ruby-on-rails - 模态表单无法正常工作

Question

我的模态正在工作（意味着当我单击按钮时它会出现）但表单没有出现，我在索引操作中有这个模态所以我添加了<% @entries.each do |entry| %>，没有它我是aving undefined methodNilClass:Class 的模型名称，有什么建议吗？

<%= link_to "Assign", "#saturday-one", :class => "btn btn-primary", "data-toggle" => "modal" %>
<div class="modal hide fade" id="saturday-one">
  <div class="modal-header">
    <h3 id="myModalLabel">Time Table</h3>
  </div>
  <div class="modal-body">
    <% @entries.each do |entry| %>
    <%= simple_form_for(entry) do |f| %>
    <%= f.association :subject, as: :select, label: 'Select Subject' %>
    <%= f.association :employee, as: :select, label: 'Assign Employee' %>
    <%= f.submit %>
    <% end %>
    <% end %>
  </div>
  <div class="modal-footer">
    <button aria-hidden="true" class="btn btn-info" data-dismiss="modal">Done</button>
  </div>
</div>

time_table_entries_controller.rb

class TimeTableEntriesController < ApplicationController
    def index
        @entries = TimeTableEntry.all
    end

    def show
        @entry = TimeTableEntry.find(params[:id])
    end

    def new
        @entry = TimeTableEntry.new
    end

    def create
        @entry = TimeTableEntry.new(params[:time_table])
        if @entry.save
            redirect_to time_table_entries_url , notice: 'Time table Entries saved'
        else
            render :new
        end
    end

    def edit
        @entry = TimeTableEntry.find(params[:id])
    end

    def update
        @entry = TimeTableEntry.find(params[:id])
        if @entry.update_attributes(params[:time_table])
            redirect_to time_table_entries_url, notice: 'TimeTableEntry Updated.'
        else
            render :edit
        end
    end
end