Re: [mongoid] recursively_embeds_many example needed

[Durran Jordan]

You don't need any second model, just add the macro, and remove the parent field:

class Musicstyle
  include Mongoid::Document
  field :musicstyle, type: String
  recursively_embeds_many
end

However there won't be any auto-setting of the parent since we're in an embedded situation, so your controller or model needs to set it... So if this was you creating a new
music style then the create action might look like:

parent = Musicstyle.find(params[:musicstyle].delete(:parent))
parent.child_musicstyles.create(params[:musicstyle])

You can see in the source, the macro is a convenience for an embeds_many/embedded_in pair:

https://github.com/mongoid/mongoid/blob/master/lib/mongoid/relations/cyclic.rb#L16

2012/7/3 Jan Jezek <global...@gmail.com>

Hi there,

sitting now since hours to figure out how to use the "recursively_embeds_many" function.

Do I need a second model like musicstyle_tree?

I am quite new to mongoid (and also rails).

My model looks like this.

class Musicstyle
  include Mongoid::Document

  field :musicstyle, type: String
  field :parent

end

my form contains this:

    <div class="field">
        <%= f.label :parent %>
        <%= f.select :parent,
                     Musicstyle.all.map { |m| [m.musicstyle, m._id] },
                     {:include_blank => "Select a parent (if needed)"} %>
    </div>

Is this the right approach?

Please help me!

many thanks

[Jan Jezek]

I (think) I got it working now:

MODEL

class Musicstyle

  include Mongoid::Document

 field :title, type: String

  recursively_embeds_many

end

CONTROLLER

def new

    @musicstyle = Musicstyle.new

    @all_musicstyles = Musicstyle.all

end

def create

    if params[:musicstyle][:parent_musicstyle]

      parent = Musicstyle.find(params[:musicstyle].delete(:parent_musicstyle))

      parent.child_musicstyles.create(params[:musicstyle])

    end

    @musicstyle = Musicstyle.new(params[:musicstyle])

end

VIEW

   <% if @all_musicstyles %>

        <div class="field">

            <%= f.label :parent_musicstyle %>

            <%= f.collection_select( :parent_musicstyle, @all_musicstyles, :_id, :title) %>

        </div>

    <% end %>

Results: (see attached screenshot)

- House

-- Ibiza House

- Ibiza House

-- Child Progressive House

- Progressive House 

hope this helps someone...

regards

:-)

[Jan Jezek]

erm, I am not really got it working... 

I got a 

undefined method `reflect_on_association' for "4ff47aff34257be005000006":String

error

Sorry Mate, please help me out!

(working since 2 days now on that "simple thing", maybe I am got blind)