Rails form creating empty object - nested resource
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Looked at a number of resources and can't seem to figure this out.

I am working on a messaging system based on this code by BinaryMuse:

https://github.com/BinaryMuse/so_association_expirement/compare/53f2263...master

It doesn't have a respond feature, so I'm trying to build it.

I added the following code to the UserConversations controller:

	def update
		@user = User.find params[:user_id]
		@conversation = UserConversation.find params[:id]
		@conversation.user = current_user
		@message = @conversation.messages.build
		@message.conversation_id = @conversation
		@message.save
		redirect_to user_conversation_path(current_user, @conversation)
	end

And the following to the UserConversations#show view:

    <%= form_for(@conversation) do |f| %>
	<%= f.fields_for :messages do |m| %>
		<div>
			<%= m.label :body %><br />
			<%= m.text_area :body %>
		</div>
	<% end %>
    <%= f.submit %>
<% end %>

With what I have, a new message with the correct conversation_id is created. However, it has no body or user_id attached to it.

Any ideas what I'm doing wrong? 

Thanks in advance for your help!
