fohow_admin/app/models/balance_promotion.rb

class BalancePromotion < ActiveRecord::Base
    has_paper_trail
    self.table_name = "balance_promotions"
    validates :begin_time,:end_time,:name, presence: true
    validate :product_validation
    def product_validation
      if self.send_prod1 > 0
        prd1 = Product.where("id = ?", self.send_prod1).first
        if prd1.blank?
          self.errors.add(:send_prod1,"赠品1不存在，请重新填写。")
        end
      end
    end
    def send_prodcut1
      prd1 = Product.where("id = ?", self.send_prod1).first
      if !prd1.blank?
        return format("%s-%d",prd1.name,self.send_nums1)
      else
        return "--"
      end
    end

    def send_prodcut2
      prd1 = Product.where("id = ?", self.send_prod2).first
      if !prd1.blank?
        return format("%s-%d",prd1.name,self.send_nums2)
      else
        return "--"
      end
    end


    def send_prodcut3
      prd1 = Product.where("id = ?", self.send_prod3).first
      if !prd1.blank?
        return format("%s-%d",prd1.name,self.send_nums3)
      else
        return "--"
      end
    end

    
    rails_admin do 

        navigation_label '系统配置'
        weight -100

        list do 
          filters [:id,:name,:begin_time,:end_time]
          field :id
          field :name
          field :begin_time
          field :end_time
          field :min_total do
            label "充值最小金额（元）"
            formatted_value do # used in form views
              value.to_f / 100
            end
          end
          field :send_prodcut1
          field :send_prodcut2
          field :send_prodcut3
          field :cash do
            label "代办金（元）"
            formatted_value do # used in form views
              value.to_f / 100
            end
          end
          field :cent do
            label "积分（元）"
            formatted_value do # used in form views
              value.to_f / 100
            end
          end
          field :is_enable
          field :created_at
        end


        show do
          field :id      
          field :name
          field :begin_time
          field :end_time
      
          field :min_total do
            label "订单最小金额（元）"
            formatted_value do # used in form views
              value.to_f / 100
            end
          end
          field :send_prodcut1
          field :send_prodcut2
          field :send_prodcut3
          field :is_enable
          field :cash
          field :cent
          field :created_at
          field :created_at
          field :updated_at
        end

        edit do
          field :name
          field :begin_time
          field :end_time
          field :min_total
          field :send_prod1
          field :send_nums1
          field :send_prod2
          field :send_nums2
          field :send_prod3
          field :send_nums3
          field :cash
          field :cent
          field :is_enable
        end
    end
end