html - Creating links, with categories and filters, ActiveRecord::AssociationTypeMismatch in LinksController#create -

i stuck , need help. trying create links have categories , filters them. when i'm trying create new link categories , filter website show message i've inserted.

i inserted of code, if i'm missing please comment , add right away.

activerecord::associationtypemismatch in linkscontroller#create  level(#70251425229100) expected, got string(#70251404789620)    extracted source (around line #27):                      # post /links.json    def create      @link = current_user.links.build(link_params)        respond_to |format|        if @link.save    rails.root: /users/victorblomberg/startcode_co

activerecord (4.2.1) lib/active_record/associations/association.rb:216:in `raise_on_type_mismatch!'  activerecord (4.2.1) lib/active_record/associations/belongs_to_association.rb:12:in `replace'  activerecord (4.2.1) lib/active_record/associations/singular_association.rb:17:in `writer'  activerecord (4.2.1) lib/active_record/associations/builder/association.rb:123:in `level='  activerecord (4.2.1) lib/active_record/attribute_assignment.rb:54:in `public_send'  activerecord (4.2.1) lib/active_record/attribute_assignment.rb:54:in `_assign_attribute'  activerecord (4.2.1) lib/active_record/attribute_assignment.rb:41:in `block in assign_attributes'  actionpack (4.2.1) lib/action_controller/metal/strong_parameters.rb:183:in `each_pair'  actionpack (4.2.1) lib/action_controller/metal/strong_parameters.rb:183:in `each_pair'  activerecord (4.2.1) lib/active_record/attribute_assignment.rb:35:in `assign_attributes'  activerecord (4.2.1) lib/active_record/core.rb:559:in `init_attributes'  activerecord (4.2.1) lib/active_record/core.rb:281:in `initialize'  activerecord (4.2.1) lib/active_record/inheritance.rb:61:in `new'  activerecord (4.2.1) lib/active_record/inheritance.rb:61:in `new'  activerecord (4.2.1) lib/active_record/reflection.rb:131:in `build_association'  activerecord (4.2.1) lib/active_record/associations/association.rb:247:in `build_record'  activerecord (4.2.1) lib/active_record/associations/collection_association.rb:146:in `build'  activerecord (4.2.1) lib/active_record/associations/collection_proxy.rb:259:in `build'  app/controllers/links_controller.rb:27:in `create'  actionpack (4.2.1) lib/action_controller/metal/implicit_render.rb:4:in `send_action'  actionpack (4.2.1) lib/abstract_controller/base.rb:198:in `process_action'  actionpack (4.2.1) lib/action_controller/metal/rendering.rb:10:in `process_action'  actionpack (4.2.1) lib/abstract_controller/callbacks.rb:20:in `block in process_action'  activesupport (4.2.1) lib/active_support/callbacks.rb:117:in `call'  activesupport (4.2.1) lib/active_support/callbacks.rb:117:in `call'  activesupport (4.2.1) lib/active_support/callbacks.rb:555:in `block (2 levels) in compile'  activesupport (4.2.1) lib/active_support/callbacks.rb:505:in `call'  activesupport (4.2.1) lib/active_support/callbacks.rb:505:in `call'  activesupport (4.2.1) lib/active_support/callbacks.rb:92:in `_run_callbacks'  activesupport (4.2.1) lib/active_support/callbacks.rb:776:in `_run_process_action_callbacks'  activesupport (4.2.1) lib/active_support/callbacks.rb:81:in `run_callbacks'  actionpack (4.2.1) lib/abstract_controller/callbacks.rb:19:in `process_action'  actionpack (4.2.1) lib/action_controller/metal/rescue.rb:29:in `process_action'  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'  activesupport (4.2.1) lib/active_support/notifications.rb:164:in `block in instrument'  activesupport (4.2.1) lib/active_support/notifications/instrumenter.rb:20:in `instrument'  activesupport (4.2.1) lib/active_support/notifications.rb:164:in `instrument'  actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:30:in `process_action'  actionpack (4.2.1) lib/action_controller/metal/params_wrapper.rb:250:in `process_action'  activerecord (4.2.1) lib/active_record/railties/controller_runtime.rb:18:in `process_action'  actionpack (4.2.1) lib/abstract_controller/base.rb:137:in `process'  actionview (4.2.1) lib/action_view/rendering.rb:30:in `process'  actionpack (4.2.1) lib/action_controller/metal.rb:196:in `dispatch'  actionpack (4.2.1) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'  actionpack (4.2.1) lib/action_controller/metal.rb:237:in `block in action'  actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:74:in `call'  actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:74:in `dispatch'  actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:43:in `serve'  actionpack (4.2.1) lib/action_dispatch/journey/router.rb:43:in `block in serve'  actionpack (4.2.1) lib/action_dispatch/journey/router.rb:30:in `each'  actionpack (4.2.1) lib/action_dispatch/journey/router.rb:30:in `serve'  actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:819:in `call'  warden (1.2.3) lib/warden/manager.rb:35:in `block in call'  warden (1.2.3) lib/warden/manager.rb:34:in `catch'  warden (1.2.3) lib/warden/manager.rb:34:in `call'  rack (1.6.1) lib/rack/etag.rb:24:in `call'  rack (1.6.1) lib/rack/conditionalget.rb:38:in `call'  rack (1.6.1) lib/rack/head.rb:13:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/params_parser.rb:27:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/flash.rb:260:in `call'  rack (1.6.1) lib/rack/session/abstract/id.rb:225:in `context'  rack (1.6.1) lib/rack/session/abstract/id.rb:220:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/cookies.rb:560:in `call'  activerecord (4.2.1) lib/active_record/query_cache.rb:36:in `call'  activerecord (4.2.1) lib/active_record/connection_adapters/abstract/connection_pool.rb:649:in `call'  activerecord (4.2.1) lib/active_record/migration.rb:378:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'  activesupport (4.2.1) lib/active_support/callbacks.rb:88:in `call'  activesupport (4.2.1) lib/active_support/callbacks.rb:88:in `_run_callbacks'  activesupport (4.2.1) lib/active_support/callbacks.rb:776:in `_run_call_callbacks'  activesupport (4.2.1) lib/active_support/callbacks.rb:81:in `run_callbacks'  actionpack (4.2.1) lib/action_dispatch/middleware/callbacks.rb:27:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/reloader.rb:73:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/remote_ip.rb:78:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'  web-console (2.1.2) lib/web_console/middleware.rb:37:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'  railties (4.2.1) lib/rails/rack/logger.rb:38:in `call_app'  railties (4.2.1) lib/rails/rack/logger.rb:20:in `block in call'  activesupport (4.2.1) lib/active_support/tagged_logging.rb:68:in `block in tagged'  activesupport (4.2.1) lib/active_support/tagged_logging.rb:26:in `tagged'  activesupport (4.2.1) lib/active_support/tagged_logging.rb:68:in `tagged'  railties (4.2.1) lib/rails/rack/logger.rb:20:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/request_id.rb:21:in `call'  rack (1.6.1) lib/rack/methodoverride.rb:22:in `call'  rack (1.6.1) lib/rack/runtime.rb:18:in `call'  activesupport (4.2.1) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'  rack (1.6.1) lib/rack/lock.rb:17:in `call'  actionpack (4.2.1) lib/action_dispatch/middleware/static.rb:113:in `call'  rack (1.6.1) lib/rack/sendfile.rb:113:in `call'  railties (4.2.1) lib/rails/engine.rb:518:in `call'  railties (4.2.1) lib/rails/application.rb:164:in `call'  rack (1.6.1) lib/rack/lock.rb:17:in `call'  rack (1.6.1) lib/rack/content_length.rb:15:in `call'  rack (1.6.1) lib/rack/handler/webrick.rb:89:in `service'  /users/victorblomberg/.rbenv/versions/2.2.2/lib/ruby/2.2.0/webrick/httpserver.rb:138:in `service'  /users/victorblomberg/.rbenv/versions/2.2.2/lib/ruby/2.2.0/webrick/httpserver.rb:94:in `run'  /users/victorblomberg/.rbenv/versions/2.2.2/lib/ruby/2.2.0/webrick/server.rb:294:in `block in start_thread'

form.html.erb

<%= form_for(@link) |f| %>    <% if @link.errors.any? %>      <div id="error_explanation">        <h2><%= pluralize(@link.errors.count, "error") %> prohibited link being saved:</h2>          <ul>        <% @link.errors.full_messages.each |message| %>          <li><%= message %></li>        <% end %>        </ul>      </div>    <% end %>        <div class="form-group">        <%= f.collection_select :category_id, category.all, :id, :name, {promt: "choose category" }, input_html: { class: "dropdown-toggle" } %>        <%= f.collection_select :level_id, level.all, :id, :name, {promt: "choose level" }, input_html: { class: "dropdown-toggle" } %>          <div class="field">          <%= f.label :title %><br>          <%= f.text_field :title, class: "form-control" %>        </div>        <div class="field">          <%= f.label :subtitle %><br>          <%= f.text_field :subtitle, class: "form-control" %>        </div>        <div class="field">          <%= f.label :company %><br>          <%= f.text_field :company, class: "form-control" %>        </div>        <div class="field">          <%= f.label :websiteurl %><br>          <%= f.text_field :websiteurl, :value => "http://", class: "form-control" %>          </div>        <div class="field">          <%= f.label :linkcourse %><br>          <%= f.text_field :linkcourse, :value => "http://", class: "form-control" %>        </div>        <div class="field">          <%= f.label :time %><br>          <%= f.text_field :time, class: "form-control" %>        </div>        <div class="field">          <%= f.label :kind %><br>          <%= f.text_field :kind, class: "form-control" %>        </div>        <div class="field">          <%= f.label :level %><br>          <%= f.text_field :level, class: "form-control" %>        </div>        <div class="field">          <%= f.label :sharefacebook %><br>          <%= f.text_field :sharefacebook, :value => "http://", :target => '_blank', class: "form-control" %>        </div>        <div class="field">          <%= f.label :sharetwitter %><br>          <%= f.text_field :sharetwitter, :value => "http://", class: "form-control" %>        </div>        <div class="field">          <%= f.label :cost %><br>          <%= f.text_field :cost, class: "form-control" %>        </div>        <div class="actions">          <%= f.submit "submit", class: "btn btn-lg btn-primary"%>        </div>  </div>  <% end %>

user.rb

class user < activerecord::base    # include default devise modules. others available are:    # :confirmable, :lockable, :timeoutable , :omniauthable    devise :database_authenticatable, :registerable,           :recoverable, :rememberable, :trackable, :validatable      has_many :links  end

link.rb

class link < activerecord::base  	acts_as_votable  	belongs_to :user  	has_many :comments  	belongs_to :category  	belongs_to :level  end

level.rb

class level < activerecord::base  	has_many :links    end

category.rb

class category < activerecord::base  	has_many :links    end

links_controller.rb

class linkscontroller < applicationcontroller    before_action :set_link, only: [:show, :edit, :update, :destroy]    before_filter :authenticate_user!, except: [:index, :show]    # /links    # /links.json    def index      @links = link.all    end      # /links/1    # /links/1.json    def show    end      # /links/new    def new      @link = current_user.links.build    end      # /links/1/edit    def edit    end      # post /links    # post /links.json    def create      @link = current_user.links.build(link_params)        respond_to |format|        if @link.save          format.html { redirect_to @link, notice: 'link created.' }          format.json { render :show, status: :created, location: @link }        else          format.html { render :new }          format.json { render json: @link.errors, status: :unprocessable_entity }        end      end    end      # patch/put /links/1    # patch/put /links/1.json    def update      respond_to |format|        if @link.update(link_params)          format.html { redirect_to @link, notice: 'link updated.' }          format.json { render :show, status: :ok, location: @link }        else          format.html { render :edit }          format.json { render json: @link.errors, status: :unprocessable_entity }        end      end    end      # delete /links/1    # delete /links/1.json    def destroy      @link.destroy      respond_to |format|        format.html { redirect_to links_url, notice: 'link destroyed.' }        format.json { head :no_content }      end    end      def upvote       @link = link.find(params[:id])       @link.upvote_by current_user       redirect_to :back    end      def downvote       @link = link.find(params[:id])       @link.downvote_by current_user       redirect_to :back    end      private      # use callbacks share common setup or constraints between actions.      def set_link        @link = link.find(params[:id])      end        # never trust parameters scary internet, allow white list through.     def link_params      params.require(:link).permit(:title, :subtitle, :company, :websiteurl, :linkcourse, :time, :kind, :level, :sharefacebook, :sharetwitter, :cost, :level_id, :category_id)      end         end

try adding level_id , category_id in link_params

def link_params     params.require(:link).permit(:title, :subtitle, :company, :websiteurl, :linkcourse, :time, :kind, :level, :sharefacebook, :sharetwitter, :cost, :level_id, :category_id) end