Rails fields_for form not showing up, nested form

Question

I have created an simple rails project. All worked fine until I tried to add a new model Paintings that belongs_to treatment and an Patient that has_many Paintings through Treatment. So somehow the nested form I created does not show up, I believe it has to do with the controller! Thanks, and greetings from Germany!

Treatments controller:

class TreatmentsController < ApplicationController
  def create
    @patient = Patient.find(params[:patient_id])
    @treatment = @patient.treatments.create(params[:treatment])
    redirect_to patient_path(@patient)
  end

  def destroy
    @patient = Patient.find(params[:patient_id])
    @treatment = @patient.treatments.find(params[:id])
    @treatment.destroy
    redirect_to patient_path(@patient)  
  end
end

And the form for treatments with nested fields_for that doesn't show up:

<%= form_for([@patient, @patient.treatments.build]) do |f| %>
  <div class="field">
    <%= f.label :content %>
    <%= f.text_area :content, :cols => "30", :rows => "10" %>
  </div>
  <div class="field">
    <%= f.label :category_id %>
    <%= f.collection_select :category_id, Category.find(:all), :id, :typ %>
  </div>

  <%= f.fields_for :paintings do |ff| %>
    <div class="field">
      <%= ff.label :name, 'Tag:' %>
      <%= ff.text_field :name %>
    </div>
  <% end %>

  <div class="field">
    <%= f.submit nil, :class => 'btn btn-small btn-primary' %>
  </div>
<% end %>

UPDATE:

Show Site:

<% @patient.treatments.each do |treatment| %>
  <tr>
    <td><%= treatment.category.try(:typ) %></td>
    <td><%= treatment.content %></td>
    <td><%= treatment.day %></td>
    <td><div class="arrow"></div></td>
  </tr>
  <tr>

try f.fields_for :paintings, Painting.new do |m|. Also, can u post the models code and the controller code in more details? — Prasad Surase, Jun 18 '13 at 18:21
haha your the best!! I tried it two days and now you made it with only one litlle bite add of code! Please move your comment to a answer so that i can set it to the right answer! — Em Sta, Jun 18 '13 at 18:25

score 79 · Accepted Answer · edited Mar 02 '14 at 01:48

79

Please try

= f.fields_for :paintings, Painting.new do |p|

edited Mar 02 '14 at 01:48

jvperrin

3,368
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answered Jun 18 '13 at 18:28

Prasad Surase

6,486
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Sorry but one more thing, how can i show the name of the image up? – Em Sta Jun 18 '13 at 18:30
1

i really dont have any idea about the model relationships or the fields. can u pls add them? – Prasad Surase Jun 18 '13 at 18:33
I mean in the same view i added to my post in the update! SO that ther is another with the name of the image – Em Sta Jun 18 '13 at 18:48
u cant display a painting name for a newly built painting object unless u have specified some default value. in the 'form' u cant cause the object fields hold 'nil' value unless u have specified a default value. in the updated view where u have listed the treatments, u can show the names of all the paintings for a particular treatment. – Prasad Surase Jun 18 '13 at 18:49
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/31964/discussion-between-surase-prasad-and-em-sta) – Prasad Surase Jun 18 '13 at 18:52

score 16 · Answer 2 · answered May 20 '16 at 15:20

16

Even the question is quite old, but you are missing the new that is crucial to this question. The methods destroy and create doesn't have anything with this issue. If you have a new method, which looks something like this:

class TreatmentsController < ApplicationController
  def new
    @patient = Patient.new
  end
end

Then the solution would be do modify the new method to "build" the paintings like this:

class TreatmentsController < ApplicationController
  def new
    @patient = Patient.new
    @patient.paintings.build
  end
end

answered May 20 '16 at 15:20

Aleks

4,866
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yes, but these demo codes has no `.build` action :-( https://github.com/nathanvda/cocoon_simple_form_demo/blob/master/app/controllers/projects_controller.rb#L26 – zx1986 Jul 14 '17 at 03:18
@zx1986 What do you mean by `they don't have build action`? I mean it shouldn't have the build action. The `build` is just a method to for the object. – Aleks Jul 14 '17 at 14:07

Mike Szyndel · Answer 3 · 2017-01-16T09:09:52.603

11

Try doing following in new action in controller

@patient.treatments.build

Check out build_association part http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html#method-i-belongs_to

You should also read about nested attributes. Use those for reference http://api.rubyonrails.org/classes/ActiveRecord/NestedAttributes/ClassMethods.html

edited Jan 16 '17 at 09:09

answered Jun 18 '13 at 18:13

Mike Szyndel

10,461
10
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1

this is a wrong syntax. try `@patient.treatments.build` – zx1986 Jan 15 '17 at 16:14

Alter Lagos · Answer 4 · 2023-01-06T06:06:44.557

9

Dumb error, but I was using:

<% f.fields_for :partner do |fp| %>

instead of:

<%= f.fields_for :partner do |fp| %>

edited Jan 06 '23 at 06:06

answered Jan 19 '21 at 23:32

Alter Lagos

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2

I have made the same mistake in `haml` file and wondering what the heck is wrong with my form for like 30 minutes... Oh my God... I use `- f.fields_for :partner do |fp|` instead of `= f.fields_for :partner do |fp|` – Fatima Sep 15 '21 at 08:25

score 0 · Answer 5 · answered Dec 10 '21 at 10:03

0

is case you have an association where it is optional:

in the controller:

@associated_model = @model.associated_model || @model.build_associated_model

in the view:

<%= form.fields_for :associated_model do |am| %>

answered Dec 10 '21 at 10:03

Mark Aldrin Aboganda

1

Rails fields_for form not showing up, nested form

5 Answers5

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