From: Tim Hunter <TimHunter@...>
Date: 2008-08-04T06:59:29+09:00
Subject: Re: Why am I getting "undefined method" error?

laredotornado wrote:
> Hi,
> 
> I have a model, in which I have defined a method ...
> 
> class Form < ActiveRecord::Base
>         has_many :form_items
>         validates_associated :form_items
> 
> ...
> 
>         def self.has_items
>                 FormItem.count(:all, :conditions => ["form_id
> = ?", :id])
>         end
> end
> 
> 
> but when i try and call this method from another class,
> 
>         def new
>                 @form = Form.find_by_user_id(session[:user_id])
>                 if (@form == nil)
>                         false
>                 else
>                         @form.has_items
>                 end
>         end
> 
> 
> I'm getting the error below:
> 
> undefined method `has_items' for #<Form:0xb78f5e3c>
> 
> Any ideas?  Thanks, - Dave
> 
> 

By adding "self." to the has_items method definition, you've defined it 
as class method, but @form is an instance of Form. If you want to call 
has_items on an instance, remove the "self." in the method definition:

def has_items
    ...
end

-- 
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