Rails handling a list of collection_select - html

Question

Pretty new to Ruby, but I'm working on a website for editing information on bus routes for a larger system. The DB has Route separate from it's list of stops, Trips. I'm trying to make the list of stops for each Route easily editable with a list of collection_select forms, where each presents a list of all of the stops to choose from. That was easy with the code below in
routes/_form.html.erb
<!-- handles the list of stops -->
<div class="stops_list" id="stops_list">
<%= f.label "Stops", :class => 'control-label'%>
<% params.merge!(:trips => {}) %>
<% puts params.inspect %>
<% trips = Trip.where('route_id = ?', #route.id).order('trips.order ASC') %>
<% #trips.each do |trip| %>
<%divId = 'stop'+trip[0].to_s %>
<div class="controls" id= <%= divId %>>
<%= f.label trip[0].to_s + '.', :class => 'control-label'%>
<%= collection_select params[:trips], trip[0].to_s, Stop.order('name ASC').all, :id, :name, {:selected => #trips[trip[0]]} %>
</div>
<% end %>
And then I update the proper tables in the DB from the routes_controller based on the data in params. I'd also like to be able to add and remove stops. I tried adding a 'remove stop' button, as below,
<%= button_to_function 'Remove stop',
'if(confirm("Really?")) {
$("#stops_list div").last().remove();
$.get("/routes/removeLastStop/'+(#route.id.to_s)+'");
}'%>
and it removes the proper collection_select form, but I then have to remove the stop from params. I tried doing an ajax call, as you can see, but then I have a new instance of the routes_controller, and the params I want to change is inaccessible. I'm not sure if I just set up the stops list wrong in the first place, or if there's a quick fix, but can anyone more experienced point me in the right direction?
EDIT:
Here's the entire form; it's pretty simple until you reach the area I've added
<%= form_for #route, :html => { :class => 'form-horizontal' } do |f| %>
<div class="control-group">
<%= f.label :name, :class => 'control-label' %>
<div class="controls">
<%= f.text_field :name, :class => 'text_field' %>
</div>
</div>
<div class="control-group">
<%= f.label :longname, :class => 'control-label' %>
<div class="controls">
<%= f.text_field :longname, :class => 'text_field' %>
</div>
</div>
<div class="control-group">
<%= f.label :color, :class => 'control-label' %>
<div class="controls">
<%= f.text_field :color, :class => 'text_field' %>
</div>
</div>
<div class="control-group">
<%= f.label :shape, 'Shape (KML file)', :class => 'control-label' %>
<div class="controls">
<%= f.file_field :shape, :class => 'file_field' %>
</div>
</div>
<div class="control-group">
<%= f.label :enabled, :class => 'control-label' %>
<div class="controls">
<%= f.check_box :enabled, :class => 'checkbox' %>
</div>
</div>
<!-- handles the list of stops -->
<div class="stops_list" id="stops_list">
<%= f.label "Stops", :class => 'control-label'%>
<% params.merge!(:trips => {}) %>
<% puts params.inspect %>
<% trips = Trip.where('route_id = ?', #route.id).order('trips.order ASC') %>
<% #trips.each do |trip| %>
<%divId = 'stop'+trip[0].to_s %>
<div class="controls" id= <%= divId %>>
<%= f.label trip[0].to_s + '.', :class => 'control-label'%>
<%= collection_select params[:trips], trip[0].to_s, Stop.order('name ASC').all, :id, :name, {:selected => #trips[trip[0]]} %>
</div>
<% end %>
<%= button_to_function 'Remove stop',
'if(confirm("Really?")) {
$("#stops_list div").last().remove();
$.get("/routes/removeLastStop/'+(#route.id.to_s)+'");
}'%>
</div>
<!-- adds submit button -->
<div class="form-actions">
<%= f.submit nil, :class => 'btn btn-primary' %>
<%= link_to t('.cancel', :default => t("helpers.links.cancel")),
routes_path, :class => 'btn' %>
</div>
<% end %>

Answer 1

Firstly you can add to Route class:
class Route < ActiveRecord::Base
has_many :trips
end
Firstly i'd like to advise you using decorators, inserting Models in Views is not the best practice.
Secondly you can use gem 'draper' and in RouteDecorator class you can add functions for creating something you want to use or display.
Thirdly you'd better use:
<div class="controls" id="stop<%= trip[0].to_s %>">
Forthly it would be better to use paths in REST-style:
/routes/2/stop/remove
/routes/2/stop/add
Fifthly can you give code of all form?
Probably we need to refactor it to look better and be easier for understanding.