pass array hidden field in nested model rails

Question

I have following code in my view:

    <% @m1.map(&:id).each do |id|%>

    <%= b.fields_for :modul1hours do |f| %>

    <%= f.hidden_field :mo         


        

Answer 1

In this line:

<%= f.hidden_field :modul1_id, id %>

You are saying that you want the hidden field binded with modul1hour modul1_id method and options being id. Second parameter for FormBuilder hidden_field is expected to be a hash (which is then merged against default options). To do what you want do:

<%= f.hidden_field :modul1_id, value: id %>

Answer 2

Hidden fields aren't really the issue here

Apart from @BroiStatse's answer, I can see the issue as how you handle the params on your controller

---

Nested Models

Sending data to a controller sends that data to the relevant models. This is normally handled with accepts_nested_attributes_for, but can be handled manually too

From your controller code, I can't see how you're dealing with your extra data, but your error is caused by the incorrect merge of the params

Instead of saving the data manually, I would use the accepts_nested_attributes_for to save the data, like this:

#app/models/project.rb
Class Project < ActiveRecord::Base
    accepts_nested_attributes_for :modul1hours
end

This will pass the params to your modul1hours model, where you'll then have to capture them with the relevant attr_accessible actions

---

f.fields_for

In order to get accepts_nested_attributes_for working properly, you have to ensure you use the f.fields_for function correctly.

You have to first build the ActiveRecord objects in your new controller action, like this:

def new
    @project = Project.new
    @project.modul1hours.build
end

Your problem is that you're then cycling through the ID's of your modul1hours model, yielding the f.fields_for artificially. Rails will only output an f.fields_for if the ActiveRecord object has been built in the controller:

"30" %>

This RailsCast gives you a better idea about this

What I would do is this:

#app/controllers/projects_controller.rb
def new
    @project = Project.new
    @m1.map(&:id).each do |i|
        @project.modul1hours.build
    end
end

#app/views/projects/new.html.erb
<%= b.fields_for :modul1hours do |f| %>
    <%= hidden_field_tag :id, value :id %>
    <%= f.text_field :module_est_hours, :size => "30" %>
<% end %>

I'm still thinking about how I would assign the ID's to the hidden field

---

Update

Try this:

#app/controllers/projects_controller.rb
def new
    @project = Project.new
    @project.modul1hours.build
end

Replace modul1hours with whatever your projects has_many of