Rails - Dec 2005 - Can scaffold generate listboxes in views? I''ve been unsuccessful.

I''ve created several different Rails applications but I''m
running
into the same trouble with each one.  Lets say I create an app called  
Test.  I type ''rails test'' and it generates the directory for
me.
Now I edit my database.yml file.  Then I create a database with  
Postgresql by typing createdb test.  Now I go into Postgresql by  
typing ''psql test''.

Here are my tables:

CREATE TABLE topics (
id               SERIAL PRIMARY KEY,
name        VARCHAR(100) NOT NULL
);

CREATE TABLE blogs (
id               SERIAL PRIMARY KEY,
title            VARCHAR(100) NOT NULL,
topic_id    INTEGER NOT NULL REFERENCES topics(id),
content     TEXT NOT NULL
);

Next, back in the test folder, I type ''script/generate scaffold Topic  
Topic''.  This creates my topic pages.  So far, so good.  Next, I type  
''script/generate scaffold Blog Blog''.  This creates my blog
pages.
When I go to view the blog pages at localhost:3000/blog, the only  
fields showing up on my page are the title and content.  Why isn''t  
the topic_id list box displayed?

I know I''ve gotten it to work once or twice but I don''t think
I''m
leaving out any steps, am I?

--
Jeff Self
Mac OS X (Apple Styling, Unix Power)

On Dec 17, 2005, at 2:21 PM, Jeff Self wrote:
> I''ve created several different Rails applications but I''m
running
> into the same trouble with each one.  Lets say I create an app  
> called Test.  I type ''rails test'' and it generates the
directory
> for me.  Now I edit my database.yml file.  Then I create a database  
> with Postgresql by typing createdb test.  Now I go into Postgresql  
> by typing ''psql test''.
>
> Here are my tables:
>
> CREATE TABLE topics (
> id               SERIAL PRIMARY KEY,
> name        VARCHAR(100) NOT NULL
> );
>
> CREATE TABLE blogs (
> id               SERIAL PRIMARY KEY,
> title            VARCHAR(100) NOT NULL,
> topic_id    INTEGER NOT NULL REFERENCES topics(id),
> content     TEXT NOT NULL
> );
>
> Next, back in the test folder, I type ''script/generate scaffold  
> Topic Topic''.  This creates my topic pages.  So far, so good.   
> Next, I type ''script/generate scaffold Blog Blog''.  This
creates my
> blog pages.  When I go to view the blog pages at localhost:3000/ 
> blog, the only fields showing up on my page are the title and  
> content.  Why isn''t the topic_id list box displayed?
>
> I know I''ve gotten it to work once or twice but I don''t
think I''m
> leaving out any steps, am I?
>
> --
>
> Jeff Self
> Mac OS X (Apple Styling, Unix Power)
Jeff-

	Scaffolding is not smart enough to handle relationships like that.  
You have to set that part up manually.

Cheers-
-Ezra Zygmuntowicz
WebMaster
Yakima Herald-Republic Newspaper
ezra-gdxLOakOTQ9oetBuM9ipNAC/G2K4zDHf@public.gmane.org
509-577-7732

I''m still new, and my syntax is probably off, but it is happening
because of your foreign key reference. Don''t forget to set your
assocations in the model, the ''has_many'' and
''belongs_to''. Once this
is done, you can access the value by: blog.topic:

For example, just to make the drop-down appear under ''Show''
when you
click on a particular blog (this should be done w/partials and such
really)

Edit your Controller for blogs, and add a line like this under Show:
@topics= Topics.find_all

Test it out by editing show.rhtml for blogs and adding a line like this:

<p>Topic</p><select name="blog[topic_id]">
   <% @topics.each do |topic| %>
       <option value="<%= topic.id %>"
         <%= '' selected'' if topic.id == @device.topic_id
%>>
         <%= topic.name %>
       </option>
   <% end %>
  </select></p>

I don''t know really where you''re stuck, some little more
direction
would better. This is to get you started, but is definitely not the
DRY way.

- Nic.


On 12/17/05, Jeff Self <jeff.self-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> I''ve created several different Rails applications but I''m
running
> into the same trouble with each one.  Lets say I create an app called
> Test.  I type ''rails test'' and it generates the directory
for me.
> Now I edit my database.yml file.  Then I create a database with
> Postgresql by typing createdb test.  Now I go into Postgresql by
> typing ''psql test''.
>
> Here are my tables:
>
> CREATE TABLE topics (
> id               SERIAL PRIMARY KEY,
> name        VARCHAR(100) NOT NULL
> );
>
> CREATE TABLE blogs (
> id               SERIAL PRIMARY KEY,
> title            VARCHAR(100) NOT NULL,
> topic_id    INTEGER NOT NULL REFERENCES topics(id),
> content     TEXT NOT NULL
> );
>
> Next, back in the test folder, I type ''script/generate scaffold
Topic
> Topic''.  This creates my topic pages.  So far, so good.  Next, I
type
> ''script/generate scaffold Blog Blog''.  This creates my
blog pages.
> When I go to view the blog pages at localhost:3000/blog, the only
> fields showing up on my page are the title and content.  Why isn''t
> the topic_id list box displayed?
>
> I know I''ve gotten it to work once or twice but I don''t
think I''m
> leaving out any steps, am I?
>
> --
> Jeff Self
> Mac OS X (Apple Styling, Unix Power)
>
>
>
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> Rails mailing list
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>

On Sunday 18 December 2005 05:54, Nic Werner wrote:
....
> Edit your Controller for blogs, and add a line like this under Show:
> @topics= Topics.find_all
>
> Test it out by editing show.rhtml for blogs and adding a line like this:
>
> <p>Topic</p><select name="blog[topic_id]">
>    <% @topics.each do |topic| %>
>        <option value="<%= topic.id %>"
>          <%= '' selected'' if topic.id ==
@device.topic_id %>>
>          <%= topic.name %>
>        </option>
>    <% end %>
>   </select></p>
>
> I don''t know really where you''re stuck, some little more
direction
> would better. This is to get you started, but is definitely not the
> DRY way.
>
> - Nic.
>
A slightly shorter way to do:

<%= select :blog, :topic_id, Topics.find(:all).map{ |t| [t.name, t.id]} %>

quite violating the MVC architecture, so a cleaner way would be to compute the 
Topics list in the controller as you did.

Francois