Rails - Oct 2005 - Using auto_complete_for with an attribute that doesn't map directly to a column in the db

Hi all,

I''ve been trying to figure out if I can use auto_complete_for with an  
attribute in a model that doesn''t map to a db column name directly,  
and I''ve had no luck.  It just doesn''t seem to work.

For example, I have  first_name and last_name columns in my person  
table, but i want to do auto_complete_for :person :full_name,  
(where :full_name = :first_name + :last_name.  Is this possible to do  
with the simple vanilla auto_complete_for helper?

Thanks in advance,
- Gabe


Heres my code, for reference...

in controllers/records_controller.rb:
     auto_complete_for :person, :full_name


in views/records/new.rhtml:
     Select Person: <%=  
text_field_with_auto_complete :person, :full_name %>


in models/person.rb:
     def full_name
         "#{@first_name} #{@last_name}"
     end

On 22-okt-2005, at 20:41, Gabe Hollombe wrote:
> Hi all,
>
> I''ve been trying to figure out if I can use auto_complete_for with
> an attribute in a model that doesn''t map to a db column name  
> directly, and I''ve had no luck.  It just doesn''t seem to
work.
>
> For example, I have  first_name and last_name columns in my person  
> table, but i want to do auto_complete_for :person :full_name,  
> (where :full_name = :first_name + :last_name.  Is this possible to  
> do with the simple vanilla auto_complete_for helper?
Most likely not, because autocomplete operates on the database level  
(it just uses a LIKE query to do attribute lookup).

You can write your own method which will involve adding concatenation  
to this query (look in the documentation).


-- 
Julian "Julik" Tarkhanov

Many thanks, Julian.  =)
- Gabe

On Oct 22, 2005, at 6:38 PM, Julian ''Julik'' Tarkhanov wrote:
>
> On 22-okt-2005, at 20:41, Gabe Hollombe wrote:
>
>
>> Hi all,
>>
>> I''ve been trying to figure out if I can use auto_complete_for
with
>> an attribute in a model that doesn''t map to a db column name  
>> directly, and I''ve had no luck.  It just doesn''t seem
to work.
>>
>> For example, I have  first_name and last_name columns in my person  
>> table, but i want to do auto_complete_for :person :full_name,  
>> (where :full_name = :first_name + :last_name.  Is this possible to  
>> do with the simple vanilla auto_complete_for helper?
>>
>
> Most likely not, because autocomplete operates on the database  
> level (it just uses a LIKE query to do attribute lookup).
>
> You can write your own method which will involve adding  
> concatenation to this query (look in the documentation).
>
>
> -- 
> Julian "Julik" Tarkhanov
>
> _______________________________________________
> Rails mailing list
> Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>

Gabe Hollombe <gabe@...> writes:
> 
> Hi all,
> 
> I''ve been trying to figure out if I can use auto_complete_for with
an
> attribute in a model that doesn''t map to a db column name
directly,
> and I''ve had no luck.  It just doesn''t seem to work.
> 
> For example, I have  first_name and last_name columns in my person  
> table, but i want to do auto_complete_for :person :full_name,  
> (where :full_name = :first_name + :last_name.  Is this possible to do  
> with the simple vanilla auto_complete_for helper?

I was just working on the same thing.

Yes, you can easily do this with Rails. No, you can''t do it with
auto_complete_for.  Using auto_complete_for causes Rails to dynamically generate
a "typical" AJAX action to respond to requests made by the browser
code
generated by the text_field_with_auto_complete helper. In this case,
"typical"
isn''t good enough, so you simply write your own action,
instead--it''s not hard.
Your action just has to have the right name (auto_complete_for_person_full_name)
and must render a partial (which you also write) that returns an HTML list of
the items you want displayed, formatted as you want them to appear.

Amy Hoy wrote a great tutorial on this subject:

http://www.slash7.com/articles/2005/08/13/
ajaxariffic-autocomplete-with-scriptaculous

Here''s a quick stab at what it might look like in your case:

# In controllers/records_controller.rb:
def auto_complete_for_person_full_name
  @people = (a query based on params[:person][:full_name], which
             contains what''s been typed so far)
  render :partial => ''full_name_auto''  # Name can be
whatever you want
end

# In views/records/_full_name_auto.rhtml
<ul class="people">
<% for person in @people do -%>
  <li class="person"><%= person.first_name -%> <%=
person.last_name -%></li>
<% end -%>
</ul>

--Forrest

Thanks, Forrest.  I''d found Amy''s tutorial, and was ultimately
going
to go the way of writing my own action anyway.  I was just wondering  
if there was a way I could get the vanilla auto_complete_for to check  
a non-db attribute in my model.  Looks like I''ll need to do it the  
way you mention, and looks like it won''t be hard at all. =)

- Gabe
On Oct 23, 2005, at 12:08 AM, Forrest Thiessen wrote:
> Gabe Hollombe <gabe@...> writes:
>
>
>>
>> Hi all,
>>
>> I''ve been trying to figure out if I can use auto_complete_for
with an
>> attribute in a model that doesn''t map to a db column name
directly,
>> and I''ve had no luck.  It just doesn''t seem to work.
>>
>> For example, I have  first_name and last_name columns in my person
>> table, but i want to do auto_complete_for :person :full_name,
>> (where :full_name = :first_name + :last_name.  Is this possible to do
>> with the simple vanilla auto_complete_for helper?
>>
>
>
> I was just working on the same thing.
>
> Yes, you can easily do this with Rails. No, you can''t do it with
> auto_complete_for.  Using auto_complete_for causes Rails to  
> dynamically generate
> a "typical" AJAX action to respond to requests made by the
browser
> code
> generated by the text_field_with_auto_complete helper. In this  
> case, "typical"
> isn''t good enough, so you simply write your own action, instead-- 
> it''s not hard.
> Your action just has to have the right name  
> (auto_complete_for_person_full_name)
> and must render a partial (which you also write) that returns an  
> HTML list of
> the items you want displayed, formatted as you want them to appear.
>
> Amy Hoy wrote a great tutorial on this subject:
>
> http://www.slash7.com/articles/2005/08/13/
> ajaxariffic-autocomplete-with-scriptaculous
>
> Here''s a quick stab at what it might look like in your case:
>
> # In controllers/records_controller.rb:
> def auto_complete_for_person_full_name
>   @people = (a query based on params[:person][:full_name], which
>              contains what''s been typed so far)
>   render :partial => ''full_name_auto''  # Name can be
whatever you want
> end
>
> # In views/records/_full_name_auto.rhtml
> <ul class="people">
> <% for person in @people do -%>
>   <li class="person"><%= person.first_name -%> <%=
person.last_name
> -%></li>
> <% end -%>
> </ul>
>
> --Forrest
>
>
> _______________________________________________
> Rails mailing list
> Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>