Re: Patch to custom object: object-specific properties (preliminary)

["Marco Contenti" <m contenti libero it>]

----- Original Message -----
From: "Lars Clausen"
Sent: Wednesday, November 26, 2003 6:25 PM

> Reloading is a separate issue, let's get the attributes for shapes thing
> right first.
Agree.

> I applied your patch (though didn't commit that yet), and notice that you
> actually do what I was suggesting, kinda.
I think it's really too preliminary to commit. I'm still making changes and
will send an update quite soon.

> You're adding the custom
> attributes to the normal attributes in describe_props (I think it should be
> a part of shape loading, then we're sure it's done in time).
Among the changes I made, I needed to check whether custom_describe_props
has been called before custom_load, to avoid a crash.

> However, the saving part didn't seem to work.
Strange, it works fine to me, the code is there, at the end of custom_save.
If you send me your test case, I'll try tomorrow (it's getting late in my
time zone).

> I tried replacing the save function with object_save_using_properties,
> and it saved nicely (though without the 'custom:' prefix).
I didn't even know of that function, my knowledge of Dia internals is really
limited.

> You should be aware of the distinction between 'name'
> and the 'description' field of the props -- 'name' is only for internal
> identification (including in the save format), while 'description' is
> what's shown in the dialog.  You're using the same string for both, and
> then doing a hack in saving to mark them as custom.  I'd suggest adding the
> "custom:" mark in the name as soon as you create the property, then you're
> sure you won't be confused about when it's there.  Essentially, it should
> be done for the ShapeInfo, not for the Custom.
I'll check this, I should also add more attributes to the XML tag to
describe it better (description, default value...).

> Using object_load_using_properties to load (wrapped to give appropriate
> type) is a mite trickier, as you'll need to ensure the right shape is used
> in time for the rest of the load.  Moving the addition of extended
> attributes into the ShapeInfo creation code should help with this.
How should I use these functions and what's the advantage?

> You may want to ocnsider if the shape designer should be able to specify a
> default value.  It'd have to be used in custom_create.
See above.

Marco