Rails: fields_for not working - ruby-on-rails

I was following this RailsCast about Nested Model Form, but something seems weird.
Here is Model relationship
class Question < ActiveRecord::Base
belongs_to :survey
end
class Survey < ActiveRecord::Base
has_many :questions
accepts_nested_attributes_for :questions
end
_form.html.erb(created by scaffold)
<div class="field">
<%= f.label :name %><br>
<%= f.text_field :name %>
</div>
<% f.fields_for :questions do |builder| %>
<div class ='question'>
<%= builder.label :content, "Question" %>
<br>
<%= builder.text_area :content, :rows => 3 %>
</div>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
survey_controller.rb
# GET /surveys/new
def new
#survey = Survey.new
3.times do |i|
#survey.questions.build
end
end
I was expecting it will display like
However,it didn't display 3 blocks of question.

You've missed a very small but important part of the form - actually outputting the f.fields_for call.
You need to call <%= f.fields_for :question (note the =) to actually output the generated form.

Related

Rails 4 fields_for not displaying field

I have two models that I would like to create with one form. I tried following this railscasts tutorial, but I just can't get the nested fields to display on the form. How can I make these nested fields appear?
Models
class Poll < ActiveRecord::Base
has_many :poll_answers, :dependent => :destroy
accepts_nested_attributes_for :poll_answers, allow_destroy: true
end
class PollAnswer < ActiveRecord::Base
belongs_to :poll
end
Controller
class PollsController < ApplicationController
def new
#poll = Poll.new
2.times { #poll.poll_answers.build }
end
private
def poll_params
params.require(:poll).permit([
:question,
poll_answers_attributes: [:answer]
])
end
end
View
<%= form_for(#poll) do |f| %>
<div class="field">
<%= f.label :question %><br>
<%= f.text_field :question %>
</div>
<% f.fields_for :poll_answers do |pa| %>
<p>Hello
<%= pa.text_field :answer %>
</p>
<% end %>
<%= debug #poll.poll_answers %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
You missed an =
<%= f.fields_for :poll_answers do |pa| %>
<p>Hello
<%= pa.text_field :answer %>
</p>
<% end %>

rails 4 nested form fields_for are not displayed

I just started learning Rails 4.2. The problem is that one field in the form is not being displayed.
I have restaurant, category and a dish. While creating a dish, the category and restaurant will also be inputted via /dishes/new.
Expected behaviour: Dish, Category and Restaurant fields are displayed.
Actual behaviour: Only Dish and Category fields are displayed.
Here are my models
models/restaurant.rb
class Restaurant < ActiveRecord::Base
has_many :categories
has_many :dishes, :through => :categories
end
models/category.rb
class Category < ActiveRecord::Base
belongs_to :restaurant
has_many :dishes
end
models/dish.rb
class Dish < ActiveRecord::Base
belongs_to :category
validates :name, :price, :category, :restaurant, :presence => true
accepts_nested_attributes_for :restaurant, :category
end
dish controller
def new
# I think this is where
# I am making a mistake
#dish = Dish.new
category = #dish.build_category
restaurant = category.build_restaurant
end
def create
#dish = Dish.new(dish_params)
respond_to do |format|
if #dish.save
.... # default stuff #
end
end
end
# strong params
def dish_params
params.require(:dish).permit(:name, :description, :price, restaurant_attributes: [:name], category_attributes: [:name])
end
Dishes views/dishes/_form.html.erb
<%= form_for(#dish) do |f| %>
<% if #dish.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#dish.errors.count, "error") %> prohibited this dish from being saved:</h2>
<ul>
<% #dish.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.label :nameWoW %><br>
<%= f.text_area :name %>
</div>
<div class="field">
<%= f.label :description %><br>
<%= f.text_area :description %>
</div>
<div class="field">
<%= f.label :price %><br>
<%= f.number_field :price %>
</div>
*** The restaurant name field is not being displayed **
<%= f.fields_for :restaurant do |restaurant| %>
<div class="field">
<%= restaurant.label :Restname %><br>
<%= restaurant.text_area :name %>
</div>
<% end %>
<%= f.fields_for :category do |category| %>
<div class="field">
<%= category.label :Catname %><br>
<%= category.text_area :name %>
</div>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
I have followed steps from rails guide, browsed questions on stackoverflow and read some blog posts as well but havent been able to figure out whats wrong. Some micro level mistake is blocking me :( . Anyone knows whats wrong ?
Thanks in advance.
UPDATE:
Hey I found a solution.
def new
#dish = Dish.new
#dish.build_category
#dish.category.build_restaurant
end
This works well.But this is just a part of the actual solution. I had to do lot of /dish/create controller modification as well. I think the entire solution will have to be put in blog post. Otherwise it wont make any sense. I will soon be posting and updating it here.
You can add this in your dish.rb
class Dish
delegate :restaurant, to: :category
end
Or you can do
<%= f.fields_for :restaurant, #dish.category.restaurant do |restaurant| %>
<div class="field">
<%= restaurant.label :Restname %><br>
<%= restaurant.text_area :name %>
</div>
<% end %>
I think you are missing:
class Dish
belongs_to :restaurant, through: :category
end
You have it on the other side (many) but not there. You could test this by trying to output #dish.restaurant on your form (should be empty but not nil).
def new
# I think this is where
# I am making a mistake
#dish = Dish.new
category = #dish.category.build
restaurant = category.restuarant.build
end

Rails 4: fields_for in fields_for

I am learning RoR and i am trying to find how to set a fields_for in another one with has_one models like this:
class Child < ActiveRecord::Base
belongs_to :father
accepts_nested_attributes_for :father
end
class Father < ActiveRecord::Base
has_one :child
belongs_to :grandfather
accepts_nested_attributes_for :grandfather
end
class Grandfather < ActiveRecord::Base
has_one :father
end
I used Nested Model Form Part 1 on Railscasts to get these:
In children_controller.rb:
def new
#child = Child.new
father=#child.build_father
father.build_grandfather
end
def child_params
params.require(:child).permit(:name, father_attributes:[:name], grandfather_attributes:[:name])
end
And my form:
<%= form_for(#child) do |f| %>
<div class="field">
<%= f.label :name %><br>
<%= f.text_field :name %>
</div>
mother:<br>
<%= f.fields_for :father do |ff| %>
<%= ff.label :name %>
<%= ff.text_field :name %><br>
grand mother:<br>
<%= f.fields_for :grandfather do |fff| %>
<%= fff.label :name %>
<%= fff.text_field :name %>
<% end %>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
I am trying to retrieve the datas with:
<%= child.father.name %>
<%= child.father.grandfather.name %>
but the grandfather's name won't work.
I cannot find the mistake(s)...anyone to help on this?
Thanks!
Try switching:
<%= f.fields_for :grandfather do |fff| %>
to:
<%= ff.fields_for :grandfather do |fff| %>
And switching:
params.require(:child).permit(:name, father_attributes:[:name], grandfather_attributes:[:name])
To:
params.require(:child).permit(:name, father_attributes:[:name, grandfather_attributes:[:name]])

Ruby on Rails, two models in one form

I have two very similar models Pretreatment and Diagnosis, that belong to the model Patient:
class Pretreatment < ActiveRecord::Base
belongs_to :patient
attr_accessible :content
end
class Diagnosis < ActiveRecord::Base
belongs_to :patient
attr_accessible :content
end
class Patient < ActiveRecord::Base
attr_accessible :age, :name, :city, :street, :number
has_many :anamneses
has_many :befunds
end
On the Patient show page I'm displaying two forms, one for the Preatreatment and another for the Diagnosis:
<%= form_for([#patient, #patient.preatreatments.build]) do |f| %>
<div class="field">
<%= f.label :conten %><br />
<%= f.text_field :content %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
<%= form_for([#patient, #patient.diagnosiss.build]) do |f| %>
<div class="field">
<%= f.label :content %><br />
<%= f.text_field :content %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
My question is how can I bring the two forms together, so that the user only has to press once the submit button? Im not sure but I think nested attributes is not the right thing to handle it, maybe thefields_for` tag?
Update I tried to use fields_for tag:
<%= form_for([#patient, #patient.pretreatment.build]) do |f| %>
<div class="field">
<%= f.label :content %><br />
<%= f.text_field :content %>
</div>
<%= fields_for([#patient, #patient.diagnosiss.build]) do |u| %>
<div class="field">
<%= u.label :content %><br />
<%= u.text_field :content %>
</div>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
But I get the error:
undefined method `model_name' for Array:Class in <%= fields_for([#patient,#patient.befunds.build]) do |u| %>
Use fields_for for the associated models.
There should be no square brackets arround the parameters of fields_for
In your code example, I cannot find the relation between Patient and Diagnosis, and the plural of diagnosis is diagnoses, you can specify this in config/initializers/inflections.rb:
ActiveSupport::Inflector.inflections do |inflect|
inflect.irregular 'diagnosis','diagnoses'
end
So your Patient model should contain
class Patient < ActiveRecord::Base
attr_accessible :age, :name, :city, :street, :number
has_many :diagnoses
end
And you can write in your form:
<div class="field">
<%= f.label :content %><br />
<%= f.text_field :content %>
</div>
<%= fields_for(#patient, #patient.diagnoses.build) do |u| %>
<div class="field">
<%= u.label :content %><br />
<%= u.text_field :content %>
</div>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
You can achieve that using nested attributes :
patient.rb
class Patient < ActiveRecord::Base
attr_accessible :age, :name, :pretreatments_attributes, :diagnosiss_attributes
has_many :pretreatments
has_many :diagnosiss
accepts_nested_attributes_for :pretreatments
accepts_nested_attributes_for :diagnosiss
end
patients_controller.rb
def show
#patient = Patient.find(params[:id])
#patient.pretreatments.build
#patient.diagnosiss.build
respond_to do |format|
format.html # show.html.erb
format.json { render json: #patient }
end
end
patients/show.html.erb:
<%= form_for #patient do |f|%>
<h3>Pretreatments:</h3>
<%= f.fields_for :pretreatments do |field| %>
<%= field.label "Content" %></div>
<%= field.text_field :content %>
<% end %>
<h3>Diagnosis:</h3>
<%= f.fields_for :diagnosiss do |field| %>
<%= field.label "Content" %></div>
<%= field.text_field :content %>
<% end %>
<%=f.submit %>
<% end %>
And that all
There are a few ways of doing this:
The way the fields_for works is you have a form_for for the parent model and within it you can place fields_for the models which belong to the parent. A good example is given in the Rails Docs
A simple and more extensible option over time but not very "semantic" one would be to use JavaScript/JQuery. You could trigger $("form #new_pretreatments").submit(); and the same for the Diagnosis once a button is clicked.
Maybe instead you could have just one model to store them both. For example a model called Disease. Each time a patient gets a disease a new one is created and it has columns for each the Diagnosis and Pretreatment. It's probably the best option instead of adding another model for each bit of info a patient can have.
You can use fields_for for the second model, which works like form_for but doesn't generate the form tags. See the docs.
There are some gems available for nested forms. one of them is awesome_nested_fields. I haven't used this earlier but that shows good code in documentation. Another one is simple_form.
Hope that helps!!!

Nested form not rendering Rails 3.2

The nested form in the view just won't render, unless I remove the f attribute, in which case the submit button will not work. I have two models, job and employer. I've been following the railscast here
job.rb
attr_accessible :title, :location, :employers_attributes,
belongs_to :employers
accepts_nested_attributes_for :employers
employer.rb
attr_accessible :companyname, :url
has_many :jobs
jobs_controller.rb
def new
#job = Job.new
#employer = Employer.new
end
_form.html
<%= form_for(#job) do |f| %>
<%= f.label :title %>
<%= f.text_field :title %>
<%= f.label :location %>
<%= f.text_field :location %>
<%= f.fields_for :employers do |builder| %>
<%= builder.label :companyname, "Company Name" %>
<%= builder.text_field :companyname %>
<%= builder.label :url, "Web Address" %>
<%= builder.text_field :url %>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
Any input would be brilliant - thanks
This happens because your job has no employers.
Change your code to this:
def new
#job = Job.new
#job.employer = #job.build_employer
end
In your job.rb change:
attr_accessible :title, :location, :employer_attributes,
belongs_to :employer
accepts_nested_attributes_for :employer
This line:
belongs_to :employers
Should be singulars:
belongs_to :employer
With this association you not need nested form you can use select for pick employer for each job.
But if you need many employers for each job and each job can have many employers see this screencast

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