title: Edit View Fields in Rails Admin
body: <p>I am using 'Rails Admin' in my application. In my initializer I have the following in 'rails_admin.rb': </p>
  
  <pre><code>config.model "Player" do 
    edit do
      :name
      :team
      :shooting_percentage
    end
  end
  </code></pre>
  
  <p>That gives me the following fields on the edit view in Rails Admin: name, team, and shooting percentage. </p>
  
  <p>I would like to add two fields to the edit form in Rails Admin for Player but I don't want to make them as attributes on that model (or any model for that matter). I want to add shots, and goals as just form fields.</p>
  
  <p>The reason I want to add those two form fields is so that I can use them to calculate the 'shooting_percentage' attribute value on Player. </p>
  
  <p>Is there a way in Rails Admin to have fields on a form that are not fields on the model? Furthermore, if that is possible is there a way to use the values entered into those form fields to calculate a value for an actual model field (shooting percentage)?</p>