select helper selected value and nested forms - ruby-on-rails

I have a nested form, like:
<% form_for #invoice do |f| %>
<%= render :partial => "invoice_item_fields", :locals => {:f => f} %>
<% end %>
and _invoice_items_fields:
<% f.fields_for :invoice_items do |builder| %>
<%= link_to_remove_fields "remove", builder %>
<%= builder.collection_select(:product_id, Product.all, :id, :name) %>
<%= builder.text_field :quantity, :size => 4,%>
<% end %>
When i submit the form and it not pass the validations it render the new action again. The thing is the selected value for :product_id is no remembered, but the :quantity is ok.
I read that i should setup an instance variable in the controller with the value of the selected option and then do something like:
<%= builder.collection_select(:product_id, Product.all, :id, :name, :selected => #selected_product) %>
but the thing is the application could have many :invoice_items, so i don't know what to do for the select field "remember" the values.
Thanks.

Can you post your controller code? I'd like to see where you're setting the invoice & invoice_item fields and how you're processing the form. I recently built an invoice & line_item application and might have some ideas... [Sorry I can't comment, but haven't hit that permission level.]

I solved this on another post. The thing was that my product_id was and string and not and integer at db level.

Related

belongs_to association in nested form does not post data correctly

I am having some difficulty to figure out why the post data from the form is not posted correctly.
I have to models: Child and Parent
in the form of Child i am nesting a form of Parent in this way:
<%
parent = (child.parent) ? parent : Parent.new
%>
<%=f.fields_for :parent, parent do |builder| %>
<%= render 'parent_fields', :fp => builder %>
<% end %>
The parent_fields form is as follows:
<% #all_parents = Parent.all %>
<% parent = fp.object %>
<%= fp.fields_for :parent do |builder| %>
<%= builder.input :parent_id, :as => :select, :label => 'Parent: ', :required => false,
:collection => options_from_collection_for_select(#all_parents, "id", "name", parent.id), :include_blank => '- Select -' %>
<% end %>
The posted data hash shows as follows:
"parent_attributes"=>{"parent"=>{"parent_id"=>"6"}, "id"=>"36"}
where 36 is the old parent id and 6 is the new one.
When i do update_attributes it does not work which is normal because it would work if the hash would be like this way:
...
"parent_id" => 6
"parent_attributes"=>{"id"=>"36", ....}
...
I am working on a legacy code. It is also possible that data was modified by javascript. The purpose of this post is to make sure that the way I am writing the form is the right way because I am new to nested forms.
Thank you
There are two possibly scenarios you want to consider:
1. A child needs to select an existing parent it belongs to.
2. A child needs to create a brand new parent that it belongs to.
It appears that you want to do #1, select an existing parent. If so, you do not need fields_for. Fields for is for creating new relations.
I'll show you some example code from an application I'm working on about schools, where a student belongs_to a grade level.
app/views/students/_form.html.erb
<%= form_for #student do |student_form| %>
<%= student_form.text_field :first %>
<%= student_form.text_field :last %>
<%= student_form.collection_select :grade_level_id, GradeLevel.all, :id, :name %>
<%= student_form.submit "Save" %>
<% end %>
Now, using your models (Child and Parent):
app/views/children/_form.html.erb
<%= form_for #child do |form| %>
<%= form.text_field :child_name %>
<%= form.number_field :age %>
<%= form.collection_select :parent_id, Parent.all, :id, :name %>
<%= form.submit "Save" %>
<% end %>
Note that I just put Parent.all straight into the collection_select. Creating #all_parents above isn't necessary.
EDIT
If you want to create new parents every time...
app/views/children/_form.html.erb
<%= form_for #child do |form| %>
<%= form.text_field :child_name %>
<%= form.number_field :age %>
<% form.fields_for :parent, #child.parent do |parent_fields| %>
<%= parent_fields.text_field :parent_name %>
<%= form.submit "Save" %>
<% end %>

Form within a form with rails

I've got a form for an order and with this, the user have to choose a category then associated product. As I want it to be dynamic, I wrote this :
_form.html.erb
<%= form_for(#order) do |f| %>
<%= f.collection_select :category_id, #categories_list, :id, :name, :prompt => "Selectionner" %>
<%= render :partial => 'products' %>
<%= f.submit 'Enregistrer', :class=>'button add'%>
<% end %>
_products.html.erb :
<%= form_for(Order.new, :remote => true) do |f| %>
<% if !#products.blank? %>
<%= f.label 'Produit :' %><br />
<%= f.select :product_id, #products.collect{ |s| [s.name,s.id]}, :prompt => "Selectionner" %>
<% else %>
<%= f.label 'Produit :' %><br />
<%= f.select :product_id, '' %>
<% end %>
<% end %>
in the controller :
def update_product_select
#products = Product.where(:category_id=>params[:id]).order(:name) unless params[:id].blank?
render :partial => "products", :layout => false, :locals => { :products => #products }
end
For the dynamic part, it works.
But when I click on the submit button, the product ID is not sent !
Can you tell me how is it possible for me to combine dynamic menu and form submitting please ?
Thanks.
I don't understand why you need two forms. Something is wrong here.
Explain a bit more on the workflow if possible.
I see you should either make use of fields_for if you are trying to edit other associated instances of #order.
For a dynamic menu, have a javascript event binding on the category that updates the products list based on the category. Let me know if you need an example.
I think you are looking for this: http://railscasts.com/episodes/88-dynamic-select-menus-revised
It needs a subscription, but you can also see the previous episode to get an idea if you dont want to subscribe.

formtastic render form fragment

Is there any way to render forms fragments with formtastic?
I have some checkboxes in my form which come from a one-to-many relationship.
So let's suppose a User form with a one-to-many Roles relationships. My formtastic form would look like
<%= semantic_form_for #user] do |f| %>
<%= f.inputs "Details" do %>
<%= f.input :name %>
<%= f.input :lastname %>
<% end %>
<%= f.inputs "Roles" do %>
<%= f.input :roles, :as => 'checkbox' %>
<% end %>
<% end %>
Now the line:
<%= f.input :roles, :as => 'checkbox' %>
Will output checkboxes for one-to-many. This works fine. But now I need to achieve some ActionController that outputs just the checkboxes... with no form and fieldset around. So that I can use it in my Ajax calls and update the "Roles" fieldset with fresh rendered checkboxes dinamically.
Any ideas? I'm stuck and can't figure out how to solve this.
I don't know if anyone had this need... anyway since nobody replied I found a solution by my self.
To render form fragments in the view (or partial view) file:
<% ref = nil %>
<% semantic_form_for [:admin, #user] do |f| %>
<% ref = f %>
<% end %>
<%= ref.input :roles, :as => :check_boxes, :required => false %>
Notice that only the last line actually outputs something, previous lines don't.
Experienced Rubyst or maybe even newbies may laugh at this... but I'm a noob(Ruby) and this is the best I could come up with. If any of you can tell a better way to do it I will be more than happy to learn.

Formtastic Confused on Has One Relationships

I'm a bit stuck on a 'has_one' and 'belongs_to' relationship and getting it to properly display in Formtastic. I have a person model that has one picture (a profile picture). I want the user to be able to select the picture using radio buttons. So far, I have:
<% form.inputs do %>
<%= form.input :picture, :as => :radio, :collection => #pictures %>
<% end %>
However, this fails (because the foreign key is stored on the 'belongs_to' side of associations in Rails. Any suggestions?
Ended up using custom controller code to fix. Use a variety of filters, etc.
Came across this in the "related" sidebar. I think this is a good use case for nested attributes -- from the Formtastic README:
Nested forms are also supported (don’t forget your models need to be setup correctly
with accepts_nested_attributes_for). You can do it in the Rails way:
<%= semantic_form_for #post do |form| %>
<%= form.inputs :title, :body, :created_at %>
<%= form.semantic_fields_for :author do |author| %>
<%= author.inputs :first_name, :last_name, :name => "Author" %>
<% end %>
<%= form.buttons %>
<% end %>
Or the Formtastic way with the :for option:
<%= semantic_form_for #post do |form| %>
<%= form.inputs :title, :body, :created_at %>
<%= form.inputs :first_name, :last_name, :for => :author, :name => "Author" %>
<%= form.buttons %>
<% end %>

Ruby on Rails: Drop down menu

I'm trying to create a drop down menu to allow a user to change an entry's field in my table. The user has one of three options -- hot, medium and cold.
I already have text_fields that do essentially the same thing for other fields, that all update when the user clicks on a submit_tag.
Is there an easy way to implement a drop-down box and have the result saved with the submit_tag ?
thanks,
-Chris
Here's the basic answer. The array of two element arrays is the critical part.
<% form_for #entry do |f| %>
<%= f.text_field :name %>
<%= f.select :temperature, [['Hot','hot'],['Medium','medium'],['Cold','cold']] %>
<%= f.submit %>
<% end %>
I'll assume 2 things:
That you are the <%= form_for #model_instance idiom (explained on section 2.2 of this guide).
That you want to store the "hot", "medium" and "cold" values as strings (not as numbers 1,2 and 3 or something similar) on your database.
Let's say that you have two fields, called :name and :temperature, controlled by two text_fields:
<% form_for #article do |f| %>
<%= f.text_field :name %>
<%= f.text_field :temperature %>
<%= f.submit "Create" %> <% end %>
<% end %>
Now you want to change the :temperature control to a dropdown list, accepting hot, medium and cold as values. Then you can do that this way:
<% form_for #article do |f| %>
<%= f.text_field :name %>
<%= f.collection_select :temperature, Article::TEMPERATURES, :to_s, :to_s,
:include_blank => true
%>
<%= f.submit "Create" %> <% end %>
<% end %>
You will now have to define the Article::TEMPERATURES constant in your Article model. It shouldn't be very difficult:
class Article < Activerecord::Base
TEMPERATURES = ['hot', 'medium', 'cold']
You may be wondering why I added the :include_blank part on the collection_select. This will add an "empty" option on your dropdown list. You will need that empty option when creating new objects, unless you want a "default" value to temperature.
http://api.rubyonrails.org/classes/ActionView/Helpers/FormTagHelper.html#M001730
I was working on something similar. I got this to work by simply adding either an enum or a constant(similar to what kikito said previously) in my model and then calling the select in my form.
Here's how it can work.
using the constant:
class ClassName < ActiveRecord::Base
TEMPERATURES = ['Hot', 'Medium', 'Cold']
end
bin/rails g migration add_column_to_table temperatures:string
_form.html.erb
<%= f.label :temperature %>
<%= f.select :temperature, ClassName::TEMPERATURE %>
or
using the enum:
class ClassName < ActiveRecord::Base
enum temperature: [:hot, :medium, :cold]
end
bin/rails g migration add_column_to_table temperatures:integer
_form.html.erb
<%= f.label :temperature %>
<%= f.select :temperature, ClassName.temperatures.keys %>
Hope that helps you!
You might want to consider formtastic gem which is lot less code.
<% semantic_form_for #stuff do |f| %>
<% f.inputs do %>
<%= f.input :name %>
<%= f.input :temperature, :as => :select,
:label => "Degree", :include_blank => false,
:collection => [["Hot", 1], ["Medium", 2], ["Cold", 3]] %>
<% end %>
<%= f.buttons %>
<% end %>
In accordance with all of the above answers, remember to do this last, important step:
Restart your server!
As a newbie, I was wondering why my array was not working even though I followed all the steps correctly.

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