296431 - <preference type='custom'/>: for saving in places other than user prefs

Status: NEW

(Toolkit :: Preferences, enhancement)

Description

[Nickolay_Ponomarev]

It would be really nice, if a feature similar to
onpreferenceread/onpreferencewrite (setter and getter for UI element's |value|)
could be implemented on <preference>'s side.

What I mean is, sometimes we need to store a value outside user prefs. It would
be nice to be able to use other goodness of prefs bindings (like, sync of
different UI elements, instantApply handling, subdialogs handling) for such "prefs".

If this still isn't clear, here's an example. In my extension, I need to save
user's password. I use password manager for that. I'd like to be able to write
the prefs UI as if I stored the password in user prefs, but use a special kind
of pref, like:
<preference type="custom" 
  onprefread="return read_from_password_manager();" 
  onprefwrite="return write_to_password_manager();"/>

to store the password in password manager, instead of user prefs.

Hope that's clear.