observer implementation

Hello chaps, wonder if anyone can help me out on how to implement the
observer pattern.

Scenario: I have a bunch of different products with different attributes
and I want to update the values of the products attributes. I select the
right class for the product using the Factory pattern, the product knows
which attributes belongs to it (database fields) for updates and displaying
etc...

Ok so I want to give a means of inputting data to the products attributes
depending on which product is selected - I only want to display certain
text boxes that correspond to the correct products attributes.

Now I thought an observer might do the trick with it looping through the
products attributes container and calling "update" on the corresponding
input (textbox), but a textbox has no input method so I would have to
encapsulate the textbox and its "visible" method to give it the "update"
fuctionality needed .. this seems awefuly long winded and overblown to me.

Alternatively I could just set the visible property to either true or false
from within the observer.

Does anyone have a better way of dealing with this sort of setup?