ActiveAdmin forms with has_many - belongs_to relationships?

Question

I have the models Home and Photo, which have a has_many - belongs_to relationship (a polymorphic relationship, but I dont think that matters in this case). I am now setting up active admin and I would like admins to be able to add photos to homes from the homes form.

The photos are managed by the CarrierWave gem, which I dont know if will make the problem easier or harder.

How can I include form fields for a different model in the Active Admin Home form? Any experience doing something like this?

class Home < ActiveRecord::Base
  validates :name, :presence => true,
                     :length => { :maximum => 100 }
  validates :description, :presence => true      
  has_many :photos, :as => :photographable

end


class Photo < ActiveRecord::Base
    belongs_to :photographable, :polymorphic => true
    mount_uploader :image, ImageUploader
end

score 63 · Accepted Answer · edited May 23 '17 at 12:17

63

Try something like this in app/admin/home.rb:

form do |f|
  f.inputs "Details" do
    f.name
  end

  f.has_many :photos do |photo|
    photo.inputs "Photos" do
      photo.input :field_name 
      #repeat as necessary for all fields
    end
  end
end

Make sure to have this in your home model:

accepts_nested_attributes_for :photos

I modified this from another stack overflow question: How to use ActiveAdmin on models using has_many through association?

edited May 23 '17 at 12:17

Community

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answered Nov 07 '11 at 21:21

jfedick

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Thanks man, but as soon as I use f.has_many I get an error: undefined method `new_record?' for nil:NilClass – agente_secreto Nov 08 '11 at 14:53
Maybe it has anything to do with the polymorphic association? – agente_secreto Nov 08 '11 at 14:54
I tried using accepts_nested_attributes_for :photos in my Home model, but that doesnt work either. – agente_secreto Nov 08 '11 at 18:57
Ok, I did that last part wrong the first time around, but that was the remaining problem, so maybe you should add it to your answer. Thanks! – agente_secreto Nov 08 '11 at 19:24
4

I also get the undefined method 'new_record?' for nil:NilClass error. How did you solved it @agente_secreto? – Agis Sep 02 '12 at 00:58
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You need to add accepts_nested_attributes_for :children in your Parent model - that's how it solved – Ildar Jan 02 '13 at 11:17
@agente_secreto I updated my solution with the accepts_nested_attributes call. – jfedick Mar 07 '13 at 18:32
2

I had to do `f.input :name` rather than `f.name`. – ScottJShea Jun 28 '13 at 01:37
Also need to add `f.actions` as the last item in the `form` block to get the 'Create' and 'Cancel' buttons – tmimicus Jan 21 '14 at 22:49
Will the engine allow to update each photo's data separately without a whole page reload? – Малъ Скрылевъ May 23 '14 at 13:06
if I have a set of images and I want to select the values from them, how can I do it using forms? ex: I have a product and several categories when I create a new product I should be able to add multiple categories from a predefined list of categories. – rahulrvp Nov 27 '17 at 09:23

score 2 · Answer 2 · answered Mar 19 '15 at 17:42

You could try this:

form do |f|
  f.semantic_errors # shows errors on :base
  f.inputs          # builds an input field for every attribute

  f.inputs 'Photos' do
    f.has_many :photos, new_record: false do |p|
      p.input :field_name
      # or maybe even
      p.input :id, label: 'Photo Name', as: :select, collection: Photo.all
    end
  end

  f.actions         # adds the 'Submit' and 'Cancel' buttons  
end

Also, you can look at https://github.com/activeadmin/activeadmin/blob/master/docs/5-forms.md (See Nested Resources)

score 0 · Answer 3 · edited Oct 21 '12 at 06:07

0

I have a has_one model, like this:

f.has_many :addresses do |a|
  a.inputs "Address" do
    a.input :street  ... etc.

While this correctly reflects our associations for Address (which is a polymorphic model) using f.has_one fails. So I changed over to has_many and all's well. Except now we have to prevent our users from creating multiple addresses for the same entity.

edited Oct 21 '12 at 06:07

mu is too short

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answered May 28 '12 at 02:40

John Mount

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score 0 · Answer 4 · edited Jun 20 '20 at 09:12

0

I guess you are looking for a form for a nested model. Take a look at following railscasts.

http://railscasts.com/episodes/196-nested-model-form-part-1

http://railscasts.com/episodes/197-nested-model-form-part-2

I cannot tell you much about active_admin, but I think this should not make a difference in handling the nested model.

edited Jun 20 '20 at 09:12

Community

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answered Nov 07 '11 at 09:54

rangalo

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Great, I will check them out, railscasts are always very useful – agente_secreto Nov 07 '11 at 15:23

ActiveAdmin forms with has_many - belongs_to relationships?

4 Answers4