uninitialized constant Formtastic::SemanticFormBuilder (NameError)

[pslaski]

SemanticFormBuilder is now deprecated

[pehrlich]

Here's some working code:

class DatepickerInput < Formtastic::Inputs::StringInput

  def input_html_options
    format = Time::DATE_FORMATS[:american] || "%m/%d/%Y"
    super.merge(:"data-datepicker" => true, :value => object.send(method).try(:strftime, format))
  end

end

see: https://github.com/justinfrench/formtastic#creating-new-inputs-based-on-existing-ones