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

Create Dispatch Ticket

<% form_for :ticket, :url => { :action => :create } do |form| %>

Address <%= text_field :ticket, :address %>

City <%= text_field :ticket, :city %>

Employees

<% for employee in @ticket.employees %>
<% fields_for “ticket.employee”, employee do |employee_form| %>


<% for employee in @employees %>



<% end %>
<%= employee.name %> <%= employee_form.check_box
:id
%>

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

<% end if @ticket.new_record? %>

I tried simplifying things a bit but no luck either.

View:

<% for employee in @employees %> <% end %>
<%= employee.name %> <%= check_box_tag ("ticket[employee_ids][]", employee.id) %>

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 ==

The first step is to download Prince (Prince - Download Prince 15.1)
and install it on your platform of choice (only Linux and Mac OS X
supported by the plugin at this time). Next, simply install the plugin:

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.

There is a Trac (http://trac.intridea.com/trac/public/) available for
any bugs or patches you might come across. Additionally you can
comment on this at the original blog post
(http://www.intridea.com/2007/12/20/announcing-princely-rails-prince-xml-pdf-wrapper
).