Question

我跟随了Ryan Bate关于令牌输入的Railscast，它完全适用于我的发布＆＃39;等级使用：

 <%= f.text_field :artist_tokens, "data-pre" => @release.artists.map(&:attributes).to_json, :class => "text" %

根据发布，我有跟踪＆＃39;并希望能够在轨道级别修改和改变艺术家。使用上面我可以使它继承＆＃39;发布级别的艺术家和这似乎适用于新方法和初始设置，但在编辑它显然拉回发布级别的艺术家，如果提交它命中，那么所有的轨道级艺术家都被覆盖。

我试图这样做：

<% if params[:action] == "edit" %>
<%= f.text_field :artist_tokens, "data-pre" => @track.artists.map(&:attributes).to_json, :class => "text" %>
<% else %>
<%= f.text_field :artist_tokens, "data-pre" => @release.artists.map(&:attributes).to_json, :class => "track_artist_tokens" %>
<% end %>

但是我得到了一个未定义的方法＆＃39;艺术家＆＃39;在@ track.artists.map

我的模型如下：

class Release < ActiveRecord::Base
  has_many :artist_releases
  has_many :artists, :through => :artist_releases

  attr_reader :artist_tokens

    def artist_tokens=(ids)
      self.artist_ids = ids.split(",")
    end

  has_many :releases_tracks, :dependent => :destroy
  has_many :tracks, :through => :releases_tracks

  accepts_nested_attributes_for :tracks, :reject_if => lambda { |a| a[:name].blank? }, :allow_destroy => :true

  has_many :artists_tracks

end

class Artist < ActiveRecord::Base
  has_many :artist_releases
  has_many :releases, :through => :artist_releases  
  has_many :artists_tracks
  has_many :tracks, :through => :artists_tracks
end



   class Track < ActiveRecord::Base
      has_many :releases_tracks, :dependent => :destroy
      has_many :releases, :through => :releases_tracks

      has_many :artists_tracks
      has_many :artists, :through => :artists_tracks

      attr_reader :artist_tokens
      def artist_tokens=(ids)
        self.artist_ids = ids.split(",")
      end

    end

class ArtistsTrack < ActiveRecord::Base
  belongs_to :artist
  belongs_to :release
  belongs_to :track
end

class ReleasesTrack < ActiveRecord::Base
  belongs_to :release
  belongs_to :track
  acts_as_list
end

有人可以帮忙吗？

更新

发布控制器跟踪方法：

def tracks
     @release = Release.find(params[:id])
     @track = @release.tracks.find(:all)
        respond_to do |format|
        format.html # tracks.html.erb
        end
  end

tracks.html.erb有：

    <%= form_for @release do |f| %>
            <%= f.fields_for :tracks do |builder| %>
            <%= render 'track_fields', :f => builder %>
            <% end %>
<% end %>

_track_fields.html.erb partial（为清晰起见，部分HTML被剥离）

<td class="label">Title:</td>
<td class="field"><%= f.text_field :name, :class => "text" %></td>

<td class="label">Artists:</td>
<td class="field">
    <% @track.each do |track| %>
    <%= f.text_field :artist_tokens, "data-pre" => track.artists.map(&:attributes).to_json, :class => "track_artist_tokens" %>
    <% end %>

<p><%= link_to 'Add new artist', new_artist_path, :remote => true %></p>

<td class="label">Version:</td>
<td class="field"><%= f.text_field :version, :class => "text" %></td>

<td class="label">ISRC:</td>
<td class="field"><%= f.text_field :isrc, :class => "text" %></td>

<td class="label">Remove:</td>
<td class="field"><%= f.check_box :_destroy %></td>

Answer 1

在show操作中@track是一个track对象。在customer操作中，它是track个对象的集合。所以要么你必须遍历它们：

<% @track.each do |track| %>
  <%= f.text_field :artist_tokens, "data-pre" => track.artists.map(&:attributes).to_json, :class => "text" %>
<% end %>

或者获取该集合的第一个track：

<%= f.text_field :artist_tokens, "data-pre" => @track.first.artists.map(&:attributes).to_json, :class => "text" %>

Rails /令牌输入

1 个答案: