form_for save input values to session variables - ruby-on-rails

Question

I am trying to create a compare functionality for an index of schools. Currently I am using the following code which takes any checked school and adds it to the school_ids[] in the params.
In my gemfile:
gem 'will_paginate'
In my school's index.html.erb:
<%= form_tag compare_path, :method => 'get' do %>
<%= submit_tag "Compare" %>
<ul>
<% #schools.each do |school| %>
<li>
<%= check_box_tag'school_ids[]', school.id %>
<%= link_to school.name, school %><br>
<%= school.city %>, <%= school.state %>
</li>
<% end %>
</ul>
<% end %>
In my school controller I have:
def compare
#schools = School.find(params[:school_ids])
end
This works great as long as all of the check schools are on the same page. But since I'm using will_paginate to paginate the list of schools, if I change pages, the check boxes do not persist. I'm assuming I need to save to sessions somehow.

Answer 1

Do you mean you want to be able to add a check mark to a school A on page 1 of the index, go to page 2 of the index and add another check mark for school B, then submit the compare form and see schools A and B? If that's the case, then you're correct, you need to get the check boxes into the session. Attach a js click event, like
$('.checkbox_class').click(function(){
$.post('update_session_method', { school_id: $(this).val(), checked: $(this).is(:checked)]);
});
then add a controller method
def update_session_method
session[:school_ids] ||= []
if params[:checked]
session[:school_ids] << params[:school_id]
else
session[:school_ids].delete(params[:school_id])
end
end
then your compare method
def compare
#schools = School.find(params[:school_ids].merge(session[:school_ids] || []))
end