Re: construct-time properties and constructor

[murrayc t-online de (Murray Cumming)]

On Tue, 2001-11-13 at 23:45, Tim Janik wrote: 
> On 13 Nov 2001, Murray Cumming wrote:
> 
> > On Tue, 2001-11-13 at 19:53, Tim Janik wrote:
> > > On 13 Nov 2001, Murray Cumming wrote:
> > > 
> > > > I'm trying to fix the libgnomeui widgets so that they use construct-time
> > > > properties instead of _construct functions, but I'm finding that most of
> > > > properties would need to be dealt with all at once, instead of one after
> > > > the other.
> > > > 
> > > > It seems like this might be possible in the widget's constructor, which
> > > > gets passed an array of construct-time properties. But I am concerned
> > > > that these will be set a second time by the normal properties system.
> > > > Should I remove them from the GObjectConstructParam
> > > > *construct_properties array and pass a different array to the parent
> > > > class's constructor to stop this?
> > > > 
> > > > Although I've read about this in the archives, I can't seem to find an
> > > > example of a constructor that actually uses the construct_properties
> > > > array that's passed to it.
> > > 
> > > you shouldn't actually touch that array.
> > > just pass the array on when chaining to the parent class' constructor.
> > > then perform any construction tasks after chaining.
> > > to disable setting of these properties after the object has been
> > > constructed, create them with the G_PARAM_CONSTRUCT_ONLY flag.
> > 
> > OK, I'm trying that now. I need to access the GParamSpec::param_id field
> > to identify the correct array items, so I don't think that should be
> > marked <private>. There is a PARAM_SPEC_PARAM_ID macro, but that's in
> > gobject.c.
> 
> no, i said don't touch the array. that also implies you shouldn't
> evaluate it,

Sorry, I didn't understand.

So how can I get at that information? Should I use struct member fields which are set in set_property(), then read in those temporary values in the constructor after calling the base constructor? 
> do i _really_ need to make GObjectConstructParam an opaque
> typedef to stop people from this?

-- 
Murray Cumming
murrayc usa net
www.murrayc.com