我正在尝试使用嵌套表单在创建歌曲时为歌曲添加类别标签。目前,每当我提交表单时,它都会抛出一个质量分配错误,尽管事实上我已经放入了我认为正确的属性可访问特征。显然我在某个地方出了问题所以如果有人能为我指出这一点会很棒。 表格是:
<%= nested_form_for(@song) do |f| %>
...
<%= f.fields_for(@song.categorizations.build) do |cat| %>
<%= cat.label :category_id, "TAG" %>
<%= cat.select :category_id, options_for_select(Category.all.collect {|c| [ c.tag, c.id ] },
{ :include_blank => true }), prompt: "" %>
<%end%>
<%= f.submit "Save" %>
<% end %>
这里的相关模型是:
class Song < ActiveRecord::Base
attr_accessible :artist, :title, :categorizations_attributes
has_many :categorizations, dependent: :destroy
has_many :categories, through: :categorizations
accepts_nested_attributes_for :categorizations
歌曲控制器如下所示:
def create
@song = Song.new(params[:song])
if @song.save
flash[:success] = "Song successfully added to library"
redirect_to @song
else
#FAIL!
render 'new'
end
end
最后引发的错误是:
ActiveModel::MassAssignmentSecurity::Error in SongsController#create
Can't mass-assign protected attributes: categorization
提前感谢您的帮助!