Question

我发现很多人遇到了同样的问题，但没有一个解决方案适用于我的情况。我关注Michael Hartl's tutorial here。我有一个按照第14章设置的跟随系统（我使用本书的最新版本，因为我在Rails 5.1上）。数据库中的follow / unfollow按钮进程，但我必须手动刷新页面才能看到按钮并按照计数更改。

我在浏览器控制台日志中得到了这个：

public boolean collidedBottom()
{ 
    if(c.getBall().getBallY() <= enemy.y + enemy.height && 
        c.getBall().getBallX() + c.getBall().getHitbox().width >= enemy.x
            && c.getBall().getBallX() <= enemy.x + enemy.width)
        return true;

    return false;
}

public boolean collidedTop()
{ 
    if(c.getBall().getBallY() + c.getBall().getHitbox().height >= enemy.y && 
         c.getBall().getBallX() + c.getBall().getHitbox().width >= enemy.x
            && c.getBall().getBallX() <= enemy.x + enemy.width)
        return true;

    return false;
}

relationships_controller.rb：

POST  500 (Internal Server Error)
    jquery.self-bd7ddd393353a8d2480a622e80342adf488fb6006d667e8b42e4c0073393abee.js:10255 
    send @ jquery.self-bd7ddd393353a8d2480a622e80342adf488fb6006d667e8b42e4c0073393abee.js:10255
    ajax @ jquery.self-bd7ddd393353a8d2480a622e80342adf488fb6006d667e8b42e4c0073393abee.js:9739
    ajax @ jquery_ujs.self-784a997f6726036b1993eb2217c9cb558e1cbb801c6da88105588c56f13b466a.js:94
    handleRemote @ jquery_ujs.self-784a997f6726036b1993eb2217c9cb558e1cbb801c6da88105588c56f13b466a.js:179
    (anonymous) @ jquery_ujs.self-784a997f6726036b1993eb2217c9cb558e1cbb801c6da88105588c56f13b466a.js:512
    dispatch @ jquery.self-bd7ddd393353a8d2480a622e80342adf488fb6006d667e8b42e4c0073393abee.js:5227
    elemData.handle @ jquery.self-bd7ddd393353a8d2480a622e80342adf488fb6006d667e8b42e4c0073393abee.js:4879

视图/用户/ _follow.html.erb：

class RelationshipsController < ApplicationController
  before_action :authenticate_user!

  def create
    user = User.find(params[:followed_id])
    current_user.follow(user)
    respond_to do |format|
      format.html { redirect_to(:back) }
      format.js 
    end
  end

  def destroy
    user = Relationship.find(params[:id]).followed
    current_user.unfollow(user)
    respond_to do |format|
      format.html { redirect_to(:back) }
      format.js 
    end
  end
end

视图/用户/ _unfollow.html.erb

<%= form_for(current_user.active_relationships.build, remote: true) do |f| %>
  <div><%= hidden_field_tag :followed_id, @user.id %></div>
  <%= f.submit "Follow", class: "btn btn-primary" %>
<% end %>

视图/用户/ _follow_form.html.erb

<%= form_for(current_user.active_relationships.find_by(followed_id: @user.id),
                   html: { method: :delete }, remote: true) do |f| %>
  <%= f.submit "Unfollow", class: "btn" %>
<% end %>

关系/ create.js.erb

<% if current_user != @user %>
  <div id="follow_form">
    <% if current_user.following?(@user) %>
      <%= render 'unfollow' %>
    <% else %>
      <%= render 'follow' %>
    <% end %>
  </div>
<% end %>

关系/ destroy.js.erb

$("#follow_form").html("<%= escape_javascript(render('users/unfollow')) %>");
$("#followers").html('<%= @user.followers.count %>');

users_controller.rb

$("#follow_form").html("<%= escape_javascript(render('users/follow')) %>");
$("#followers").html('<%= @user.followers.count %>');

我做错了什么？

Answer 1

您设置了本地变量user

def create
  user = User.find(params[:followed_id])

但是@user模板中的引用类实例变量.js.erb。

$("#followers").html('<%= @user.followers.count %>');

相反，请设置@user = User.find(params[:followed_id])以使其可供视图使用。实际上，我认为你正试图设置@user = current_user。这可能更有意义。

Answer 2

您需要重命名Javascript文件才能使.erb结束。

relationships/create.js.erb和relationships/destroy.js.erb。这是因为你在文件中有Ruby，因此在它被解释为Javascript并发回之前它必须处理Ruby。

http://guides.rubyonrails.org/working_with_javascript_in_rails.html#a-simple-example

AJAX按钮处理，不会改变

2 个答案: