Hi Pradeep,
We can enable & disable the input fields in GET_DATA method.First fetch the value of Radio Button through radio button group event.
CASE IO_EVENT->MV_EVENT_ID.
When 'RADIO_BUTTON_EVENT'.
field-SYMBOLS: <fs_field> like line of CT_FIELD_USAGE.
IF <CONDITION>.
loop at CT_FIELD_USAGE ASSIGNING <FS_FIELD>.
case <FS_FIELD>-NAME.
when 'FIELD_NAME'.
<FS_FIELD>-READ_ONLY = 'X'.
ENDCASE.
ENDIF.
CV_FIELD_USAGE_CHANGED = abap_true.
Regards,
Harsha