Question

我遇到了下面显示的代码问题！我想创建一个显示用户名列表的视图（如user_weight方法中的@participate所示）。在我希望提供下拉列表的名称旁边，您可以在其中为特定用户分配1到5之间的值。

现在我完全卡住了！该视图仅显示我对问题的处理方法根本不起作用...（：与会者＆amp;：user_weight现在只是占位符）

如果我尝试它的方式我得到一个：＆＃34;未定义的方法`merge＆＃39; [[＆＃34; 1＆＃34;，1]，[＆＃34; 2＆＃34;，2]，[＆＃34; 3＆＃34;，3]，[＆＃34; 4＆＃34; ，4]，[＆＃34; 5＆＃34;，5]]：数组＆＃34;错误

希望有人有个主意！

文件：

user_weight.html.erb

<%= form_for @users, :url => {action: "create_user_weight"} do |f| %>

<ul>
  <% @users.each do |user| %>
      <li> <%= user.username %> <%= f.select(:attendee, :user_weight, [['1', 1], ['2', 2], ['3', 3], ['4', 4], ['5', 5]]) %> </li>
  <% end %>
  <p>
    <%= button_to "Select User Weight", action: "create" %>
  </p>
<% end %>
</ul>

schema.rb

  create_table "attendees", force: true do |t|
    t.integer  "task_id"
    t.integer  "user_id"
    t.boolean  "participate"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.integer  "user_weight"
  end

  create_table "friendships", force: true do |t|
    t.integer  "user_id"
    t.integer  "friend_id"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

  create_table "selectdates", force: true do |t|
    t.datetime "task_date"
    t.boolean  "participate"
    t.integer  "attendee_id"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.integer  "task_id"
  end

  create_table "tasks", force: true do |t|
    t.string   "title"
    t.text     "text"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.boolean  "participate"
    t.date     "meeting_date"
    t.time     "meeting_start_time"
    t.time     "meeting_end_time"
  end

  create_table "users", force: true do |t|
    t.string   "email"
    t.string   "password_hash"
    t.string   "password_salt"
    t.string   "username"
    t.string   "company"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

end

tasks_controller.rb

  def select_user
    @user = User.all
    @task = Task.find(params[:id])
  end

  def participate
    @task = Task.find(params[:id])
    @task.users << User.all

    @attendees = Attendee.where(User_id: params[:user_checkbox])
    Attendee.transaction do
      @attendees.each do |attendee|
        attendee.update_attributes!(participate: true)
      end
    end

    redirect_to :action => 'user_weight', :id => @task
  end


  def user_weight
    @participants = Attendee.where(participate: true, task_id: params[:id])
    @users = @participants.map { |p| User.find_by id: p.user_id }.to_set.to_a
  end

attendee.rb

class Attendee < ActiveRecord::Base
  belongs_to :task
  belongs_to :user
end

user.rb

class User < ActiveRecord::Base
  has_many :attendees
  has_many :tasks, :through => :attendees

  has_many :friendships
  has_many :friends, :through => :friendships

  has_many :selectdates
end

task.rb

class Task < ActiveRecord::Base
  has_many :attendees
  has_many :users, :through => :attendees
  has_many :selectdates, dependent: :destroy
end

的routes.rb

Rails.application.routes.draw do

  #match ':controller(/:action(/:id))(.:format)', via: [:get, :post]

  get 'tasks/new'
  get 'tasks/create'
  get 'tasks/select_date'
  get 'tasks/user_weight', :as => "user_weight"
  get 'tasks/select_user', :as => "select_user"

  match "tasks/participate" => "tasks#participate", :via => :post
  match "tasks/create_date" => "tasks#create_date", :via => :patch, :as => "create_date"
  match "tasks/create_user_weight" => "tasks#create_user_weight", :via => :patch, :as => "create_user_weight"


  resources :tasks

  get "logout" => "sessions#destroy", :as => "logout"
  get "login" => "sessions#new", :as => "login"
  get "signup" => "users#new", :as => "signup"
  get "account" => "sessions#account", :as => "account"

  get "addfriends" => "friendships#new", :as => "addfriends"

  resources :users do
    collection do
      update 'multiple_update'
    end
  end



  resources :sessions
  resources :friendships



  root 'welcome#index'

Answer 1

form_for不知道如何正确处理一组用户。我会为此使用form_tag。您需要在用户控制器中执行自定义操作。我建议像这样设置：

#routes
resources :users do
  collection do
    update 'multiple_update'
  end
end

#controller
#expects params like {:users => {123 => {:weight => 3}, 456 => {:weight => 4}} 
#where 123 and 456 are user ids
def multiple_update
  @users = []
  params[:users].each do |id, attributes|
    if user = User.find_by_id(id)
      if user.update_attributes(attributes)
        @users << user
      end
    end
  end
end

#view 
<% form_tag multiple_update_users_path, :method => :update do %>
  <ul>
    <% @users.each do |user| %>
      <li> <%= user.username %> <%= select_tag "users[#{user.id}][weight]", options_for_select([['1', 1], ['2', 2], ['3', 3], ['4', 4], ['5', 5]], user.weight) %> </li>
    <% end %>
  </ul>
  <%= submit_tag "Update" %>
<% end %>

通过rails 4中的html表单一次向多个对象添加值

1 个答案: