I've got a model Product in my Rails application, its attributes can be edited, and I want to let user comment every change he makes (a comment can be blank, though). So, Product has_many :comments, it accepts_nested_attributes_for :comments and rejects it if the comment is blank.
Hence, the edit form for Product is a multi-model form. The problems I faced are:
Fields_for helper renders text areas for all comments belonged to the product, so the user can edit all previous comments. I need it to render fields for the new one only.
If validation breaks, and there are no comments, fields_for renders nothing. Should I perform #product.comments.build in the view before fields_for statement every time, or there is more elegant way to do it?
Maybe I'm wrong and fields_for isn't suitable in this situation?
Base on Tots answer I just made it a little simplier (Rails 3 compatible):
<%= f.fields_for :comments, #product.comments.build do |comment| %>
<%= comment.label :comments %><br />
<%= comment.text_area :content %>
<% end %>
<% f.fields_for(:comments, Product.reflect_on_association(:comments).klass.new)
do |builder| %>
<%= builder.label :comment %>
<%= builder.text_area :comment, :rows => 3 %>
<% end %>
Related
I have a has_many association between Items and their Components through a table called ComponentItems. ComponentItems contains a column quantity in addition to item_id and component_id. How is it possible to add a number_field to my form that shows the quantity of each component required for an item? The form must contain a number_field for each Item in the database, even if no relationship exists (i.e. #item.component_ids.empty? == true).
class Item < ActiveRecord::Base
has_many :components, through: :component_items
has_many :component_items
end
class Component < Item
has_many :items, through: :component_items
has_many :component_items
end
class ComponentItem < ActiveRecord::Base
belongs_to :item
belongs_to :component
end
I believe I've tried every permutation of model, controller and form_builder possible, except the correct one.
In response to the answer below, here's a form that shows a checkbox and the item code for component items that make up one particular item;
<%= form_for [#item] do |f| %>
<%= f.collection_check_boxes :component_items, Item.active.where.not(sku: #item.sku).sort_by{|n| n.sku}, :id, :sku do |b| %>
<%= b.check_box %> <%= b.label %><br/>
<% end %>
<% end %>
So, ideally I'd replace the check_box with a number_field for quantity. How?
So it seems what I wanted is not so straightforward after all. In the end I opted for using some jQuery for adding extra Components to Items via a separate form. Trying to add/remove components and adjust the quantities was beyond me, so choosing to use separate forms for each user action seemed simpler. It may not be the most user-friendly way of working but it's the best I have.
To edit the quantities I did the following;
<% #item.component_items.each do |x| %>
<%= hidden_field_tag "item[component_items_attributes][][id]", x.id%>
<%= label_tag x.component.sku, x.component.sku.upcase, :class=>"col-md-3 control-label" %>
<%= number_field_tag "item[component_items_attributes][][quantity]", x.quantity, :class=>"col-md-5"%>
<%end %>
and ensured the Item model accepted nested attributes for component_items. Finally, add the nested params array for multiple component_items to items_controller.rb...
def item_params
params.require(:item).permit(
:component_items_attributes =>[:component_id, :item_id, :quantity, :id]
)
end
Note I didn't use fields_for which seemed to generate an extra component_items_attributes array that didn't make any sense at all.
This should work:
#item.components.to_a.sum(&:quantity)
This will throw an error if quantity on some component is nil, so you may try like this to avoid errors:
#item.components.to_a.map(&:quantity).compact.sum
UPDATE
<% #item.component_items.each do |component_item| %>
<%= form_for(component_item) do |f| %>
<div class="field">
<%= f.label :quantity, 'Quantity' %><br />
<%= f.number_field :quantity %>
</div>
<% end %>
<% end %>
I have three Models:
class Question < ActiveRecord::Base
has_many :factor_questions
has_many :bigfivefactors, through: :factor_questions
accepts_nested_attributes_for :factor_questions
accepts_nested_attributes_for :bigfivefactors
end
class Bigfivefactor < ActiveRecord::Base
has_many :factor_questions
has_many :questions, through: :factor_questions
end
and my join-table, which holds not only the bigfivefactor_id and question_id but another integer-colum value.
class FactorQuestion < ActiveRecord::Base
belongs_to :bigfivefactor
belongs_to :question
end
Creating an new Question works fine, using in my _form.html.erb
<%= form_for(#question) do |f| %>
<div class="field">
<%= f.label :questiontext %><br>
<%= f.text_field :questiontext %>
</div>
<%= f.collection_check_boxes :bigfivefactor_ids, Bigfivefactor.all, :id, :name do |cb| %>
<p><%= cb.check_box + cb.text %></p>
<% end %>
This let's me check or uncheck as many bigfivefactors as i want.
But, as i mentioned before, the join model also holds a value.
Question:
How can I add a text-field next to each check-box to add/edit the 'value' on the fly?
For better understanding, i added an image
In the console, i was able to basically do this:
q= Question.create(questiontext: "A new Question")
b5 = Bigfivefactor.create(name: "Neuroticism")
q.bigfivefactors << FactorQuestion.create(question: q, bigfivefactor: b5, value: 10)
I also found out to edit my questions_controller:
def new
#question = Question.new
#question.factor_questions.build
end
But i have no idea how to put that into my view.
Thank you so much for your help!
Big Five Factors model considerations
It looks like your Bigfivefactors are not supposed to be modified with each update to question. I'm actually assuming these will be CMS controlled fields (such that an admin defines them). If that is the case, remove the accepts_nested_attributes for the bigfivefactors in the questions model. This is going to allow param injection that will change the behavior sitewide. You want to be able to link to the existing bigfivefactors, so #question.factor_questions.first.bigfivefactor.name is the label and #question.factor_questions.first.value is the value. Notice, these exist on different 'planes' of the object model, so there wont be much magic we can do here.
Parameters
In order to pass the nested attributes that you are looking for the paramater needs to look like this:
params = {
question: {
questiontext: "What is the average air speed velocity of a sparrow?",
factor_questions_attributes: [
{ bigfivefactor_id: 1, value: 10 },
{ bigfivefactor_id: 2, value: 5 } ]
}
}
Once we have paramaters that look like that, running Question.create(params[:question]) will create the Question and the associated #question.factor_questions. In order to create paramaters like that, we need html form checkbox element with a name "question[factor_questions_attributes][0][bigfivefactor_id]" and a value of "1", then a text box with a name of "question[factor_question_attributes][0][value]"
Api: nested_attributes_for has_many
View
Here's a stab at the view you need using fields_for to build the nested attributes through the fields for helper.
<%= f.fields_for :factor_questions do |factors| %>
<%= factors.collection_check_boxes( :bigfivefactor_id, Bigfivefactor.all, :id, :name) do |cb| %>
<p><%= cb.check_box + cb.text %><%= factors.text_field :value %></p>
<% end %>
<% end %>
API: fields_for
I'm not sure exactly how it all comes together in the view. You may not be able to use the built in helpers. You may need to create your own collection helper. #question.factor_questions. Like:
<%= f.fields_for :factor_questions do |factors| %>
<%= factors.check_box :_destroy, {checked => factors.object.persisted?}, '0','1' %> # display all existing checked boxes in form
<%= factors.label :_destroy, factors.object.bigfivefactor.name %>
<%= factors.text_box :value %>
<%= (Bigfivefactor.all - #question.bigfivefactors).each do |bff| %>
<%= factors.check_box bff.id + bff.name %><%= factors.text_field :value %></p> # add check boxes that aren't currently checked
<% end %>
<% end %>
I honestly know that this isn't functional as is. I hope the insight about the paramters help, but without access to an actual rails console, I doubt I can create code that accomplishes what you are looking for. Here's a helpful link: Site point does Complex nested queries
Have a page where there are multiple input fields of the same thing, Posts. Right now, when a user enters in a question for, let's say 3 fields, the only one that saves to the database is the last one. Whereas, it should save all three and give them each it's own post_id. Also; if the user doesn't enter anything in for the other fields, it should not save in the database either.
new_step_4_html.erb
<%= form_for(#post) do |f| %>
<%= f.text_field :content %>
<%= f.text_field :content %>
<%= f.text_field :content %>
<% end %>
projects_controller.rb
def new_step_4
#post = Post.new
end
Right now, all it does is submit one :content field, obviously because they all share the same id/value. Unfortunately, the Railscasts #197 applies for nested forms, so the javascript and helper stuff he does all applies for nested. I would think this is something simple. Person from IRC mentioned I could do some sort of '3.times' code into the view file or something?
First of all you will probably have to edit the model of you post.
post.rb
has_many :contents, :dependent => :destroy
accepts_nested_attributes_for :contents
You will need another model to store the content fields.
so first generate a model
rails g model content post_id:integer body:text
the model
content.rb
belongs_to :post
Now, in stead of doing <%= f.text_field :content %> a few times, let rails create them, because now you basically let them overwrite each other.
3.times do
content = #post.content.build
end
the form view will be something like this:
<%= form_for #post do |f| %>
<%= f.fields_for :contents do |builder| %>
<%= builder.label :body, "Question" %><br />
<%= builder.text_area :body, :rows => 3 %><br />
<%= end %>
<p><%= f.submit "Submit" %></p>
<% end %>
I did not test this code, but the idea should be correct. Let me know if you need more info.
I'm trying to make an app where a user can save goals, milestones for those goals, tasks for the milestones, and tasks for the goal itself. I'm using polymorphic associations, but making a form to input all of them has proven difficult. The problem is that the milestones aren't saving at all, and the milestone tasks are being listed in the database as having type "Goal" instead of type "Milestone" The models and database are set up like the top answer for this question.
I'm hoping someone could take a look at my form_for implementation and see if it's correct, or if the problem is somewhere else. Let me know if you need to see some other code.
<%= nested_form_for #goal do |f| %>
<%= render 'shared/error_messages', :object => f.object %>
<%= render 'shared/goal_fields', :f => f %>
<%= f.fields_for :milestones do |ff| %>
<%= render 'shared/milestone_fields', :f => ff %>
<% end %>
<%= f.fields_for :tasks do |ff| %>
<%= render 'shared/task_fields', :f => ff %>
<% end %>
<%= f.link_to_add "Add Milestone", :milestones %>
<%= f.link_to_add "Add Task", :tasks %>
<%= f.submit %>
<% end %>
The Rails form builder method fields_for allows you to nest attributes for multiple records. This part of your code looks correct (assuming that your partials are working). You can make your fields_for line more explicit by building the relationship off of the goal object as follows:
<%= f.fields_for :milestones, #goal.milestones.build do |ff| %>
<%= render 'shared/milestone_fields', :f => ff %>
<% end %>
Ensure that your models have the following code in order to process the parameters that will be passed to each of these models:
# app/models/goal.rb
has_many :milestones
has_many :tasks
accepts_nested_attributes_for :milestones
accepts_nested_attributes_for :tasks
# app/models/milestone.rb
has_many :tasks
accepts_nested_attributes_for :tasks # For tasks on milestones
Also ensure that if you are using attr_accessible to lock down your model attributes from mass-assignment, that these entries have corresponding entries (milestones_attributes, tasks_attributes, etc)
When you submit the form, look at the rails development log, and ensure that you see the parameters come through in a format similar to:
{:goal => {:milestones_attributes => {:tasks_attributes => {}, :tasks_attributes => {} }}
If all this data is going through, but the record is still not being saved, check for "ROLLBACK" entries in the log that might indicate that a record is not valid, and could not be inserted.
More info on nested_attributes can be found here:
http://api.rubyonrails.org/classes/ActiveRecord/NestedAttributes/ClassMethods.html
Info on the form helpers utilizing these nested attributes can be found here:
http://api.rubyonrails.org/classes/ActionView/Helpers/FormHelper.html#method-i-fields_for
I have a user and a profile model. One user can have many profiles. I need to access only one information from the profiles section (viz the phone number) in my user model during the user creation process. Hence I'm trying to get it done through attr_accessible. My user.rb looks like this.
has_many :profiles
attr_accessible :handle, :email, :password, :profile_mobile_number
attr_accessor : :profile_mobile_number
The problem that I'm facing is that when I try to call the getter method profile_mobile_number in a method in user.rb (the method is private, though I think it doesn't matter), I'm getting a null value. I use the following in my users/new.html.erb form
My question is what is the right way to do this? Should I use <% f.fields_for :profile do |ff| -%> or <% f.fields_for :profiles do |ff| -%> (notice that the second one is plural). When I use the plural :profiles, I don't even see the fields on the form. What am I missing here? And what is the tense that needs to be used in model user.rb? :profile_phone_number or :profiles_phone_number? Thanks.
You could do something like the following:
<% form_for #user, :url => { :action => "update" } do |user_form| %>
...
<% user_form.fields_for :profiles do |profiles_fields| %>
Phone Number: <%= profiles_fields.text_field :profile_mobile_number %>
<% end %>
<% end %>
But since you already have an association, then might as well use 'accepts_nested_attributes_for'
You should watch RailsCasts Nested Model Form.
thanks Ryan Bates great work.
http://apidock.com/rails/v3.2.8/ActionView/Helpers/FormHelper/fields_for
This api dock link list many Nested Attributes Examples including one-to-one, one-to-many. It's very helpful!
You can use 'accepts_nested_attributes_for' to do this; but there's a little trick in forms:
You must use the singular, and call fields_for for each profile, like this:
<% form_for #user do |f| -%>
<% #user.profiles.each do %>
<% f.fields_for :profile_attributes, profile do |ff| -%>
<% end %>
Notice that is :profile_attributes, instead of just :profile.