From: lordbyte <markus.boelter@...>
Date: 2007-05-27T23:55:03+09:00
Subject: Return a "complete" class

Hi!

I have some problems with doing some kind of "my own controller" in
Ruby when returning a complete class.

Let's say we start with the following:

I have a ...
- ... model called Asset which has several attributes and methods.
- ... model called Picture which inherits from Asset (class Picture <
Asset)
- ... model called Video which inherits from Asset

So far so good. In a gallery controller, I know trough a parameter for
which kind of assets a user wants to search (videos, pictures, ...).
Now I had the following idea, which is not working for me and clearly
has some misunderstanding of OO. :-)

I created a class called Media which looks like this (pseudo-code):

class Media
  def initialize(asset_type)
    case asset_type
      when "picture"
        return Picture
      when "video"
        return Video
    end
  end
end

In my gallery-controller, I have a before-filter similar to:
params[:media] = picture
@media = Media.new(params[:media])

Later, I expect to do something like:
@media.find(:all)

The important thing is, that I only want to see pictures!

I see that it is not possible to return a complete class definition.
Even returning a "Picture.new" doesn't give me my methods defined in
the Picture model. I also don't expect to see @media.find(:all)
working, if @media was created with a Picture.new.

Does anybody has hints in which direction to look or how to solve this
problem?

Thanks in advance!

Cheers
  Markus