I would use a before_save or what it is called if I were you.
Am 21.12.2012 19:40 schrieb "Walter Lee Davis" <wa...@wdstudio.com>:

>
> On Dec 21, 2012, at 1:12 PM, Dan Brooking wrote:
>
> > So is the way I'm doing it right?  Or just a way I happened to hack it
> to work?
> >
> > The way my code was looking was basically:
> >
> > Page.new(:url => 'http://www.yahoo.com')
> >
> > class Page < ActiveRecord::Base
> >   attr_accessible :url, :title
> >
> >   after_initialize :parse_page_params
> >
> >   def parse_page_params
> >     @title = "test"
> >   end
> >
>
> Have a look at the documentation for after_initialize -- it runs once,
> after Rails itself is fully initialized. Is that the point at which you
> mean to instantiate the instance variable @title? Which instance of its
> class would it attach to? Can you please describe what you intend to do
> with @title -- where it's going to be used?
>
> Walter
>
> > and this wasn't working...  I understand what you said above about the
> instance variables, methods, initializing, etc.. but still a little unclear
> about why that code doesn't work as I'm setting it.  Is it because Rails
> uses the method name of title which hasn't been initailized in my
> assignment above?
> >
> >
> >
> >
> > On Fri, Dec 21, 2012 at 12:43 PM, Walter Lee Davis <wa...@wdstudio.com>
> wrote:
> >
> > On Dec 21, 2012, at 12:37 PM, Dan Brooking wrote:
> >
> > > I posted a previous message about overriding initialize... because I
> was having issues setting some of the parameters.  I have a Page model that
> has:
> > >
> > > attr_accessible :url, :title, :doc, :domain
> > >
> > > and it's called via:
> > >
> > > Page.new(:url => 'http://www.yahoo.com')
> > >
> > > Since I'm only passing in the url to new, I needed to set the other
> parameters.  I was trying to do this via an after_initialize callback which
> wasn't working so tried overriding initialize... still not working.
> > >
> > > What I found out was that in my after_initialize, I was referring to
> title as @title which is why it was not working.  I switched it to
> self.title and it works fine.
> > >
> > > My question is - why?
> >
> > @title is an instance variable. Until you set it, it doesn't exist.
> Having a method on the model called title (or an accessor, or some other
> Rails magick) does not instantiate that method's return until and unless
> you ask for it by calling the method. Calling self.method_name just makes
> it clear which same-named method you really mean. Self is implied much of
> the time, but when you have all the many method_missing options available,
> it might not be the first one such that gets called.
> >
> > Walter
> >
> > >
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