```ruby
module JohnHancock
  module Rails
    module FormBuilder
      include ActionView::Helpers::TagHelper

      def signature_field(attribute)
        tags = []
        tags << content_tag(:canvas, nil, class: 'Signature-visable Signature-pad', id: 'JohnHancock-canvas')
        tags << hidden_field(attribute.to_sym, id: 'JohnHancock-hidden')
        tags.join(',').html_safe
      end
    end
  end
end

JohnHancock::FormBuilder = JohnHancock::Rails::FormBuilder
```

Add separate methods for canvas and hidden field
user
```ruby
module JohnHancock
  module Rails
    module FormBuilder
      include ActionView::Helpers::TagHelper

      def signature_canvas
        content_tag(:canvas, nil, id: 'JohnHancock-canvas')
      end

      def hidden_signature_field(attribute)
        hidden_field(attribute.to_sym, id: 'JohnHancock-hidden')
      end

      def signature_field(attribute)
        tags = []
        tags << signature_canvas
        tags << hidden_signature_field(attribute)
        tags.join(' ').html_safe
      end

    end
  end
end

JohnHancock::FormBuilder = JohnHancock::Rails::FormBuilder
```
assistant