Rails: Share variables between controller and view [duplicate] - ruby-on-rails

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Closed 10 years ago.
Possible Duplicate:
Passing only two variables between controller and view - best practice?
There is my action:
def list
#codes = Code.order("created_at")
#languages = Language.order('name').collect {|l| [l.name, l.coderay]}
end
There is my view(I removed some lines):
<% #codes.each do |code| %>
<div class="code">
<%= link_to code.title, :action => 'show', :id => code.id %>
<% if code.author %>
#<%= code.author %>
<% end %>
</div>
<% end %>
<%= render :partial => 'shared/error_messages', :locals => {:object => #code} %>
<%= form_for :code, :url => {:action => 'create' }, :html => {:multipart => true} do |f| %>
<%= f.text_field :title %><br />
<%= f.text_area :content %><br>
<%= f.select(:language, #languages, {:selected => 'text'}) %>
<%= f.text_field :author %><br>
<%= f.submit "Submit code" %>
<% end %>
There are 3 variables in it: #codes(list of posts), #code(current post, used in another action) and #languages.
My IDE writes:
At most two instance variables should be shared between controller and
view
This inspection warns if there are more than two instance
variables shared between a controller and a view. A controller should
only manage one instance variable, plus a second one for the
current_user variable.
Usually I share more variables between Controller and View(in PHP), sometimes 10+.
How it's done in Rails?

Answer 1

You can save an instance var by making languages a helper:
def languages
Language.order('name').collect {|l| [l.name, l.coderay]}
end

Answer 2

Its a guideline some developers follow some of the time.
But I would read up on Rails Routing a bit more. Understanding how Rails routing works should give you a better idea on how to structure your code.
http://guides.rubyonrails.org/routing.html
I modified your code a bit, not tested. But hopefully gives you some good ideas.
Controller:
def new
#code = Code.new
#codes = Code.order("created_at")
end
def create
#code = Code.new(params[:code])
if #code.save?
# Do your thing.
else
# render your :new action passing your #code variable
end
end
View:
<% #codes.each do |code| %>
<div class="code">
# Use Rails Routing - In console, type rake routes to get list of routes.
<%= link_to code.title, code_path(code.id) %> # example.
<% if code.author %>
<%= code.author %>
<% end %>
</div>
<% end %>
<%= render 'shared/error_messages', :object => #code %>
<%= form_for #code, :html => {:multipart => true} do |f| %>
<%= f.text_field :title %><br />
<%= f.text_area :content %><br>
# language_list = helper method.
<%= f.select(:language, language_list, {:selected => 'text'}) %>
<%= f.text_field :author %><br>
<%= f.submit "Submit code" %>
<% end %>