Rails 4 Form: has_many through: checkboxes

Question

Original question

Two resources: users and animals. When creating a user, the client selects check boxes to say how many

Answer 1

<% Animal.all.each do |animal| %>
   <label>
      <%= check_box_tag "user[animal_ids][]", animal.id, f.object.animals.include?(animal) %>
      <%= animal.name %>
   </label>
<% end %>

and you have to accept a hash with an array of ids on your controller params, something like

{  animal_ids: [] }

maybe reading this can help: http://millarian.com/programming/ruby-on-rails/quick-tip-has_many-through-checkboxes/

Answer 2

collection_check_boxes is a better option:

<%= f.collection_check_boxes(:animal_ids, Animal.all, :id, :name) do |animal| %>
  <%= animal.label { animal.check_box } %>
<% end %>