How to make a field editable again after displaying error msg (validation)

Question

Dear All,
In dialog programming, I have written a validation on a text field that it should not be left blank by the user, but after displaying the message the field becomes gray (non-editable). How can I make it editable once again after displaying the error message.
My code is as following:
***INCLUDE MZFBPS1_SAVE_DATAF01 .
*&      Form  save_data
      text
-->  p1        text
<--  p2        text
FORM save_data .
****************Check For Empty Fields Start
if ZFBPS_GATE_IN-truck_code is INITIAL
or ZFBPS_GATE_IN-truck_no is INITIAL
or ZFBPS_GATE_IN-transporter_code is INITIAL.
MESSAGE e020(zmatlist).
endif.
****************Check For Empty Fields Start
Regards,
Alok.

Answer 1

hi,
u can do it in chanin end chain.
For example if there are 10 fields in the screen and for 5 fields whenever the user enters wrong values u like to give some error message. You can declare that fields in the chain enchain so that only those fields will be input enabled and all other fields will disabled.
CHAIN.
FIELD chk_connobj.
FIELD chk_inst.
FIELD chk_devloc.
FIELD ehaud-haus.
FIELD eanl-anlage.
MODULE modify_screenfields.
ENDCHAIN.
*& Module modify_screenfields INPUT
* text
MODULE modify_screenfields INPUT.
CLEAR okcode.
okcode = sy-ucomm.
CASE okcode.
WHEN 'ENTER' OR 'EXECUTE'.
IF chk_connobj IS INITIAL AND chk_inst EQ c_x AND
chk_devloc EQ c_x.      -----------> ur condition
IF ehaud-haus IS INITIAL.
SET CURSOR FIELD 'EHAUD-HAUS'.
MESSAGE e000(zo_spa) WITH text-017. " message obj
ELSE
loop at screen.
if screen-name = 'FIELD_NAME'.
field-name-input = 1. -----------> chnges to non-edit mod
modify screen.
endloop.
ENDIF.
ENDIF.
ENDMODULE.
Rgds
Anver
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