Rails - May 2006 - Working with topics and categories

Hello guys,

I''m a newbie in RoR and I have a problem. My DB structure is
=====================================topics table : id(int,11)
               name(varchar,255)

categories :   id (int,11)
               topic_id(varchar,255)
               name(varchar,255)
=====================================--Models:--
class Topic < ActiveRecord::Base
  has_many :categories
end
class Category < ActiveRecord::Base
  belongs_to :topic
end

I need page structure like this:
  <h3>Topic1</h3> (id = 1)
<ul><li>Category1</li> (topic_id = 1)
    <li>Category2</li> (topic_id = 1)
    <li>Category3</li> (topic_id = 1)
    <li>Category4</li></ul> (topic_id = 1)
  <h3>Topic2</h3> (id = 2)
<ul><li>Category1</li> (topic_id = 2)
    <li>Category2</li> (topic_id = 2)
    <li>Category3</li> (topic_id = 2)
    <li>Category4</li></ul> (topic_id = 2)
  <h3>Topic3</h3> (id = 3)
<ul><li>Category1</li> (topic_id = 3)
    <li>Category2</li> (topic_id = 3)
    <li>Category3</li> (topic_id = 3)
    <li>Category4</li></ul> (topic_id = 3)

... and so on.

How can I do this?

Thanks.

-- 
Posted via http://www.ruby-forum.com/.

@topic = Topic.find(:all, :include => "categories") in your
controller

then in your view

 <% @topic.each do |t| %>
   <h3> <%= t.name %> </h3>
   <ul>
     <% t.categories.each do |c| %>
       <li> <%= c.name %></li>
     <% end %>
   </ul>
 <% end %>

adam


On 5/28/06, Blinchik <oladywek@gmail.com> wrote:
>
> Hello guys,
>
> I''m a newbie in RoR and I have a problem. My DB structure is
> =====================================> topics table : id(int,11)
>                name(varchar,255)
>
> categories :   id (int,11)
>                topic_id(varchar,255)
>                name(varchar,255)
> =====================================> --Models:--
> class Topic < ActiveRecord::Base
>   has_many :categories
> end
> class Category < ActiveRecord::Base
>   belongs_to :topic
> end
>
> I need page structure like this:
>   <h3>Topic1</h3> (id = 1)
> <ul><li>Category1</li> (topic_id = 1)
>     <li>Category2</li> (topic_id = 1)
>     <li>Category3</li> (topic_id = 1)
>     <li>Category4</li></ul> (topic_id = 1)
>   <h3>Topic2</h3> (id = 2)
> <ul><li>Category1</li> (topic_id = 2)
>     <li>Category2</li> (topic_id = 2)
>     <li>Category3</li> (topic_id = 2)
>     <li>Category4</li></ul> (topic_id = 2)
>   <h3>Topic3</h3> (id = 3)
> <ul><li>Category1</li> (topic_id = 3)
>     <li>Category2</li> (topic_id = 3)
>     <li>Category3</li> (topic_id = 3)
>     <li>Category4</li></ul> (topic_id = 3)
>
> ... and so on.
>
> How can I do this?
>
> Thanks.
>
> --
> Posted via http://www.ruby-forum.com/.
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>
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Thanks Adam. Your answer is very helpful.
I have a question again. I have 3 columns, and 9 topics with N cats.

Topic 1    Topic 4    Topic 7
 Cat 1      Cat 1      Cat 1
 Cat 2      Cat 2      Cat 2
 Cat 3      Cat 3      Cat 3
Topic 2    Topic 5    Topic 8
 Cat 1      Cat 1      Cat 1
 Cat 2      Cat 2      Cat 2
 Cat 3      Cat 3      Cat 3
Topic 3    Topic 6    Topic 9
 Cat 1      Cat 1      Cat 1
 Cat 2      Cat 2      Cat 2
 Cat 3      Cat 3      Cat 3

How can I get 1st, 2nd and 3rd; 4th, 5th and 6th4 7th, 8th and 9th 
topics from the loop?
Thanks again!

-- 
Posted via http://www.ruby-forum.com/.

well you can use tables and every 3 rows insert a new 1 column table.

Or you can access the topic number order by doing

   t.categories[1] , t.categories[2] and so on instead of t.categories.each

adam


On 5/28/06, Vladislav Gorodetskiy <oladywek@gmail.com>
wrote:
>
> Thanks Adam. Your answer is very helpful.
> I have a question again. I have 3 columns, and 9 topics with N cats.
>
> Topic 1    Topic 4    Topic 7
> Cat 1      Cat 1      Cat 1
> Cat 2      Cat 2      Cat 2
> Cat 3      Cat 3      Cat 3
> Topic 2    Topic 5    Topic 8
> Cat 1      Cat 1      Cat 1
> Cat 2      Cat 2      Cat 2
> Cat 3      Cat 3      Cat 3
> Topic 3    Topic 6    Topic 9
> Cat 1      Cat 1      Cat 1
> Cat 2      Cat 2      Cat 2
> Cat 3      Cat 3      Cat 3
>
> How can I get 1st, 2nd and 3rd; 4th, 5th and 6th4 7th, 8th and 9th
> topics from the loop?
> Thanks again!
>
> --
> Posted via http://www.ruby-forum.com/.
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>
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