ruby-on-rails – Rails 3 – 嵌套表单和默认值

我正在尝试创建包含rails中另一个模型的表单.我使用accepts_nested_attibutes完成了这项工作,并且它运行良好.问题是我在该表中有一个额外的字段记录每个注释的用户名,我不确定如何在创建新注释时插入该信息.应用程序控制器使用“current_user”方法提供用户名.

问候,
凯尔

评论模型

class Comment < ActiveRecord::Base
     belongs_to :post
     before_save :set_username

    private
     def set_username
      self.created_by = current_user
     end
    end

应用程序控制器(这只是一个沙盒应用程序所以我只是在方法中放入一个字符串)

class ApplicationController < ActionController::Base
  protect_from_forgery
  helper_method :current_user

  def current_user
    "FName LName"
  end

end

显示视图

<p id="notice"><%= notice %></p>
<p>
  <b>Title:</b>
  <%= @post.title %>
</p>
<div id="show_comments"><%= render 'comments' %></div>
<div id="add_comments">
    Add Comment
    <%= form_for @post,:url => {:action => 'update',:id => @post.id},:html => { :'data-type' => 'html',:id => 'create_comment_form' } do |f| %>
        <%= f.fields_for :comments,@new_comment do |comment_fields| %>
            <%= comment_fields.text_area :content %>
        <%end%>
      <div class="validation-error"></div>
      <%= f.submit %>
    <% end %>
</div>

后控制器

def update
    @post = Post.find(params[:id])
    respond_to do |format|
      if @post.update_attributes(params[:post])
        @comments = @post.comments.all
        format.html { redirect_to({:action => :show,:notice => 'Post was successfully created.') }
        format.xml  { render :xml => @post,:status => :created,:location => @post }
      else
        format.html { render :action => "new" }
        format.xml  { render :xml => @post.errors,:status => :unprocessable_entity }
      end
    end
  end

def update
  @post = Post.find(params[:id])
  @post.attributes = params[:post]
  @post.comments.each do |comment|
    comment.created_by = current_user if comment.new_record?
  end
  respond_to do |format|
    if @post.save
      @comments = @post.comments.all
      format.html { redirect_to({:action => :show,:notice => 'Post was successfully created.') }
      format.xml  { render :xml => @post,:location => @post }
    else
      format.html { render :action => "new" }
      format.xml  { render :xml => @post.errors,:status => :unprocessable_entity }
    end
  end
end