Rails checkbox change in db

I am total beginner in rails, trying to get some stuff together. I was browsing Stack Overflow about this issue for a while, but none of the advised stuff worked (and since I know Rails and Ruby are changing a lot - I guess it is normal).

So, the thing is - I want to create AJAX call when I click the checkbox, and later, change one boolean-type value in DB. My "object" is task and attribute is "status".

I tried:

<div class="header">  
<% form_for @task, :id => "status" do |f| %>  
<label><%= f.check_box :called, :onclick => "$('#status').submit()" %></label>  
<% end %>  
</div>

But it complains about undefined method model_name for NilClass:Class. Can you please maybe help with this?

Thank you very much.

EDIT:

Hmm, still that nasty error. Maybe the problem is in surroundings?

<% @tasks.each do |task| %>
<div class="post" id="<%= task.id =%>">
<div class="header"><%= form_for(@task, :id => "status", :remote => true) do |f| %>
<label>
<%= f.check_box :called %>
<%= f.su开发者_StackOverflow社区bmit %>
<% end %> <span class="title"><%= task.title =%></span>
</label>

The problem would seem to be that @task is nil. Perhaps copy and paste the controller code.

I would normally include a non-nil @task in both the "new" and "edit" actions

def new
  @task = Task.new
end

def create
  @task = Task.new(params[:task])
  ...
end

def edit
  @task = Task.find(params[:id])
end

I'm guessing in this example @task is nil.

Also I would suggest not using the :on_click html attribute. in particular, this will not send an ajax submit.

I suggest you use the jquery rails helpers to make it sent via ajax. Namely add the :remote => true param to form_for

<% form_for(@task, :id => "status", :remote => true) do |f| %>

Also in Rails >3 you should use the <%= for this type of tag.

<%= form_for(@task, :id => "status", :remote => true) do |f| %>

Lets rewrite it all

<%= form_for(@task, :id => "status", :remote => true) do |f| %>
  <%= f.check_box :called %>
  <%= f.submit %>
<% end %>
<script>
  jQuery(function($){
    // grab the form in this closure;
    var form = $("form#status");

    // hide the submit button
    form.find("input[type=submit]").hide();

    // set the click handler
    $("#task_called").click(function(){
      form.submit();
    });
  });
</script>

You should edit your question not post an answer with edits :)

Well, answer lies there:

1 <% @tasks.each do |task| %>
2 <div class="post" id="<%= task.id =%>">
3 <div class="header"><%= form_for(@task, :id => "status", :remote => true) do |f| %>
4 <label>
5 <%= f.check_box :called %>

Line 1 you loop @tasks and create task.

But line 3 you call @task instead of task