PMS Template disabling header access and controlling pms dates

How to disable the header for the template so that user cant change:-
1. supervisor
2. validity date

goto se19
-> HRHAP00_ACC_HEADER (make a new badi base on this ie zhrap00_acc_header)
double click on GET_HEADER_ACCESS

S_HEADER_CUST_DISPLAY-APPRAISER = ' '. " to prevent user from changing the supervisor
S_HEADER_CUST_DISPLAY-VALIDITY_PERIOD = ' '. "to disable user from changing the dates

-> HRHAP00_DOC_DEF_DV (make a new badi base on this ie zHRHAP00_DOC_DEF_DV)
double click on DEFAULT_PERIOD

* changing default date to appraisal period
DATA: BEGDA TYPE DATUM,
ENDDA TYPE DATUM.
BEGDA = SY-DATUM.
BEGDA+4(4) = '0201'."february 01
ENDDA+4(4) = '0630'."june 30
ENDDA+0(4) = SY-DATUM+0(4) + 1. "adding current year

* set exporting data
S_PERIOD_VALIDITY-AP_START_DATE = BEGDA.
S_PERIOD_VALIDITY-AP_END_DATE = ENDDA.
NO_STANDARD_DEFAULTING = C_TRUE.

* note do remember you need to add the badi into sm34 so that the badi is shown under further template behaviour.

Changing appraisal header

Assignment was to control the validity of the calender header of the appraisal template
Badi notes :

Calender BADI : - HRHAP00_DOC_DEF_DV

tcode :-
se19 (BADI)

Cluster Table :- VC_T77HAP_CATEGORY (enter the Badi into this table first then OOAM)

tcode : sm34 to access the table

tcode :- OOAM (Enter into the template under "Layout")