[Debconf-devel] Debconf - adding "treeselect" type(s)?

[Steve McIntyre]

Hi!

Timo wrote:
>29.11.20 20:21 Steve McIntyre:
>> On and off, I've been hacking on tasksel for quite a while to improve
>> the UI there and add better support for things like Blends. I've made
>> some progress in my hacking, but I think I've hit a brick wall and I
>> need to change tack. :-/
>> 
>> What I've ended up doing so far is hacking tasksel to give a poor
>> *approximation* of a tree-style layout: classifying some existing
>> tasks under headers and building a tree, then displaying each of the
>> nodes of the tree one level at a time via the existing debconf
>> setup. It just about works, but it's ugly as all hell and I'm not
>> happy with where I've got to. I've sunk a lot of development time into
>> this, but I don't think it's ready to fly this way. :-(
>> 
>> What I *actually* need here is proper support in debconf for
>> tree-style selection. I'm thinking of adding that, adding new types
>> "treeselect" as a tree-equivalent of "select" and "multitreeselect" as
>> an extension of "multitselect". The first one may not even be needed,
>> but would be a trivial simplification of the second, so *meh*.
>
>What are the proposed semantics of this multitreeselect?
>
>If we imagine something like:
>
>[ ] a
>  [ ] a/b
>  [ ] a/c
>[ ] b
>  [ ] b/a
>
>Would checking "a" automatically also check "a/*"?
>Is it only about UI, meaning "a/*" would be collapsed under "a"?
>Shall it be possible to check "a", but uncheck "a/b"?

Yes, I'm thinking just about UI here: my plan would be to not have
anything *selectable* at "a" - it would just toggle the display of the
"a/*" subtree in those frontends that can display such a thing. So,
yes: it would be possible to hit "a" and then not show have any of
"a/*" selected.

For simpler frontends that can't handle that kind of toggling, I'm
thinking we'd just display the tree nodes ("a", "b") as headings to
the user to group things together. Maybe we could do better - ask an
extra question at that point in the listing to show the user that
sub-tree or not.

-- 
Steve McIntyre, Cambridge, UK.                                steve at einval.com
"You can't barbecue lettuce!" -- Ellie Crane