Ruby on rails 4 using filterrific to filter based on checkbox -

i using filterrific gem in rails app filter result, have events filtered based on options code follows

event.rb

filterrific :default_filter_params => { :sorted_by => 'created_at_desc' },               :available_filters => %w[                 sorted_by                 search_query                 with_category_id                 with_area               ]   # default will_paginate    self.per_page = 9  scope :with_category_id, lambda { |category_ids|                           where(category_id: [*category_ids])                         } 

events_controller.rb

def index   @filterrific = initialize_filterrific(         event,         params[:filterrific],         :select_options => {              sorted_by: event.options_for_sorted_by,              with_category_id: category.options_for_select          }     ) or return     @events = @filterrific.find.paginate(page: params[:page], per_page: 6).where(is_job: false)     respond_to |format|       format.html       format.js     end end 

index.html.erb

<%= form_for_filterrific @filterrific, :class => 'col s12' |f| %>            <%= render_filterrific_spinner %>           <%= f.hidden_field :source , :value => 'event' %>           <div class="col s12 m3 ">             <div class="filter-container">              <li>                   <%= f.select(                                   :with_category_id,                                   @filterrific.select_options[:with_category_id],                                   { include_blank: ' ' },                                   class: 'select-filter'                           ) %>                        <label>select category</label>                  </li>              </div>             <%= link_to(                         'reset filters',                         reset_filterrific_url,                 ) %>           </div>       <% end %>  <%= render(                                                  partial: 'events/list',                                           ) %> 

index.js.erb

<% js = escape_javascript(   render(partial: 'events/list') ) %> $("#filterrific_results").html("<%= js %>"); $('#filterrific_results').load(document.url +  ' #filterrific_results'); 

_list.html.erb

<div id="filterrific_results"> <% @events.each |event| %> <%= link_to event.name, company_event_path(event.company.id, event.id) %>  <% end %>  </div> 

so doing here filtered events based on category select box want add feature in select box select box must contain checkbox elements can filter multiple category result, when check on 1 category filter result single category , when click category filter result category , previous category checked

would great fix , thankx in advance

you can use multiple: true, this:

<%= f.select(                                   :with_category_id,                                   @filterrific.select_options[:with_category_id],                                   { include_blank: ' ' },                                   { multiple: true, class: 'select-filter'}                           ) %>