Nested models with simple_form and paperclip - ruby-on-rails

Question

[This maybe a simple issue, but I just can't find a solution]
I'm trying to update an existing record with new data and add some image(s) to that record (via paperclip), however, my code doesn't show the paperclip field at all.
I've followed this example and also tried with this solutions, but nothing works.
I have two, models Hotel and HotelImage.
hotel.rb
class Hotel < ActiveRecord::Base
extend FriendlyId
friendly_id :slug_candidates, use: :slugged
validates :name, presence: true
validates :location, presence: true
has_many :hotel_images
accepts_nested_attributes_for :hotel_images
def slug_candidates
[
[:name, :location],
]
end
end
hotel_image.rb
class HotelImage < ActiveRecord::Base
belongs_to :hotel
#rails generate paperclip hotel_image image
has_attached_file :image, styles: { medium: "300x300>", thumb: "100x100>" }, default_url: "/images/:style/missing.png"
validates_attachment_content_type :image, content_type: /\Aimage\/.*\Z/
end
edit.html.erb
<%= simple_form_for #hotel, :url => admin_hotel_path, method: :put, html: { multipart: true } do |f| %>
<%= f.error_notification %>
<%= f.input :name %>
<%= f.input :location %>
<%= f.simple_fields_for :hotel_images do |ff| %>
<%= ff.input :image, as: :file %>
<% end %>
<%= f.button :submit %>
<% end %>
hotels_controller.rb
#other code
def update
#hotel = Hotel.friendly.find(params[:slug])
if #hotel.update(hotel_params)
redirect_to admin_hotels_path, notice: 'Hotel was successfully updated.'
else
render :edit
end
end
private
def hotel_params
params.require(:hotel).permit(:name, :location, :admin_id, hotel_images_attributes: [:hotel_id, :image])
end
Here's the print screen of the form, where you can see that the paperclip field is missing:
However, when I change f.simple_fields_for :hotel_images to, for example, f.simple_fields_for :foobars, the paperclip field is shown:
Note: the name and location attributes update just fine.

Answer 1

def update
#hotel = Hotel.friendly.find(params[:slug])
if #hotel.update(hotel_params)
redirect_to admin_hotels_path, notice: 'Hotel was successfully updated.'
else
render :edit
end
end
def edit
#hotel_images = #hotel.hotel_images.present? ? #hotel.hotel_images : #hotel.hotel_images.build
end
Try this code