我创建了一个ProjectRelationship模型来保存两个组件：用户的follower_id和项目的projectuser_id.外键已经设置好了.

现在,我的_follow_form.html.erb页面呈现“follow”或“unfollow”,具体取决于current_user是否跟随项目.我在下面附上了我的代码.

现在,在每个项目显示页面上生成跟随按钮.单击_follow.html.erb生成的按钮后,它会相应地跟随项目.

但当我按“取消关注”时,我收到一个错误：

NoMethodError in ProjectRelationshipsController#destroy
undefined method `unfollow_project!' for #<User:0x007f9ed83dd6b8>

Application Trace | Framework Trace | Full Trace
app/controllers/project_relationships_controller.rb:12:in `destroy'

schema.rb

create_table "project_relationships",:force => true do |t|
  t.integer  "follower_id"
  t.datetime "created_at",:null => false
  t.datetime "updated_at",:null => false
  t.integer  "projectuser_id"
end

add_index "project_relationships",["projectuser_id"],:name => "index_project_relationships_on_projectuser_id"

的routes.rb

resources :projects do       
  resources :comments 
  member do
    get :following
  end   
end
resources :project_relationships,only: [:create,:destroy]

project_relationship.rb

class ProjectRelationship < ActiveRecord::Base
   attr_accessible :projectuser_id

   belongs_to :user,foreign_key: "follower_id"
   belongs_to :project,foreign_key: "projectuser_id"
end

project.rb

has_many :project_relationships,foreign_key: "projectuser_id"
has_many :favorited_by,through: :project_relationships,source: :user

user.rb

has_many :project_relationships,foreign_key: "follower_id"
has_many :followed_projects,source: :project

def following_project?(project)
  project_relationships.find_by_projectuser_id(project.id)
end

def follow_project!(project)
  project_relationships.create!(projectuser_id: project.id)
end

def project_unfollow!(project)
  project_relationships.find_by_projectuser_id(project.id).destroy
end

project_relationships_controller.rb

class ProjectRelationshipsController < ApplicationController

def create
    @project = Project.find(params[:project_relationship][:projectuser_id])
    current_user.follow_project!(@project)
    redirect_to @project
  end

  def destroy
    @project = ProjectRelationship.find(params[:id]).project
    current_user.unfollow_project!(@project)
    redirect_to @project
  end
end

项目/ show.html.erb

<%= render 'follow_form' if signed_in? %>

项目/ _follow_form.html.erb

<% if current_user.following_project?(@project) %>
    <%= render 'unfollow' %>
<% else %>
    <%= render 'follow' %>
<% end %>

项目/ _follow.html.erb

<%= form_for(current_user.project_relationships.build(projectuser_id: @project.id)) do |f| %>
  <div><%= f.hidden_field :projectuser_id %></div>
  <%= f.submit "Follow",class: "btn btn-large btn-primary" %>
<% end %>

项目/ _unfollow.html.erb

<%= form_for(current_user.project_relationships.find_by_projectuser_id(@project),html: { method: :delete }) do |f| %>
  <%= f.submit "Unfollow",class: "btn btn-large" %>
<% end %>

项目/ _followerstats.html.erb

<%= @project.favorited_by.count %>