ruby-on-rails – 具有多态模型的嵌套表单

#app/models/goal.rb
  has_many :tasks,:as => :achievement
  has_many :milestones
  accepts_nested_attributes_for :tasks
  accepts_nested_attributes_for :milestones

#app/models/milestone.rb
  belongs_to :goal
  has_many :tasks,:as => :achievement

#app/models/task.rb
  belongs_to :achievement,:polymorphic => true

每当我用它的属性保存目标时,似乎任务模型对于它们属于什么成就类型感到困惑,导致每个里程碑任务被列为目标任务.我的表单,部分和控制器代码如下.

形成：

<%= nested_form_for @goal do |f| %>

  <%= render 'shared/error_messages',:object => f.object %>
  <%= render 'shared/goal_fields',:f => f %>

  <%= f.fields_for :milestones do |ff| %>
    <%= render 'shared/milestone_fields',:f => ff %>
  <% end %> 

  <%= f.fields_for :tasks do |ff| %>
    <%= render 'shared/task_fields',:f => ff %>
  <% end %>

  <%= f.link_to_add "Add Milestone",:milestones %>
  <%= f.link_to_add "Add Task",:tasks %>

  <%= f.submit %>

<% end %>

milestone_fields partial：

<%= f.label :content,"Milestone" %>
  <%= f.text_field :content %>

  <%= f.fields_for :tasks do |ff| %>
    <%= render 'shared/task_fields',:f => ff %>
  <% end %>

  <%= f.link_to_remove "Remove milestone" %>
  <%= f.link_to_add "Add Milestone Task",:tasks %>

task_fields partial：

<%= f.label :content,"Task" %>
  <%= f.text_field :content %>
  <%= f.link_to_remove "Remove Task" %>

目标控制器：

def new
  @goal = current_user.goals.new
end

def create
  @user = current_user
  @goal = @user.goals.build(params[:goal])
  if @goal.save
    flash[:success] = "Goal created!"
    redirect_to goals_path 
  else
    render 'new'
  end 
end

我尝试在f.fields_for代码旁边添加@ goal.milestones.build和@ goal.tasks.build,这似乎修复了它,但导致了其他问题,例如空白编辑表单(没有预先填充数据)并且里程碑和任务字段立即显示,而不是单击链接以显示空白字段.如果你无法解决它,有没有我可以支付其他程序员帮助解决这样的小问题的网站？我在这一点上很绝望.