How do I add a '+1' link in a Rails 3 app that when clicked increases the Upvotes value by 1?

I'm new to programming.

I generated an Ideas scaffold. The model has fields: Description (string), Upvotes (integer), Downvotes (integer).

All the normal actions in the ideas_controller.rb work - Index, Show, New, Edit, Create, Update, Destroy.

Instead of telling you the ways I've tried to do the following, I'll just ask:

How do I add a '+1' link next to the 'Show', 'Edit', 'Destroy' links that when clicked increases the Upvotes value by 1 for that idea?

Thanks in advance.

EDIT (With "Skydreamer's" help, I figured it out!)

I adjust the routes.rb to:

   resources :ideas do
     member do
       get 'upvote'
     end
   end

I add the following to the ideas index.html.erb:

<td><%= link_to '+1', upvote_idea_path(idea) %&g开发者_如何学Got;</td>

Note: if you don't include the (idea), you'll get an error like this:

No route matches {:action=>"upvote", :controller=>"ideas"}

I add the following to the ideas_controller.rb:

    def upvote
      @idea = Idea.find (params[:id])
      @idea.upvotes = @idea.upvotes + 1
      @idea.save
      redirect_to(ideas_url)
    end

In the next lines, I'll say upvote but that works the same for downvote.

First, create a member route upvote, then you can link from your show view to the new action using upvote_idea_path.

Second, create an action upvote in the controller which increases the vote count by 1 and you're done. That's all.

You can achieve this functionality with the thumbs_up gem. It is also Rails 3 compatible.