我用的是：

gem 'rails', '~> 5.2'
gem 'notifications', '~> 0.6.0'
gem 'kaminari'

我的 notifications_controller.rb:

# notifications_controller.rb

module Notifications
  class NotificationsController < Notifications::ApplicationController
    def index
      @notifications = notifications.includes(:actor).order("id desc").page(params[:page])
      unread_ids = @notifications.reject(&:read?).select(&:id)
      Notification.read!(unread_ids)
      @notification_groups = @notifications.group_by { |note| note.created_at.to_date }
    end

    def clean
      notifications.delete_all
      redirect_to notifications_path
    end

    private

    def notifications
      raise "You need reqiure user login for /notifications page." unless current_user
      Notification.where(user_id: current_user.id)
    end
  end
end


# routs.tb 

mount Notifications::Engine, at: "notifications"

我的 index.html.erb:

# notifications/notifications/index.html.erb 的分页

<div class="paginationBox">
        <%= paginate @notifications,left:2,right:1,window: 1 %>
      </div>

我按照视频：https://ruby-china.org/topics/36891 做通知系统，现在别的功能都能正常实现，但是通知页面，不能分页显示。错误信息提示为：

NoMethodError - undefined method `total_pages' for #<Notification::ActiveRecord_Relation:0x00007fcfacae6dd8>:
  app/views/notifications/notifications/index.html.erb:33:in `_app_views_notifications_notifications_index_html_erb__2430601159943313679_70264929101860'

如果我修改notifications_controller.rb中index动作的 @notifications为@notifications = notifications.includes(:actor).order("id desc").page(params[:page]).per(10)也是出现同样的错误。

如果我修改通知页面的：index.html.erb为：

# notifications/notifications/index.html.erb 的分页

<div class="paginationBox">
        <%= paginate @notifications.page(params[:page]).per(10),left:2,right:1,window: 1 %>
      </div>

则不会分页显示。

请问下大家，我是哪里出现了错误，该怎么调整？谢谢大家。