grid)
2. In PBO ,while filling data into your Data table ,Fill STYLES field as per your requirement.
Example:
LOOP GT_FCAT INTO LWA_FCAT."GT_FCAT is your data table
IF LWA_FCAT-KEY_COLUMN IS NOT INITIAL. " Here we are checking the condition . So, your cell is editable for new entries
lwa_style-fieldname = 'KEY_COLUMN'.
lwa_style-style = cl_gui_alv_grid=>mc_style_disabled.
INSERT lwa_style INTO TABLE LWA_FCAT-styles.
ENDIF.
APPEND LWA_FCAT TO GT_FCAT.
ENDLOOP.
2. In your controls_display
ls_layout-edit = abap_true.
ls_layout-stylefname = 'STYLES'.
ref_grid->SET_TABLE_FOR_FIRST_DISPLAY
EXPORTING
IS_LAYOUT = ls_layout
...............
Regards,
Shiva