我跟隨此屏幕截圖製作嵌套模型表單。 http://railscasts.com/episodes/196-nested-model-form-part-1嵌套表單錯誤 - ArgumentError(參數的錯誤數目(0代表1)):
現在,我想我的應用程序包含這樣一個嵌套的模型窗體,但我收到了一個參數錯誤(錯誤數量的參數(0爲1))。
我似乎無法弄清楚我錯了什麼地方,想尋求一些建議,我可以嘗試什麼以及爲什麼會發生一些錯誤。
錯誤發生在主題模型中的這一行上。
has_many :lessons, :dependent => destroy
的其他相關的代碼:
主題控制器:
def new
@subject = Subject.new
#3 times one for lecture one for lab one for tut.
3.times{@subject.lessons.build}
respond_to do |format|
format.html # new.html.erb
format.json { render json: @subject }
format.js
end
end
物體模型
class Subject < ActiveRecord::Base
has_many :lessons, :dependent => destroy
attr_accessible :lesson_attributes, :acad_unit, :cohort_size, :discipline, :remarks, :subject_code, :subject_name, :year_of_study
accepts_nested_attributes_for :lessons, :reject_if => lambda { |a| a[:lesson_type].blank? }, :allow_destroy => true
end
課模型
class Lesson < ActiveRecord::Base
belongs_to :subject
attr_accessible :frequency, :lesson_type, :no_of_lesson, :possible_venues
end
_form.html.erb
<%= form_for(@subject,:remote=>true) do |f| %>
<% if @subject.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(@subject.errors.count, "error") %> prohibited this subject from being saved:</h2>
<ul>
<% @subject.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.label :subject_code %><br />
<%= f.text_field :subject_code %>
</div>
<div class="field">
<%= f.label :subject_name %><br />
<%= f.text_field :subject_name %>
</div>
<div class="field">
<%= f.label :year_of_study %><br />
<%= f.text_field :year_of_study %>
</div>
<div class="field">
<%= f.label :discipline %><br />
<%= f.text_field :discipline %>
</div>
<div class="field">
<%= f.label :acad_unit %><br />
<%= f.text_field :acad_unit %>
</div>
<div class="field">
<%= f.label :cohort_size %><br />
<%= f.text_field :cohort_size %>
</div>
<div class="field">
<%= f.label :remarks %><br />
<%= f.text_field :remarks %>
</div>
<ol>
<%= f.fields_for :lessons do |builder| %>
<%= render "lesson_fields", :f => builder %>
<% end %>
</ol>
<% end %>
_lesson_fields.html.erb
<p>
<div class="field">
<%= f.label :lesson_type %><br />
<%= f.text_field :lesson_type %>
</div>
<div class="field">
<%= f.label :no_of_lesson %><br />
<%= f.text_field :no_of_lesson %>
</div>
<div class="field">
<%= f.label :frequency %><br />
<%= f.text_field :frequency %>
</div>
<div class="field">
<%= f.label :possible_venues %><br />
<%= f.text_field :possible_venues %>
</div>
</p>
錯誤在哪個文件,什麼行...從你的stacktrace看到.. –
This line:has_many:lessons,:dependent => destroy –
這是完整的堆棧跟蹤。 ArgumentError(錯誤的參數數量(0代表1)): app/models/subject.rb:2:in <' app/models/subject.rb:1:in <' app/controllers/subjects_controller.rb:1:在' –