Agile Web Development with Rails, Edition 4

11.3 Iteration F3: Highlighting Changes

Assign the current item to be the line item in question

edit app/controllers/line_items_controller.rb

  def create

    product = Product.find(params[:product_id])

    @line_item = @cart.add_product(product.id)

    @line_item.product = product

    respond_to do |format|

      if @line_item.save

        format.html { redirect_to(store_url) }

        format.js   { @current_item = @line_item }

        format.xml  { render :xml => @line_item,

          :status => :created, :location => @line_item }

      else

        format.html { render :action => "new" }

        format.xml  { render :xml => @line_item.errors,

          :status => :unprocessable_entity }

end

end

end

Add the id to the row in question

edit app/views/line_items/_line_item.html.erb

<% if line_item == @current_item %>

<tr id="current_item">

<% else %>

<tr>

<% end %>

  <td><%= line_item.quantity %>&times;</td>

  <td><%= line_item.product.title %></td>

  <td class="item_price"><%= number_to_currency(line_item.total_price) %></td>

</tr>

Animate the background color of that row

edit app/views/line_items/create.js.rjs

page.replace_html('cart', render(@cart))

page[:current_item].visual_effect :highlight,

                                  :startcolor => "#88ff88",

                                  :endcolor => "#114411"