Question

I’m wanting to add some AJAX functionality to my Rails app, but have no idea where to start.

Here is the method that adds an item to an order:

def add_item_to_order
 if session[:order_id].nil?
   @order = Order.new #Don't create an order until there is an item to be added to it.
   @order.account_id = session[:user_id]
 else
   @order = Order.find(session[:order_id])
 end
 item = Item.find(params[:id])
 o_item = OrderItem.new
 o_item.item_id = item.id
 @order.order_items << o_item
 @order.total += item.sale_price
 @order.save
 session[:order_id] = @order.id
 redirect_to order_home_path
end

This is run when the user clicks:

<%= link_to item.name, add_item_to_order_path(item.id), :class => "fixed medium green button"%>

Can anyone give me any tips on how to get started, so the the item is added to the order via AJAX?

Answer 1

Great tutorial, did this myself: http://ruby.railstutorial.org/ruby-on-rails-tutorial-book Chapter 12 has some stuff on Ajax.

Important part is to set your link_to paramater data-remote to true:

<%= link_to item.name, add_item_to_order_path(item.id), 
    :class => "fixed medium green button" data-remote="true" method="post"%>

and in your controller you add

def add_item_to_order
    # other stuff
    # at the bottom:
    respond_to do |format|
          format.html { redirect_to order_home_path }
          format.js
        end

end

Then you’ll need a .js.erb file to handle the format.js repsonse:

$("your_form").update("<%= escape_javascript(render('partial_page')) %>")

and a partial page file to hold the new data..