Question

Update: My question was answered, but I wrote a blog post detailing exactly how I went about doing this: http://lathamcity.com/posts/ajaxInRails.html

I have a page that shows a list of things based on a Ruby object. My goal is to make an Ajax call to get a new Ruby object and then update the list based on that.

I thought that the way to do this was with partials. I make the entire list a partial file with the Rails instance variable in the code. Then I want the Ajax call to set the corresponding instance variable to the new list and re-render the partial.

That’s the end goal, but right now I’m trying to do a really basic version of that where I just set an instance variable to a string and then show the string.

So in my div, I have:

<% form_tag :action => :go , :method => :get, :remote => true  do %>
    <%= submit_tag "Go" %>
<% end %>

<div id="test"><%= render(:partial => 'test') %></div>

There’s a _test.erb file in the views/interface (the name of my controller) folder, with only the following line as its contents:

<%= @test %>

And then in my controller,

def go
    @test = "Hello You"
    render :update do |page|
        page.replace_html "test", :partial => "test"
    end
end

When I run this, I get: Missing template interface/update, application/update

I don’t know much about render :update, I found it in an example on Google.

What am I doing wrong that is causing this problem and how can I fix it? Am I going about this the right way or is there a better way to do it?

Answer 1

I think both render :update and replace_html were deprecated/removed in rails 3.1. The standard way of doing partial updates is to use a js.erb template.

In your controller, tell your action to respond to js request:

@test = "Hello you"
respond_to do |format|
    format.js
end

Create the js response template app/views/interface/go.js.erb:

$('#test').html("<%= escape_javascript(render('test', test: @test})) %>")

and change the partial code to <%= test %> because this is no longer an instance variable; rather, test is being passed to the partial as an argument from the js.erb template with test: @test