Re: Restricting possible connections

[Lars Clausen <lrclause cs uiuc edu>]

On Sat, 26 Oct 2002, ml@knorke.in-berlin.de wrote:
> On Fri, Oct 25, 2002 at 08:05:51PM +0200, ed.hunter@seznam.cz wrote:
>> But, maybe, the function could be called only once - for the connection
>> object. If the connection object wants, it can call some function in the
>> two connected objects.  (But that would mean that it has to be able to
>> find about objects' classes. Can it do it now?)
>> 
>> so e.g.:
>> 
>> gboolean can_connect_objects (Object *self, Object *from, Handle
>> *from_h, Object *to, Handle *to_h)
> 
> In principle, one function call is preferable to two or
> three :-)  Question: How do I prevent a user from connecting
> a simple "line" with a UML class, if only the UML object
> "knows" about this access rights?  (Note: I'm relatively new
> to the dia internals...)

You don't.  The line would have to call the UML object to ask, and we can't
expect lines to do that.  It seems to me two calls are what we need.

-Lars

-- 
Lars Clausen (http://shasta.cs.uiuc.edu/~lrclause)| Hårdgrim of Numenor
"I do not agree with a word that you say, but I   |----------------------------
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