accept nested attributes with rails4 strong params

accept nested attributes with rails4

class ItemsController < ApplicationController
  #rest of your methods
  # ......
  private
   def item_params
    params.require(:item).permit(
    :name,
    :content,
    :image,
    :address,
    :country,
    :country_code,
    :user_id,
    prices_attributes: [:price, :item_id, :user_id, :_destroy]
    )
   end
end