我在 Rails 应用程序中使用 Mailboxer ( https://github.com/ging/mailboxer ) gem 来处理用户之间的私人消息。根据文档，我= render mailbox.inbox用来显示登录用户的所有对话（消息）的列表。但是，该方法仅输出消息的主题。我需要显示邮件的发件人以及主题。如何编辑此输出以显示发件人姓名？
SQL 表显示发件人姓名未存储在对话表中，而是通过通知表中的通知表（一对多）。我尝试使用<%= conversation.notifications.sender_id %>，但出现以下错误：
NoMethodError in Conversations#index
undefined method `notifications' for nil:NilClass
为了显示对话的用户和主题，我可以添加什么到对话控制器和查看？
谢谢！
对话控制器：
class ConversationsController < ApplicationController
before_filter :authenticate_user!
helper_method :mailbox, :conversation
def create
recipient_emails = conversation_params(:recipients).split(',')
recipients = User.where(email: recipient_emails).all
conversation = current_user.
send_message(recipients, *conversation_params(:body, :subject)).conversation
redirect_to conversation
end
def reply
current_user.reply_to_conversation(conversation, *message_params(:body, :subject))
redirect_to conversation
end
def trash
conversation.move_to_trash(current_user)
redirect_to :conversations
end
def untrash
conversation.untrash(current_user)
redirect_to :conversations
end
private
def mailbox
@mailbox ||= current_user.mailbox
end
def conversation
@conversation ||= mailbox.conversations.find(params[:id])
end
def conversation_params(*keys)
fetch_params(:conversation, *keys)
end
def message_params(*keys)
fetch_params(:message, *keys)
end
def fetch_params(key, *subkeys)
params[key].instance_eval do
case subkeys.size
when 0 then self
when 1 then self[subkeys.first]
else subkeys.map{|k| self[k] }
end
end
end
end