Question

我正在尝试创建一个表单，用户可以在其中查看他们的朋友列表，并在列表中添加或删除朋友（有点像facebook的小组）。对于创建列表视图，我可以使表单正常工作，但对于编辑视图，我遇到了check_box语法和fields_for的问题。

routes.rb
  resources :friendships
  resources :friend_lists

class User < ActiveRecord::Base
has_many :friendships, dependent: :destroy
  has_many :friends, through: :friendships
  has_many :friend_lists
  has_many :flist_memberships, class_name: 'FlistMembership', foreign_key: 'member_id', dependent: :destroy
...
end

class FriendList < ActiveRecord::Base
  belongs_to :user
  has_many :flist_memberships
  has_many :members, through: :flist_memberships

  accepts_nested_attributes_for :members, allow_destroy: true
  accepts_nested_attributes_for :flist_memberships, allow_destroy: true
end

class FlistMembership < ActiveRecord::Base
  belongs_to :friend_list
  belongs_to :member, class_name: 'User'
end

class FriendListsController < ApplicationController
  def new
    @friend_list = current_user.friend_lists.build
    @friends = current_user.friends.paginate(page: params[:page])
    @friend_list.flist_memberships.build
  end

  def create
    @friend_list = current_user.friend_lists.build(friend_list_params)
    respond_to do |format|
        format.html {
          if @friend_list.save
            flash[:success] = "Friends list created!"
            redirect_to friendships_path
          else
            render 'friend_lists/new'
          end
          }
      end
  end

  def edit
    @friend_list = FriendList.find(params[:id])
    @friends = current_user.friends
  end

  def update
    @friend_list = FriendList.find(params[:id])
    if @friend_list.update_attributes(friend_list_params)
      flash[:success] = "Friend list updated!"
      redirect_to friend_list_path(@friend_list)
    else
      render 'edit'
    end
  end

  private

  def friend_list_params
    params.require(:friend_list).permit(:name, flist_memberships_attributes: [:id, :member_id, :friend_list_id])
  end
end

new.html.erb

<%= form_for @friend_list do |f| %>
  <%= f.label :name, "Name for this friends list:" %>
  <%= f.text_field :name %>
  <% @friends.each do |friend| %>
    <%= f.fields_for :flist_memberships do |m| %>
      <%= m.check_box :member_id, {}, friend.id %>
      <%= m.label :member_id, friend.name %>
    <% end %>
  <% end %>
  <%= f.submit "Save", class: "btn btn-primary" %>
<% end %>

edit.html.erb

<%= form_for @friend_list do |f| %>
  <%= f.label :name, "Name for this friends list:" %>
  <%= f.text_field :name %>
  <%= f.fields_for :flist_memberships do |m| %>
    <%= m.collection_check_boxes(:member_id, @friends.all, :id, :name) %>
  <% end %>
  <%= f.submit "Save", class: "btn btn-primary" %>
<% end %>

new.html.erb正确呈现并保存所选项目，但我无法弄清楚如何编写编辑表单，以便它不会为集合中的每个项目迭代一次集合（包含collection_check_boxes和new.html.erb中编写的表单）。试图

<%= f.fields_for :flist_memberships do |m| %>
  <%= m.check_box :id %>
  <%= m.label :id, :name %>
<% end %>

编辑表单中的

只传递字符串＆＃34; id＆＃34;作为参数而不是拉动集合中每个成员的id，我不知道如何在不迭代集合的情况下拉出单个项目的名称/ id，这又回到了多重渲染问题。我在项目的其他地方使用了茧，但为此，我宁愿向用户提供所有选项的列表，并允许他们为每个选项选中一个方框，而不是必须手动添加每个项目。名单。如果有办法用茧做，我很高兴听到它。

Rails嵌套表单fields_for在编辑时加倍

0 个答案: