Impossibility of modifiable invisible fields

[Leon Winter]

Hi Thomas,

it seems currently in the ncurses/forms library it is impossible to have a field
which one can normally edit but it being invisible.
Two options are currently available which impacts the visibility of a field:
O_PUBLIC und O_VISIBLE. Until now we have chosen !O_PUBLIC which is fine in
terms of focussability and hidden display but not when in comes to input: The
cursor is not advanced, therefore only one character can be inserted (which at
least is hidden). Naively switching to !O_VISIBLE made things worse as the field
cannot be focussed anymore. Digging into the sources yielded that O_SELECTABLE
requires both O_ACTIVE as well as O_VISIBLE. Thus by design it is not possible
to focus invisible fields.
Needless to say we want focussable, editable, invisible fields and I am now
wondering what the best approach would be. I assume O_SELECTABLE is currently
chosen as it is as certain places in the source code can then assume the field
is visible. I could look into that and might come up with yet another custom
field option to make visible fields selectable. I definitely think O_VISIBLE is
the way to go (over O_PUBLIC).

Regards,
Leon