Rails 5 - has_many through: association and select in view - ruby-on-rails

Question

How I can get selected values in select helper with has_many through: association and nested form?
app/models/team.rb
class Team < ApplicationRecord
has_many :team_users
has_many :users, through: :team_users
accepts_nested_attributes_for :team_users, allow_destroy: true, reject_if: proc { |a| a['user_id'].blank? }
end
app/models/user.rb
class User < ApplicationRecord
has_many :team_users
has_many :teams, through: :team_users
accepts_nested_attributes_for :team_users, :teams, allow_destroy: true
end
app/models/team_user.rb
class TeamUser < ApplicationRecord
belongs_to :team
belongs_to :user
accepts_nested_attributes_for :team, :user, allow_destroy: true
end
app/controllers/teams_controller.rb
class TeamsController < ApplicationController
before_action :set_team, only: [:show, :edit, :update, :destroy]
before_action :set_team_users, only: [:new, :edit]
before_action :set_new_team_user, only: [:new, :edit]
before_action :set_team_users_collection, only: [:new, :edit]
...
# GET /teams/1/edit
def edit
end
...
private
# Use callbacks to share common setup or constraints between actions.
def set_team
#team = Team.find(params[:id])
end
def set_team_users
#team_users = #team.team_users
end
def set_new_team_user
#new_team_user = #team.team_users.build
end
def set_team_users_collection
#team_users_collection = User.all.collect { |p| [ p.name, p.id ] }
end
def team_params
params.require(:team).permit(
:name,
:parent_id,
team_users_attributes: [:_destroy, :id, :user_id]
)
end
end
app/views/teams/_form.html.erb
<%= form_for(#team) do |f| %>
...
<% f.fields_for #team_users do |team_user_f| %>
<%= team_user_f.select(:user_id, #team_users_collection, { include_blank: true }, class: 'form-control custom-select', style: 'width:auto;') %>
<% end %>
...
<% end %>
This generates the following error:
undefined method 'user_id' for #<TeamUser::ActiveRecord_Associations_CollectionProxy:0x007f90a13a3f70>

Answer 1

I believe you may have your arguments wrong in the select method:
<%= team_user_f.select(:team_user, :user_id, #team_users_collection, { include_blank: true }, class: 'form-control custom-select', style: 'width:auto;') %>
See if that works