ruby-on-rails - 带有 simple_form 的 Rails：使用 link_to_add 添加新表行

Question

我在通过单击 link_to_add 函数链接添加新表行时遇到问题。

Answer 1

因为我花了一些搜索和尝试错误才发现这里是我的解决方案。它的关键是使用 nathanvda 的cocoon gem（而不是ryanb的nested_form），它允许定义一个 jquery 选择器（称为data-association-insertion-node）在哪里插入新的字段集。在我的示例中，我使用了 HAML 和 Twitter Bootstrap 代码，但您可以轻松地将其替换为自己喜欢的代码。

/app/views/users/_form.html.haml：

= simple_form_for @user, :html => {:class => "form-horizontal"} do |f|
  = render "shared/error_messages", :target => @user
  .row-fluid
    .span12
      .fieldset
        = f.input :username, :label => "Username:", :placeholder => "Username"

        %table.table
          %thead
            %tr
              %th
                %i.icon-calendar
                Date
              %th
                %i.icon-pencil
                Description
              %th
                %i.icon-cog
                Action
          %tbody#user_events
            = f.simple_fields_for :user_events do |event|
              = render "user_event_fields", :f => event

        = link_to_add_association f, :user_events, :"data-association-insertion-node" => "tbody#user_events", :"data-association-insertion-method" => "append", :partial => "user_event_fields", :class => "btn" do
          %i.icon-plus
          Add new event

        %p.help-block
          %strong Please note:
          Events are only removed after confirming the changes with
          %span.label
            %i.icon-ok
            Update settings!

        = f.button :submit, :class => "btn" do
          %i.icon-ok
          Update settings!

/app/views/users/_user_event_fields.html.haml：

%tr.nested-fields
  %td= f.input_field :date, :as => :date_month_year, :class => "tooltip-bottom input-small", :rel => "tooltip", :title => "Date of event", :disabled => params[:action] == "show"
  %td= f.input_field :description, :placeholder => "Description", :class => "input-large tooltip-bottom", :rel => "tooltip", :title => "Description of event<br/>Use <strong>Markdown</strong> to format your text.", :disabled => params[:action] == "show"
  %td= f.input_field :label, :placeholder => "Label", :class => "input-medium tooltip-bottom", :rel => "tooltip", :title => "Label of event", :disabled => params[:action] == "show"
  %td= f.input_field :label_class, :collection => [["Green", "label-success"], ["Yellow", "label-warning"], ["Red", "label-important"], ["Blue", "label-info"], ["Black", "label-inverse"]], :include_blank => "Grey", :class => "input-small tooltip-bottom", :rel => "tooltip", :title => "Label color of event", :disabled => params[:action] == "show"
  %td
    = link_to_remove_association f, :class => "btn" do
      %i.icon-remove

请注意，.nested-fields标签上的类对于删除链接的工作是必不可少的。