Rails 通过 jQuery Draggable Droppable 和 hidden_field_tag 更新 has_many答案

【问题标题】：Rails update has_many through jQuery Draggable Droppable and hidden_field_tagRails 通过 jQuery Draggable Droppable 和 hidden_field_tag 更新 has_many
【发布时间】：2011-07-04 00:03:18
【问题描述】：

我正在制作一个屏幕，人们通过将图片从画廊拖到托盘中来“投票”给彼此最喜欢的图片。我将 jQuery 用于可拖动/可放置。当用户将图像从图库拖到托盘时，我想更新我的 has_many :through 数据库中的关系（假期投票）。我正在尝试使用 hidden_field_tag 进行投票。

表单提交时我没有得到传递的参数。任何人都知道如何做到这一点？提前致谢！

模型

假期

class Vacation < ActiveRecord::Base
  belongs_to :user
  belongs_to :period
  has_many :votes
  has_many :images, :through => :votes
  accepts_nested_attributes_for :votes

  attr_accessible :user_id, :period_id, :name
end

投票

class Vote < ActiveRecord::Base
  belongs_to :vacation
  belongs_to :image

  attr_accessible :image_id, :vacation_id
end

图片

class Image < ActiveRecord::Base
  belongs_to :user
  belongs_to :category
  has_many :votes
  has_many :vacations, :through => :votes

  attr_accessible :user_id, :title, :facebook_id, :image

  validates_presence_of :user_id;
  validates_presence_of :title;
  validates_presence_of :image;

  validates_length_of :title, :maximum => 255

  mount_uploader :image, ImageUploader
end

Javascript

    var $gallery = $( "#gallery" ),
        $tray = $( "#tray_images" );

    $( "li", $gallery ).draggable({
      cancel: "a.ui-icon", 
      revert: "invalid", 
      cursor: "move",
      helper: "clone"
    });

    $tray.droppable({
      accept: "#gallery > li",
      drop: function( event, ui ) {
        moveImageToTray( ui.draggable );
        $( "#update_vacation" ).submit();
      }
    });

    function moveImageToTray( $item ) {
      $item.fadeOut(function() {
        $tray.append($item);
        $item.fadeIn();
      });
    }

视图 /vacations/show.html.erb

<%= form_for @vacation, :html => { :method => :put, :id => "update_vacation" } do |f| %>
  <%= hidden_field_tag :user_id, @vacation.user_id %>
  <%= hidden_field_tag :period_id, @vacation.period_id %>
  <%= hidden_field_tag :name, @vacation.name %>

  <div id="tray" class="grid_19 push_1 alpha">
    <ul id="tray_images" class="gallery">
      <% @votes.each do |vote| %>
        <li class="grid_3 image">
          <% link_to @images_all[i] do %>
            <% content_tag :div do %>
              <%= image_tag @images_all[i].image_url(:thumb_100_100) %>
              <%= hidden_field_tag "vacation[][image_ids]", vote.image_id %>
            <% end %>
          <% end %>
        </li>
      <% end %>
    </ul>
  </div>
<% end %>

<div class="clear"></div>  

<div class="grid_24">
<ul id="gallery" class="grid_19 push_1 alpha gallery">
  <% @images_all.each do |image| %>
      <li class="grid_3 image">
        <% link_to image do %>
          <% content_tag :div do %>
            <%= image_tag image.image_url(:thumb_100_100) %>
            <%= hidden_field_tag "vacation[image_ids][]", image.id %>
          <% end %>
        <% end %>
      </li>
    <% end %>
  <% end %>
</ul>

控制器

  def update
    params[:vacation][:votes] ||= []
    break

    @vacation = Vacation.find(params[:id])
    if @vacation.update_attributes(params[:vacation])
      redirect_to @vacation, :notice  => "Successfully updated vacation."
    else
      render :action => 'edit'
    end
  end

【问题讨论】：

标签： jquery ruby-on-rails draggable has-and-belongs-to-many

【解决方案1】：

如果您想在 params[:vacation] 哈希表中获取参数，请使用：

<%= f.hidden_field :field %>

而不是

<%= hidden_field_tag :field %>

您也可以考虑异步发送数据，而不是在每次拖放后提交表单。

【讨论】：