Rails habtm嵌套选择在编辑时没有正确的选择值

时间:2012-08-16 18:40:40

标签: ruby-on-rails select nested has-and-belongs-to-many selected

我的RoR项目中有以下模型:  范围和project_scopes。

项目has_many :scopes, through: :project_scopes。同时投射accepts_nested_attributes_for :project_scopes

我通过几个选择将范围添加到项目中:

项目/ _form.html.haml

= form_for(@project) do |f|
  = f.fields_for :project_scopes do |builder|
    = render 'project_scope_fields', f: builder
  = link_to_add_fields 'Add scopes', f, :project_scopes

项目/ project_scope_fields.html.haml

= f.select :scope_id, options_from_collection_for_select(@scopes, "id", "name"), {include_blank: true, class: "project_scopes"}
= f.hidden_field :_destroy

这可以成功创建包含所有范围的项目。当我单击编辑时,它会呈现相同的表单并显示所有范围选择,但它们没有正确的选定值。

我该如何解决这个问题?

2 个答案:

答案 0 :(得分:4)

查看options_from_collection_for_select的文档:它需要4个参数,最后一个是选定的选项。你没有提供。试试这个:

= f.select :scope_id, options_from_collection_for_select(@scopes, "id", "name", @project.scope)

或只是使用collection_select帮助器:

= f.collection_select(:scope_id, @scopes, :id, :name)

答案 1 :(得分:1)

尝试以下(我假设您正确设置attr_accessible):

= f.select :scope_id, @scopes.map{|s| [s.name, s.id]}, {include_blank: true, class: "project_scopes"}

顺便说一下 - Scope可能不是最佳型号名称。