Hi,

see first this url (sorry I not enough Karma to add complete url :( ):

h t t p : / / en.wikipedia.org/wiki/Strikethrough

to test :

create a new field type char normal_price_char with same string than normal_price ((to display the same name in view).

add it to the tree view and do invisible field normal_price in this same tree view.

in the form view, for fields normal_price and extra_price add the same attribute on_change function named by example onchange_normal_price_char with in body function this 2 fields.

in python class create the onchange function onchange_normal_price_char.

in onchange function, add test: if extra_price:

normal_price_char_temp = str(normal_price) (convert integer to string)

add in this condition a function which custom normal_price_char_temp with character "-" betweeen each char number (example : 1234 become 1-2-3-4).

use function attribute encode() with unicode U+0336 normal_price_char = normal_price_char_temp.encode('U+0336') (I hope this unicode will be known else search how to write this unicode correctly if this doesn't work)

else: normal_price_char = str(normal_price)

return {'value'{normal_price_char ': normal_price_char}}

perhaps you should do some personnal customs...

Hope this will help and work.

Don't forget to post your module to the openerp apps if it works ;)

Bye