Rendering one models 'edit form' in anothers 'index view' - ruby-on-rails

Question

I have two models, Teams and Players. On the teams index page I have a list of players that aren't assigned to a team. I'm trying to make a button so that I can click on one of the players with no team and have the 'edit form' of this player show up on the team index page.
This is my current team#index:
= link_to 'New Team', new_team_path
= link_to 'New Player', new_player_path
#teamLists
- #teams.each do |team|
.team
.teamtitle
.teamname
= link_to truncate(team.name, length: 18), edit_team_path(team)
.teammoney
= number_to_currency(team.adjust_money, precision: 0)
%table
%tr.tableheading
%th.namecolumn Player
%th.poscolumn Pos
%th.pricecolumn $
-team.players.each do |player|
%tr
%td.namecolumn= player.name
%td.poscolumn= player.position
%td.pricecolumn= player.price
-(1..(10-team.players.length)).each do |x|
%tr
%td ---
=render template: 'players/edit'
=render 'players/playerlist'
and this is my player#edit
%h1 Nominated Player
= render 'players/form'
= link_to 'Show', #player
= link_to 'Back', players_path
and the players/form
<%= form_for(#player) do |f| %>
<% if #player.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#player.errors.count, "error") %> prohibited this player from being saved:</h2>
<ul>
<% #player.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.label :name %><br />
<%= f.text_field :name %>
</div>
<div class="field">
<%= f.label :position %><br />
<%= f.text_field :position %>
</div>
<div class="field">
<%= f.label :price %><br />
<%= f.number_field :price %>
</div>
<div class="field">
<%= f.label :team_id %><br />
<%= f.select :team_id, Team.all.map { |team| [team.name, team.id] }, { :include_blank => true } %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
At the moment I get this error 'undefined method `model_name' for NilClass:Class' I think its because the form doesn't have access to #player which is defined in the players edit action. Is there a way I can get this to work somehow?

Answer 1

You can reference any partial from another view page, and that's fine. However, like in your case, if that partial you require needs some instance variables (like #player) you'll have to either: A) declare it in the controller of Teams, or B) pass it in to the partial.
So for A), in your Teams controller for action index, just add #player = Player.new or whatever you need it to be.
For B), do:
render :partial => "my_partial", :locals => {:player => Player.new}