[Tile-dev] More treeview improvements

[Joe E. <jen...@fl...>]

Initial development on the ttk::treeview widget
concentrated on getting the API right. I think that
has been more or less successful (but see below).
Between 0.7.8 and 0.8.2 much progress was made in
making it feel right, especially wrt. column dragging
and resize behavior.  I'm pretty happy with how that
works now too.

But as far as making it look right goes, it's
still pretty deficient.  If all you want is
a vanilla tree, that seems to be OK in 0.8.2;
but getting it to do anything beyond that has
proven to be difficult and awkward at best,
downright impossible at worst.  So that's
what I'd like to focus on next.

If anyone has any use cases where you tried to
get a ttk::treeview widget to look a particular way --
whether you succeeded or not -- send 'em my way.

It looks like the main stumbling blocks are
(a) the tag mechanism doesn't interact well with the
style database, and (b) the way the widget uses
the style database is overly-complicated and awkward.


On the API front, there are a number of operations
that probably warrant being built-in:

+ Test if an item has a particular tag
  (Proposed: [$tv tag includes $tag $item])

+ Return the list of items having a particular tag
  (Proposed: [$tv tag includes $tag] or [$tv tag items $tag])

+ Add a tag to an item or list of items
  (Proposed: [$tv tag add $tag $items])

+ Remove a tag from an item, list of items, or from all items
  (Proposed: [$tv tag remove $tag ?$items?])

+ [$tv identify row] should have been [$tv identify item].
  (Proposed: make the latter a synonym for the former, deprecate the former).

+ Replacement for the horrible 2-argument form of [$tv identify]
  (Proposed: [$tv identify (region|item|column|element) $x $y]


Any others I've missed?


--Joe English

  jen...@fl...