渲染:以自定义形式从ID到ID的部分随机对象

时间:2012-09-13 16:47:45

标签: ruby-on-rails-3 partial-views

我正在尝试从数据库中呈现随机对象。 步骤:1。generate button(主页) - > 2.致电rand_task(控制人员) - > 3. _rand_show.html.erb(表格)

问题:它现在崩溃,但有一次它起作用。(我知道在编码中没有这样的东西,但我无法设法看到问题...) 主:

<%= form_for(:task, :url => {:action =>'rand_task', :id => 'random'}) do |f|%>
<%= render(:partial => "rand_show", :locals => {:f => f}) %></p> 
<%end%>

控制器:

def rand_task
  @task = Task.order('RANDOM()').first
end

形式:

<%= form_for(@task) do |f| %>
  <div class="field">
    <%= f.label :name %><br />
    <%= f.text_field :name, :disabled=>true %>

  <div class="field">
    <%= f.label :category %><br />
    <%= f.text_field :category, :disabled=>true %>
  </div>
  <div class="actions">
    <%= f.submit "generate"%>
  </div>
<% end %>

服务器:

Started GET "/" for 127.0.0.1 at 2012-09-13 19:35:56 +0300
Processing by TasksController#main as HTML
  Rendered tasks/_rand_show.html.erb (0.8ms)
  Rendered tasks/main.html.erb within layouts/application (1.6ms)
Completed 500 Internal Server Error in 4ms

ActionView::Template::Error (undefined method `model_name' for NilClass:Class):
    1: <%= form_for(@task) do |f| %>
    2:   <div class="field">
    3:     <%= f.label :name %><br />
    4:     <%= f.text_field :name, :disabled=>true %>
  app/views/tasks/_rand_show.html.erb:1:in `_app_views_tasks__rand_show_html_erb__183960888__627313568'
  app/views/tasks/main.html.erb:2:in `block in _app_views_tasks_main_html_erb__298912262__627495408'
  app/views/tasks/main.html.erb:1:in `_app_views_tasks_main_html_erb__298912262__627495408'

如果我添加<%= form_for(@task _=Task.new_ ) do |f| %>而不是删除它,它只能用于一次实例

2 个答案:

答案 0 :(得分:1)

此错误告诉您在这种情况下@task对象为nil。你需要确保你的&#34;任务&#34;中有记录。表

答案 1 :(得分:0)

修正:要访问本地变量,您需要在我的案例resources :tasks中将表添加到config / routes.rb

编辑:服务器重启后问题仍然存在。