Question

I’m using periodically_call_remote to update a portion of a page that contains a list of objects. I send along with the url a param containing the created_at date for the most recent object in the database. The action that is called then get all the objects that have been created since then and renders a partial which displays them at the top of the list.

The problem is that I can’t seem to figure out how to make it so that the next time periodically_call_remote triggers it sends along the created_at date for the new most recent object (if there is one). I tried putting the periodically_call_remote inside the partial that is being rendered but that caused all sorts of problems (This explains why you shouldn’t do that).

Is there some way I can make periodically_call_remote send along a new param each time it’s called? As it stands right now it just sends the same one over and over which means that new objects get rendered more than once.

Answer 1

Hackery you say? 🙂

Store the parameter in a hidden div. You can access the contents of that div via Javascript, which periodically_call_remote will accept as part of the :with option.

When the parameter changes, simply update the contents of the hidden div as part of your controller action.

So, for example..

<div id="date_to_check_from" style="display:none;"><%= @initial_created_at %></div>

<%= periodically_call_remote :url => path_to_controller(@normal_params), :with => "'date_to_check_from=' + $('#date_to_check_from').html()", :method => :get, :frequency => 10 %>

That will get you params[:date_to_check_from] in your controller. Then update however you want, e.g.,

render :update do |page|
   page << "$('#date_to_check_from').html('#{@new_date_to_check_from}');
end