how textbox disable and accept only from lov

[mfa786]

hi master
sir
my user some time feed rough data i want to restric that he only select value from lov not give from key board mu text bot disable and accept only lov

please give me idea how textbox disable and accept only from lov

some body give me this idea
=======
use a text-item
link in the item your lov and check "Validate from List" to Yes
set "Enabled" to Yes
set "Insert Allowed" to No
set "Update Allowed" to No
=========
i set this property

Validate from List= Yes
Enabled= Yes
Insert Allowed= No
Update Allowed= No

but my textbox total enable = no

when i press F9 system not show the lov

no curser inter in text box

please give me idea how only lov work

thanking you

aamir