Ruby on rails 后续和后续事件

我已经完成了MichaelHartlRubyonRails 5教程，现在正试图将代码应用到我自己的应用程序中

我想做的是：

• 跟踪/取消跟踪事件
• 显示此事件后的用户总数
• 用户可以看到他们正在关注的所有事件

当前错误出现在我尝试呈现当前用户正在跟踪的会议时

我得到的错误是：

ActionController::UrlGenerationError in Users#show
No route matches {:action=>"followers", :controller=>"conferences", :id=>nil} missing required keys: [:id]

导致问题的线路是：

  <a href="<%= followers_conference_path(@conference) %>">

ROUTES.RB

Rails.application.routes.draw do

  root   'static_pages#home'

  get    '/help',    to: 'static_pages#help'
  get    '/about',   to: 'static_pages#about'
  get    '/contact', to: 'static_pages#contact'

  get    '/my_conference', to: 'my_conference#show'
  get    '/conferences', to: 'conferences#index'
  get    '/conferences_list', to: 'conferences#index_admin'

  get    '/my_employees', to: 'employees#index'

  get    '/signup',  to: 'users#new'

  get    '/login',   to: 'sessions#new'
  post   '/login',   to: 'sessions#create'
  delete '/logout',  to: 'sessions#destroy'

  get    '/login',   to: 'sessions#new'

  put 'activate/:id(.:format)', :to => 'users#activate', :as => :activate_user
  put 'deactivate/:id(.:format)', :to => 'users#deactivate', :as => :deactivate_user

  put 'activate_employee/:id(.:format)', :to => 'employees#activate', :as => :activate_employee
  put 'deactivate_employee/:id(.:format)', :to => 'employees#deactivate', :as => :deactivate_employee

  resources :users do
    member do
      get :following
    end
  end
  resources :conferences do
    member do
      get :followers
    end
  end
  resources :articles
  resources :users
  resources :employees
  resources :account_activations, only: [:edit]
  resources :activations, only: [:edit]
  resources :password_resets,     only: [:new, :create, :edit, :update]
  resources :microposts,          only: [:create, :destroy]
  resources :managments  
  resources :conferences  
  resources :relationships,       only: [:create, :destroy]


end

class ConferencesController < ApplicationController
  before_action :logged_in_user, only: [:create, :destroy]
  before_action :correct_user,   only: :destroy
  before_action :admin_user,     only: :destroy

    def index

      @conferences = Conference.paginate(page: params[:page])

      if params[:search]
        @conferences = Conference.search(params[:search]).order("created_at DESC").paginate(page: params[:page])
      else
        @conferences = Conference.all.order('created_at DESC').paginate(page: params[:page])
      end
    end

  def new
    @user = User.new
    @conference = Conference.new
  end

  def create

    @conference = current_user.conferences.build(conference_params)
    if @conference.save
      flash[:success] = "conference created!"
      redirect_to conferences_path
    else
      @feed_items = current_user.feed.paginate(page: params[:page])
      render 'new'
    end
  end

  def destroy
    @conference.destroy
    flash[:success] = "conference deleted"
    redirect_to request.referrer || root_url
  end

  def following
    @title = "Following"
    @conference  = Conference.find(params[:id])
    @conferences = @conference.following.paginate(page: params[:page])
    render 'show_follow'
  end

  def followers
    @title = "Followers"
    @user  = User.find(params[:id])
    @users = @user.followers.paginate(page: params[:page])
    render 'show_follow'
  end


  private

    def conference_params
      params.require(:conference).permit(:conference,:country , :month, :presence, :audience, :cost ,:picture)
    end

    # Confirms an admin user.
    def admin_user
      redirect_to(root_url) unless current_user.admin?
    end

    def correct_user
      @conference = current_user.conferences.find_by(id: params[:id])
      redirect_to root_url if @conference.nil?
    end

end

CONFERENCES\u CONTROLLER.RB

Rails.application.routes.draw do

  root   'static_pages#home'

  get    '/help',    to: 'static_pages#help'
  get    '/about',   to: 'static_pages#about'
  get    '/contact', to: 'static_pages#contact'

  get    '/my_conference', to: 'my_conference#show'
  get    '/conferences', to: 'conferences#index'
  get    '/conferences_list', to: 'conferences#index_admin'

  get    '/my_employees', to: 'employees#index'

  get    '/signup',  to: 'users#new'

  get    '/login',   to: 'sessions#new'
  post   '/login',   to: 'sessions#create'
  delete '/logout',  to: 'sessions#destroy'

  get    '/login',   to: 'sessions#new'

  put 'activate/:id(.:format)', :to => 'users#activate', :as => :activate_user
  put 'deactivate/:id(.:format)', :to => 'users#deactivate', :as => :deactivate_user

  put 'activate_employee/:id(.:format)', :to => 'employees#activate', :as => :activate_employee
  put 'deactivate_employee/:id(.:format)', :to => 'employees#deactivate', :as => :deactivate_employee

  resources :users do
    member do
      get :following
    end
  end
  resources :conferences do
    member do
      get :followers
    end
  end
  resources :articles
  resources :users
  resources :employees
  resources :account_activations, only: [:edit]
  resources :activations, only: [:edit]
  resources :password_resets,     only: [:new, :create, :edit, :update]
  resources :microposts,          only: [:create, :destroy]
  resources :managments  
  resources :conferences  
  resources :relationships,       only: [:create, :destroy]


end

class ConferencesController < ApplicationController
  before_action :logged_in_user, only: [:create, :destroy]
  before_action :correct_user,   only: :destroy
  before_action :admin_user,     only: :destroy

    def index

      @conferences = Conference.paginate(page: params[:page])

      if params[:search]
        @conferences = Conference.search(params[:search]).order("created_at DESC").paginate(page: params[:page])
      else
        @conferences = Conference.all.order('created_at DESC').paginate(page: params[:page])
      end
    end

  def new
    @user = User.new
    @conference = Conference.new
  end

  def create

    @conference = current_user.conferences.build(conference_params)
    if @conference.save
      flash[:success] = "conference created!"
      redirect_to conferences_path
    else
      @feed_items = current_user.feed.paginate(page: params[:page])
      render 'new'
    end
  end

  def destroy
    @conference.destroy
    flash[:success] = "conference deleted"
    redirect_to request.referrer || root_url
  end

  def following
    @title = "Following"
    @conference  = Conference.find(params[:id])
    @conferences = @conference.following.paginate(page: params[:page])
    render 'show_follow'
  end

  def followers
    @title = "Followers"
    @user  = User.find(params[:id])
    @users = @user.followers.paginate(page: params[:page])
    render 'show_follow'
  end


  private

    def conference_params
      params.require(:conference).permit(:conference,:country , :month, :presence, :audience, :cost ,:picture)
    end

    # Confirms an admin user.
    def admin_user
      redirect_to(root_url) unless current_user.admin?
    end

    def correct_user
      @conference = current_user.conferences.find_by(id: params[:id])
      redirect_to root_url if @conference.nil?
    end

end

class ConferencesController

啊，我明白了

检查您的

用户控制器#show

，查看是否在任何地方设置了

@conference

如果不尝试：

啊，我看到问题了

检查您的

用户控制器#show

，查看是否在任何地方设置了

@conference

---

如果不尝试：

我敢肯定，您不想使用用户id获取@conference对象。相反，您可能正在生成用户正在关注的会议列表。在这种情况下，你会使用这样的东西

<% @user.conferences.each do |conference| %>
  <a href="<%= followers_conference_path(conference) %>"><%= conference.name %></a>
<% end %>

---

我敢肯定，您不想使用用户id获取@conference对象。相反，您可能正在生成用户正在关注的会议列表。在这种情况下，你会使用这样的东西

<% @user.conferences.each do |conference| %>
  <a href="<%= followers_conference_path(conference) %>"><%= conference.name %></a>
<% end %>

---

您能发布导致错误的行吗？不是路由，

\u path

方法可能需要IDpassed@Ruslan我真蠢，不加上它。我加了一句，我明白了。检查您的

用户控制器#show

，查看是否在任何地方设置了

@conference

。如果没有，请尝试：

@Ruslan感谢您的回复。它没有显示在UsersController#show中。你能告诉我（甚至解释一下）我应该如何在UsersController#show中编写它吗？谢谢大家!@臭名昭著的信条您在哪里添加了这一行，即在哪个视图中？我感觉的问题是，如果它位于像new这样的路径上，会议刚刚初始化但没有保存，所以它没有Id。或者它甚至还不存在。你能发布导致错误的行吗？不是路由，

\u path

方法可能需要IDpassed@Ruslan我真蠢，不加上它。我加了一句，我明白了。检查您的

用户控制器#show

，查看是否在任何地方设置了

@conference

。如果没有，请尝试：

@Ruslan感谢您的回复。它没有显示在UsersController#show中。你能告诉我（甚至解释一下）我应该如何在UsersController#show中编写它吗？谢谢大家!@臭名昭著的信条您在哪里添加了这一行，即在哪个视图中？我感到的问题是，如果它位于像new这样的路径上，会议刚刚初始化，但没有保存，因此它没有Id。或者它甚至还不存在。我已将

@conference=conference.find（params[：Id]）

添加到

userscocontroller#show

中，现在它正在工作。非常感谢你！！！我已经将

@conference=conference.find（params[：id]）

添加到

userscocontroller\show

中，现在它开始工作了。非常感谢你！！！谢谢你的回复，我今天会尝试一下，然后再回复你！谢谢你的回复，我今天会尝试一下，然后再回复你！