[ZDP] Ordering objects and ZDP Tools (again)

[Rik Hoekstra]

Maik,

I have been working on the 'orderer' problem we have been talking about
earlier.

The solution I have come up with after some experimenting requires some more
changes to the ZDP Tools than I had expected. So I thought to discuss this
first before implementing it on the ZDP site.

The elaborations are mainly due to the problems I had with acquisition: the
content and all other methods in the folder are listed if you use a standard
property for order., because they acquire it from the containing folder.
There are ways around it, but they're a bit clumsy. In the light of
yesterday's discussions about categories, subjects, topics etc. (in which
retaining order may also be of importance, especially when defining
hierarchies), I thought it would be a good idea to make the ordering
variable a bit more specific. So this is what I came up with:

- each folder/container type defines has a custom property named
'orderpropname' (for example FAQFolderorder).
- when a new instance is added to it, it is checked there is a orderpropname
(I still have to overcome the acquisitionproblem here) for the container. If
there is, the instance gets a local property orderpropname, and a value of
2000000 (or some arbitrarily large number). Your proposal of a default 0
seemed me to be not so intuitive to use for users changing orders, because
they have to put in numbers themselves. Unless, of course, you regard 0 as
an exceptional category, which I'm not sure I am for anyway. (Surpassing
2000000 items in a container wouldn't seem like a good idea anyway)

the rest is as we discussed before:
- ordering in the container is according to the values of the orderpropname,
only items with an orderpropname property set will get listed
- changing order is by a form with 'records' fields for all items.
etc.

If this proposal is carried out, it would mean giving quite a lot of folder
items a custom property (that is a custom propertysheet as well). WOuld this
cross your thoughts of maintainability of the ZDP Tools? Any other drawbacks
I haven't thought of? Does this it seem feasible to integrate this with
hierarchies?

Rik