Creating Variable Number of Models in One Form (Page 4 of 7)

I think the index isn't incrementing properly either because every time I click "Add another", the index remains at 2.

Thank you for the excellent tutorial.  It works wonderfully with a has many/belongs to association between tasks and project.

I am unable to get this to work on a has many through (many to many) association.  How can I build tasks from projects through say an "assignment" association table?

Last edited by usernameallan (2007-05-21 12:05:52)

The problem I'm having is with collection_select, when there is a validation error,the controller renders back the view, but the selected drop down is not the one i've selected before, it defaults back to the first value.

It only happens in the build model(eg. task) not the main one(eg. project). Is there fix?

Thank you for replying ryanb, it was the data type problem. i was going for a male and female collection_select and using tinyint, when i change it to int then can it default back to the proper value.

Another quick question if i wanna do simple yes/no select for the build model, can i do it without doing a table in mysql for just yes and no. i've done a simple select yes/no in the view but when it renders back, the value defaults back to the first value.

Thank you.

Last edited by nobit (2007-06-06 23:11:17)

Is it possible to implement the following structure:

Project has many task. Task has many resources and resources has whatever.

Build a tree like structure where project, task and resource are different models and create a variable number of all of them with technique showed in the tutorial ?

Thanks for the hint in the right direction. I forgot the nesting in "task...[resources]". I did not expect a complete solution but I may come again with some further questions..

So making sure the nested object is not nil does not fix the error:

I have a similar object:

@resume.education_histories[0].address

But in my case, I'm doing a deeper nesting of objects with a mix of collections.
My model:

class Resume < ActiveRecord::Base
  has_and_belongs_to_many :education_histories
end
class EducationHistory < ActiveRecord::Base
  has_and_belongs_to_many :resumes
  has_one :address
end

In my controller I have

def new
  @resume = Resume.new
  @resume.education_histories << EducationHistory.new(:address=>Address.new)
end

In my view I have:

<% @resume.education_histories.each_with_index do |education_history,index| %>
<% fields_for "resume.education_histories[#{index}]", education_history do |education_history_fields| %>
.... education history fields...
        
<% fields_for "resume.education_histories[#{index}][address]", education_history.address do |address_fields| %>
<p>
Street 1:<br/>
<%= address_fields.text_field :street_1 %>
</p>
<% end -%>
<% end -%>
<% end -%>

So, this doesn't appear to work, even after I specifically assign the address to the new education_history object in the zeroth position of my people collection. Anyone have any ideas?

It was on the initial form page. However, I changed up a few things (trial and error) and now I don't have that issue. I'm instead (of course) having another problem building the object arrays from the form in the controller. It all stems from how the naming in my fields_for tag is. To me, nothing seems clear on this.
So if I have a field tag that looks like this:

<% fields_for 
"resume.education_histories[#{index}][address]", 
@resume.education_histories[index].address do |@address_fields| %>

I get an address input tag like so:

<input id="resume.education_histories[0][address]_street_1"
 name="resume.education_histories[0][address][street_1]" size="30" type="text" />

But, if I look how the form params were submitted, I don't get the proper object graph set up and instead have params like this for the resume histories (dunno why the left '[' char gets dropped):

resume.education_histories"=>
{"0].[end_date(2i)"=>"6", "0].[degree_level"=>"-- Please select --", "0].[key_achievements"=>"",
 "0].[end_date(3i)"=>"19",
 "0].[start_date(1i)"=>"2007", "0].[start_date(2i)"=>"6",
 "0].[start_date(3i)"=>"19", "0"=>{"address"=>{"city"=>"", "zip"=>"",
 "street_1"=>"", "country"=>"United States", "street_2"=>"", "state"=>""}}

and params like this for the parent resume object:

"resume"=>
{"dreamjob_status"=>"Full time", "dreamjob_description"=>"", 
"dreamjob_title"=>"", "html_resume_link"=>"", "title"=>""}

Clearly, the education_histories should be nested properly in the resume object *and* the address should be nested properly in each education_histories obj.
The error Rails comes back with is

I've been playing around with different fields_for names with no luck yet.

Try this:

<% fields_for
"resume[education_histories][#{index}][address]",
@resume.education_histories[index].address do |@address_fields| %>

Also make sure there's no missing open/close square brackets in any of the names. Hopefully that will format it properly in the params.

Edit: nevermind. You have it right in your last post. Instead try creating an accessor method in the education histories model to handle the address:

# in EducationHistories
def address_attr=(attributes)
  build_address if address.nil?
  address.attributes = attributes
end

Then change the name to match this:

<% fields_for
"education_histories[#{index}][address_attr]",
@resume.education_histories[index].address do |@address_fields| %>

Last edited by ryanb (2007-06-19 14:34:20)