I have 3 tables, Activity, Activity_type and Itineraries. In activity type, I insert a new entry name => Testing => Example. In my activity, I can use the activity type I created earlier in my dropdown and type a location.
In creating a new itinerary there's a dropdown activity and user(who created the new itinerary and choose what activity for the specific itinerary) but it only shows the activity #1 and user #1. In my list and i think this is the reason why it only display the Activity #1 instead Testing.
Question:
1) In creating a new itinerary how can I change the activity #1 to the specific name?(example: In dropdown it should be Testing not Activity #1)
2)How can I display the name instead of an ID without the name column?
Activity table
activity_type_id
location_id
Itinerary table
title
created_by
Activity type table
name
description
NOTE: I also tried this below but nothing happened
Rails admin
config.model Itinerary do
list do
  field :title
  # field :schedule
  field :no_of_days
  field :activity
  field :user      
  # field :location      
  # field :activity_type
  # field :location_name
end
create do
  field :title    
end
object_label_method do 
    :activity_label_method
    end
  def activity_label_method
     "#{self.activity_type_id}" 
  end
end
Itinerary model
class Itinerary < ApplicationRecord
  belongs_to :user, foreign_key: :created_by
  belongs_to :activity
  has_many :activity_itineraries, foreign_key: :created_by
  validates :user, presence: true
  validates :title, presence: true, length: { maximum: 20 }
  validates :no_of_days, presence: true,
               :numericality => true
  def name
    activity_type.name
  end
end