title: Rails simple_form checkboxes for serialized Array field
body: <p>I am using SimpleForm to build my form.</p>
  
  <p>I have say the following model:</p>
  
  <pre><code>class ScheduledContent &lt; ActiveRecord::Base
      belongs_to :parent
      attr_accessible :lots, :of, :other, :fields
      serialize :schedule, Array
  end
  </code></pre>
  
  <p>I want to construct a form, where among many other fields and associations (this model is actually part of a has_many association already - so quite a complex form) a user is presented with a variable number of days (eg Day 1, Day 2, Day 3, etc) - and each day can be checked or unchecked. So if a user checks Day 1, and Day 5 say - I want to store [1, 5] in the schedule field. Before the form - I can construct a simple array of possible days to choose from, including obviously the days already chosen.</p>
  
  <p>What is the best way to represent this form using SimpleForm's form helpers? If it is not possible to do so - I could use Rails' form helpers too to make it work, but my preference is SimpleForm as the rest of the form is already constructed using SimpleForm.</p>