HABTM Problem

Hi All,

I have a form that is creating a ticket model. I am trying to allow
the user to assign employee's to this newly created ticket model. I
followed the complex form's railscast, which helped a lot it but it
appears the screencast is for creating two new models, instead of just
creating one model and linking an existing model to it. My problem is
I am just trying to assign employee's to the ticket model and not
create two new models.

This is the I have so far, which is giving me no errors, it is just
not putting any new data into my employees_tickets table.

TicketsController

class TicketsController < ApplicationController
layout 'global'
  def new
    @employees = Employee.find(:all)
    @ticket = Ticket.new
    @ticket.employees.build
  end

  def create
    @ticket = Ticket.new(params[:ticket])
    if @ticket.save
      flash[:notice] = "Successfully created ticket."
      redirect_to :action => "list", :controller => "workorders"
    else
      render :action => 'new'
    end
  end
end

Ticket Model
class Ticket < ActiveRecord::Base
  has_and_belongs_to_many :employees
end

Employee Model
class Employee < ActiveRecord::Base
  has_and_belongs_to_many :tickets
end

Create Ticket new.rhtml

<h1>Create Dispatch Ticket</h1>

<% form_for :ticket, :url => { :action => :create } do |form| %>
<p>
<label class="inputlabel">Address</label>
<%= text_field :ticket, :address %>
</p>

<p>
<label class="inputlabel">City</label>
<%= text_field :ticket, :city %>
</p>

<h2>Employees</h2>

<% for employee in @ticket.employees %>
  <% fields_for "ticket.employee", employee do |employee_form| %>
    <table style="width: 200px">
      <% for employee in @employees %>
        <tr>
          <td><%= employee.name %></td><td><%= employee_form.check_box :id
%></td>
        </tr>
      <% end %>
    </table>
  <% end %>
<% end %>

<br>
<%= submit_tag "Create", :class => "submit" %>

<% end if @ticket.new_record? %>

I tried simplifying things a bit but no luck either.

View:

<table style="width: 200px">
<% for employee in @employees %>
<tr>
  <td><%= employee.name %></td><td><%= check_box_tag
("ticket[employee_ids][]", employee.id) %></td>
</tr>
<% end %>
</table>

Controller:
class TicketsController < ApplicationController
layout 'global'
  def new
    @employees = Employee.find(:all)
    @ticket = Ticket.new
  end

  def create
    @ticket = Ticket.new(params[:ticket])
    @ticket.employees = Employee.find(@params[:employee_ids])
    if @ticket.save
      flash[:notice] = "Successfully created ticket."
      redirect_to :action => "list", :controller => "workorders"
    else
      render :action => 'new'
    end
  end

Error:
NoMethodError in TicketsController#create

You have a nil object when you didn't expect it!
You might have expected an instance of ActiveRecord::Base.
The error occurred while evaluating nil.[]

Recently I was implementing PDF generation for a project utilizing the fantastic library Prince XML (http://www.princexml.com). I came across a blog article with a basic library and helper set for Prince (http://sublog.subimage.com/articles/2007/05/29/html-css-to-pdf-using-ruby-on-rails), which provided a great basis. I wanted to make something a little more generalized and in-keeping the Rails Way, so I have created 'Princely', a simple wrapper utilizing much of the code from the SubImage library but giving it better helpers and pluginizing its inclusion.

== Installation ==

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script/install plugin http://svn.intridea.com/svn/public/princely

You are now ready to get started using Princely to generate PDF. Note that Princely is only compatible with Rails >= 2.0

== Usage ==

Princely uses the MimeTypes and respond_to blocks from Rails 2.0 to add PDF as a render option and a format. Because of this, it's incredibly easy to implement a PDF! Simply make your XHTML or XML template and use pdf as the format (e.g. show.pdf.erb), then add code similar to this in your controller:

class PagesController < ApplicationController
   def show
     respond_to do |format|
       format.html
       format.pdf {
         render :pdf => @page.pdf_name,
                :template => "show.pdf.erb", # not required, shown for example
                :layout => false # not required
       }
     end
   end
end

And that's all there is to it! If you add a .pdf to your properly routed path, you should be presented with a PDF version of the page generated by Prince. The README (http://svn.intridea.com/svn/public/princely/README) has more detailed usage information.

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