Subject Re: [IBO] Suggestion For IBO 4.0
Author Geoff Worboys
Lester,

> I have a part of my system that is crying out for a
> tree structure, but has been on the back burner for
> some time. All the rest of the stuff is now in babysit
> mode while the little niggles are cleared, so it is time
> to look at it.
>
> The problem seems to me how to control the tree.

Somewhere in my archives I have the beginnings of a treeview for
IBObjects. It was partly working but I never got around to finishing
it. If you are interested I can try and find it and send it to you.

My approach to the situation was...

1. Build a non-visual TreeSource component - linked to TIB_DataSource
and provide definition of the field for display on the tree. It also
linked to other TreeSource components to form a heirarchy.

2. Build the TreeView itself which linked to the TreeSource.


This allowed a very flexible arrangement, where the treeview could
actually display self-referencing information via a TreeSource or it
could reflect a heirachy of different datasets using linked TreeSource
components. This arrangement also allowed the treeview component to
isolate itself (somewhat) from the specific implementation of the
dataset. (It also saved me from writing complicated designtime
editors to provide tree setup. ;-)

I dropped development at the time - due to other priorities. I dont
intend to go back to this code, because I intend to try and use the
infotreegrid from Dream Company. It uses a similar mechanism to that
described above but is much more powerful than anything I have time to
develop.

If you think my old source may help I can try to find it. I dont
think I will have erased it completely - so unless it got misplaced in
one of my upgrades it should still be around on a CD somewhere.

Geoff Worboys
Telesis Computing