error rendering a flash message with jquery ajax in ruby on rails app_问答_开发者

error rendering a flash message with jquery ajax in ruby on rails app

开发者 https://www.devze.com 2023-02-15 14:30 出处：网络

Here\'s the error I get: ActionView::Template::Error (You have a nil object when you didn\'t expect it!

Here's the error I get:

ActionView::Template::Error (You have a nil object when you didn't expect it!
You might have expected an instance of Array.

It's referring to this code in a view partial:

<% flash.each do |key, value| %>
  <div class="<%= key %>"><%= value %></div>
<% end %>

I set the flash message in my micropost controller:

def create
@micropost  = current_user.microposts.build(params[:micropost])
respond_to do |format|
  if @micropost.save
    flash[:success] = "Micropost created!"
    format.html { redirect_to root_path, :notice => 'success' }
    format.js

Here's开发者_运维技巧 my js code in views/microposts/create.js.erb:

$('div.notice').append('<%= render 'shared/flash' %>');

And the partial gets rendered dynamically in my application layout:

<body>
  <div class="container">
    <%= render 'layouts/header' %>
    <section class="round">
  <div id= "notice"></div>
      <%= yield %>
    </section>
  <%= render 'layouts/footer' %>
  <%= debug(params) if Rails.env.development? %>
  </div>
</body>

How do I fix this error? What am I doing wrong?

The problem lies in the naming of your partial file.

Rails tries to be clever with partials and automagically exposes a local variable that shares the same name as the partial's file name. It does this because the most common use-case for partials to to bind an HTML fragment to an instance of something, ie:

# the following is treated as: render :partial => "frobs", :collection = @frobs
render @frobs

Then, within your _frob.html.erb partial, you have a variable named frob which references the current instance from @frobs

In your case, this is colliding with the flash method exposed by ActionView: a local variable will always trump a method name. Try re-naming your partial to something else (ie, flash_message), keeping the content the same and see if that works.