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One of the most amazing things about Ruby on Rails is how easy it is to create Active Record associations between models. We try to keep the same simple approach in Avo too.


It's important to set the inverse_of as often as possible to your model's association attribute.

Single Table Inheritance (STI)

When you have models that share behavior and fields with STI, Rails will cast the model as the final class no matter how you query it.

# app/models/user.rb
class User < ApplicationRecord

# app/models/super_user.rb
class SuperUser < User

# => [User, SuperUser]

For example, when you have two models, User and SuperUser with STI, when you call User.all, Rails will return an instance of User and an instance of SuperUser. That confuses Avo in producing the proper resource of User. That's why when you deal with STI, the final resource SuperUserResource should receive the underlying model_class so Avo knows which model it represents.

class SuperUserResource < Avo::BaseResource
  self.title = :name
  self.includes = []
  self.model_class = ::SuperUser

  field :id, as: :id
  field :name, as: :text

Add custom labels to the associations' pages

You might want to change the name that appears on the association page. For example, if you're displaying a team_members association, your users will default see Team members as the title, but you'd like to show them Members.

You can customize that using fields localization.

Custom label