Rails 3 - link_to to call partial using jquery ajax

Question

I am trying to get a link_to to display a partial via jquery ajax, but can't seem to get it to work (edit: returning blank screen) and I'm not sure what I'm missing. Any help would be appreciated.

I would like to click the link "Preview Widget" and have it display _widget.html.erb in the div preview.

From my understanding the link "Preview Widget" should call the action def preview_widget which calls preview_widget.js.erb which then renders the partial _widget.html.erb in the div.

EDIT: updates link as per Ignatius Reza suggestions

show.html.erb

<%= link_to "Preview Widget", :action => 'preview_widget' , :id => @widget.id, :remote => true %> %>
<div id="preview"></div>

widget_controller.rb

def preview_widget  
    respond_to do | format |  
        format.js {render :layout => false}  
    end
end

preview_widget.js.erb

$( "#preview" ).html( "<%= escape_javascript( render( :partial => "widget", :locals => { :widget => @widget} ) ) %>" );

_widget.html.erb

<% @widget.videos.each do |video| %>
      <h3><a href='#'><%= video.name %></a></h3>
      <div>
        <object height='316' width='540'>
          <embed  style='border: 1px solid #333333;' height='316' width='540' allowfullscreen='true' allowscriptaccess='always' type='application/x-shockwave-flash' src='<%= video.url %>'>
        </object>
      </div>
  <% end %>

routes.rb

match 'preview_widget' => 'widgets#preview_widget'

Answer 1

Ok finally got this to work with the following changes.
routes.rb (added member to widget resources)

  resources :widgets do
    member do
      get 'preview_widget'
    end
  end

show.html.erb (changed link_to to match routes)

<%= link_to 'Preview', preview_widget_widget_path(:id => @widget.id),  :remote => true %>

This now shows the partial. I am still not 100% sure what was wrong with the previous code - at least it now works.

Answer 2

It's not cleared on your question, what you "can't seem to get it to work".. but from what i see in the code you gave.. all seems right, but you miss the actual ajax call..

it could be added by adding :remote => true to the "Preview Widget" link such as :

<%= link_to "Preview Widget", :action => 'preview_widget' , :id => @widget, :remote => true %>

if the default behaviour is enough.. or you could add your own custom ajax call on application.js..

as a note, i don't think setting the :id attribute of "Preview Widget" link to @widget is wise.. as it will put the string representation of widget, which usually will looks like "<Widget:0x12412 ..>" perhaps it would be better to change it to "widget-link-#{@widget.id}"

Answer 3

I’ve a similar problem that brought me to this threat, so I thought sharing my solution here might be helpful to anybody.

With :remote => true I got an normal HTTP Request to http://localhost:3000/info/about?remote=true instead of the wanted AJAX Request to http://localhost:3000/info/about

The fix was easy but hard to find!

In my HAML View:

WRONG Code that triggers HTTP Request

= link_to( image_tag("icons/information.png", :title => t('menu.info')), :controller => "info", :action => "about", :remote => true )

OK-Code that triggers AJAX Request

= link_to( image_tag("icons/information.png", :title => t('menu.info')), {:controller => "info", :action => "about"}, :remote => true )

The only difference is {curly brackets}!

Funny though is that with the AJAX Request I get info/about.html rendered, without the layout file. Which isn’t a partial but is close to what Jan wanted. I was expecting info/about.js.erb to be rendered.

In InfoController

  def about
    respond_to do |format|
      format.html # renders ‘views/info/about.html.erb’ inside layout template on HTTP Request
      format.js# renders ‘views/info/about.html.erb’, without layout
    end
  end

-

  def about
    respond_to do |format|
      format.html # => ‘views/info/about.html.erb’ inside layout template on HTTP Request
      format.js {render 'about.js'} # => renders ‘views/info/about.js.erb’
    end
  end