test_form_screen.rb

class TestFormScreen < PM::FormScreen

  title "PM::XLFormScreen"

  form_options required: :asterisks, 

                     # by default, button "title" is NSLocalizedString("Save")
                     on_save: :'save_form:', 

                     # or 
                     on_cancel: { action: :cancel_form, item: :cancel, title: "Cancel" }

  def form_data
    [
        {
            title:  'Account information',
            footer: 'Some help text',
            cells:  [
                        {
                            title:       'Email',
                            name:        :email,
                            type:        :email,
                            placeholder: 'Enter your email',
                            required:    true
                        },
                        {
                            title: 'Name',
                            name:  :name,
                            type:  :text
                        },
                        {
                            title: 'Yes ?',
                            name:  'check',
                            type:  :switch
                        },
                        {
                            title:   'Options',
                            name:    'options',
                            type:    :selector_push,
                            options: {
                                "value_1" => "Value 1",
                                "value_2" => "Value 2",
                                "value_3" => "Value 3",
                                "value_4" => "Value 4",
                            },
                            value:   "value_1",
                            on_change: lambda {|old_value, new_value|
                              puts "#{old_value} has been changed to #{new_value}"
                            }
                        }
                    ]
        },
        {
            cells: [
                       {
                           title:      'A slider',
                           name:       :slider,
                           type:       :slider,
                           properties: {
                               max:  100,
                               min:  2,
                               step: 4
                           }
                       },
                       {
                           title: 'A date',
                           name: :date,
                           type: :date_inline
                       },
                       {
                           title: 'Another date',
                           name: :other_date,
                           type: :date_inline,
                           properties: {
                               min: NSDate.new
                           }
                       },
                       {
                           title: 'An image',
                           name: :picture,
                           type: :image
                       }
                   ]
        },
        {
            title:   'Multi-value',
            name:    'multi',
            options: [:insert, :delete, :reorder],
            cells:   [
                         {
                             title: 'Some text',
                             name:  :some_text,
                             type:  :text
                         }
                     ]
        }
    ]
  end

  def save_form(values)
    mp on_save: values
  end

  def cancel_form
    mp 'cancel_form has been called'
  end

end

Just a "thinking out loud" idea:

class TestFormScreen < PM::FormScreen

  title "PM::XLFormScreen"

  form_options asterisk: true, on_save: :'save_form:', on_cancel: :cancel_form

  def form_data
    # ...

so, it will be

class TestFormScreen < PM::FormScreen

  title "PM::XLFormScreen"

  form_options required: :asterisks, 

                     # by default, button "title" is NSLocalizedString("Save")
                     on_save: :'save_form:', 

                     # or 
                     on_cancel: { action: :cancel_form, item: :cancel, title: "Cancel" }