[How to] Set the Activity's owner to current_user by default

You can set up a default value for :owner by doing this:

1. Include PublicActivity::StoreController in your ApplicationController like this:

class ApplicationController < ActionController::Base
  include PublicActivity::StoreController 
end

2. Use Proc in :owner attribute for tracked class method in your desired model. For example:

class Article < ActiveRecord::Base
  tracked owner: Proc.new{ |controller, model| controller.current_user }
end

Note: current_user applies to Devise, if you are using a different authentication gem or your own code, change the current_user to a method you use.