Undefined Method Error When Rendering Partial - ruby-on-rails

Question

So, I entirely understand why one would normally receive an undefined method error, however, I am unsure why it is happening this particular time.
I have a partial:
submissions/_submission.html.erb
<div class="pure-u-1-2 rounded">
<%= link_to submission do %>
<div class="rounded" style="background-color: #B81324; color: #E6E6E6; margin: 10px; padding:5px;">
<div class="clear">Project: <%= submission.project.title %></div>
<div class="clear">Submitted By: <%= submission.submitter.username %></div>
<div class="clear">Amount: $<%= submission.price %></div>
<div class="clear">Description: <%= submission.description %></div>
</div>
<% end %>
</div>
This partial is used twice in my dashboard/index.html.erb
Once to render a collection of received submissions and again to render a collection of sent submissions:
dashboards/index.html.erb
<% if #received_submissions.length > 0 %>
<div class="pure-u-1" id="projects"><h3 class="red">Final Tracks Received (<%= #received_submissions.length %>)</h3>
<%= render :partial => :submission, :collection => #received_submissions %>
</div>
<% end %>
<% if #sent_submissions.length != 0 %>
<div class="pure-u-1" id="projects"><h3 class="red">Final Tracks Sent (<%= #sent_submissions.length %>)</h3>
<%= render :partial => :submission, :collection => #sent_submissions %>
</div>
<% end %>
However, rendering the received submissions works without ailment, and rendering the sent submissions errors out with:
undefined method `submissions' for #<PlayerProject:0x000001052730e8>
Here is the dashboards_controller also, just in case:
class DashboardsController < ApplicationController
before_filter :authenticate_user!
def index
#compact = current_user.projects.where.not(status: ['Deleted','Closed']).order("id desc")
#projects = current_user.projects.where.not(status: ['Deleted','Closed']).order("id desc")
#received_messages = current_user.received_messages
#received_submissions = current_user.projects.collect{|p| p.submissions }.flatten
#player = current_user.player_projects.collect{|pp| pp.project}
#sent_submissions = current_user.player_projects.collect{|ps| ps.submissions }.flatten
end
end
models/player_project.rb'
class PlayerProject < ActiveRecord::Base
belongs_to :project
belongs_to :player, :class_name => "User"
end
models/submission.rb
class Submission < ActiveRecord::Base
belongs_to :submitter, :class_name => "User"
belongs_to :recipient, :class_name => "User"
belongs_to :project
validates :amount_in_cents, :presence => true, length: { minimum: 2, :message => " must be more than $0" }
validates :description, :presence => { :message => " cannot be blank" }
validates :final_track_url, :presence => { :message => " Required" }
def price
sprintf "%.2f", (self.amount_in_cents.to_f/100.0)
end
def price=(val)
self.amount_in_cents = (val.to_f*100.0).to_i
end
def paid?
!!self.paypal_confirmation
end
end

Answer 1

I think your error will be model-level:
undefined method `submissions' for #<PlayerProject:0x000001052730e8>
Association
This typically suggests you don't have a particular association set up (I.E you're calling #model.x when x is not defined):
#sent_submissions = current_user.player_projects.collect{|ps| ps.submissions }.flatten
Although your player_projects is defined, I think your submissions attribute / association does not exist. Besides, you can use the pluck method to help this: current_user.player_projects.pluck(:submissions)
Firstly, do you have the submissions attribute in your table?
Secondly, if you don't, what are you trying to achieve with it? You don't typically have a plural column in your table (denotes multiple data stores). I would use an association on a join-model

Answer 2

Try this
<%= render "submission", :collection => #sent_submissions %>